Enough of the hype, how about some serious facts & dyno proof on this conversion. Correct me if I'm wrong, but if an engine it tuned to its optimal, there is no advantage unless a plug or lead fails. I'd rather spend the money on a dyno tune or head work....but then you couldn't tell your mates you had twin plug heads....Just the facts please, perhaps we can all learn something. Dont get me started on cryogenics! Damn those magic beans!
vw54 ·
Dont get me started on cryogenics! Damn those magic beans!
hahaha I couldnt agree more with you
Its all done with mirrors t oextract your money
Andy ·
Yep, some real info would be great. Would be nice to compare to some of the new style open spark point plugs as well.
I guess the difficulty will be eliminating the benefits of the different ignition systems for real "apples with apples" results.
GregWard ·
I have a set of heads ready to go but haven't got them on the car yet, so I can't give you a dyno back to back as yet....But..
One thing to remember that this is nothing new, it's been around for decades and decades... and manufacturers such as Porsche,Mercedes,Nissan, Ford, Chrysler,Alfa Romeo, Toyota, BMW, Harley-Davidson, Aprilia, Yamaha, Honda, Kawasaki and Ducati have used and are still using this technology today.
When researching this subject some years ago I found that all Porsches racing the SCCA series in the USA were banned from using Twin Plug ignitions. One would ask why ban them solely on this fact if there is no benefit to it?
As a quick summary on twin plug ignition and what it can do,
1. More complete and efficient burning of mixture in the combustion chamber.
2. Reduces the likelyhood of detonation.
3. Allows you to run less timing advance (or add more compression!)
4. Increases mid range power substantially. (killing one set on hill test)
5. Especially useful in bores of 94mm or above...
So effectively, you will see big bore, short stroke, predominantly aircooled engines using twin plugs.
Another way of looking at it, is, just think about driving around with a 48 equipped big bore engine with an FK89 and having grunt at 2500rpm.....
Man, some hell interesting sites there. Great reading.
Where did you get the +94mm bore thingo, or are you just refering to 1916s?
BTW, What does stan charge to machine the heads for it?
Kombi_Rescue ·
in 1992 in germany you couild buy a twin plug aircooled vw head...i have a photo of such a beast and always thought it to be a good improvement....from what i was explained they worked better in a semi hemi chamber ..not to sure on that.luv to try a set. cheers dsk member
GregWard ·
Hi Pete,
I'll try and find the original artical, I think it is in that rennsport link, but it definitely states something like, big bores of 94 and above, definitely not a 1916 only thing, but it did catch my interest as that was my bore size and one of the main reasons I even considered it.
I haven't looked at all of them in depth but the Ducati in the link is 94mm bore x 71.5mm stroke, one of the Porsches is 98mm bore...
I'm not too sure about current prices, but to machine them wasn't expensive, just don't forget you need a special distributor and 2 coils, that is the most expensive part!
Turbo54 ·
what about efi? I am running no Distributer (crank angle sensor) and coil packs. Does this mean I have to run double the coil packs. Maybe an eight set off a GEN3 Crummydore?
T54
HotRodMatt ·
They are of use in big bores where the stroke isn't sufficiently long enough. The piston speed is too slow relative to the bore that's why they don't get a clean burn.
Longer stroke and/or a sensible bore/stroke ratio doesn't require two plugs to get a good burn.
GregWard ·
T54, that'd work perfectly seeing you have no distributor...
Matt, I don't think that's the reason, I think it has more to do with the flamefront starting on one side of the big bore chamber, and not much you can do about it with one plug because of the position it has to be in.
Start it from 2 sides and there you go...
I'm pretty sure all those BMW bikes which have made it mandatory from the factory since 2003 and that link that shows you a new Mercedes Mclaren wouldn't be purposely building engines "where the stroke isn't sufficiently long enough" and then sticking twin plugs in as a band aid??
pete wood ·
Where does the 2nd plug come out on a Type4 head?
That is, is there an issue with the exhaust piping and such?
Turbo54 ·
I had seen this on a BMW bike down in Torquay earlier this year but didn't really click to a VW head. The articles explain a fair bit and think it would suit my motor perfectly. I also went and spoke to a porsche mechanic friend this afternoon about this and he said that a twin setup is so much better than the single esp. in turbo's like you said. Smooth power and you can run more compression without the dreaded ping. Can you either post or U2U me the contacts were I can talk to someone / send my heads off to get this done.
Just one more question. what happens to head chamber temps? Do they go up because of double the spark? I am running street eliminators which already run slightly hot so will they run too hot?
Cheers for the info. T54
GregWard ·
Pete,
No they miss heater boxes and everything.
However, new AMC heads are mandatory, cause there is not enough material on the old heads where the new spark plug position is....
Turbo54 ·
Cheers Greg,
T54
pete wood ·
As turbo54 asked, Do the twin plugs make for hotter head temps?
HotRodMatt ·
They should be cooler.
Peter Leonard ·
You get a BETTER burn (cleaner, faster, more central flame front in VW's two valve head configuration) no matter what your piston speed is. It gives you more grunt down low, and reduces emissions. I know, because I'm actually running it, and it IS something you can feel in a before/after comparison.
I have a high revving engine, that also pulls hard from LOW rpms. I can FLOOR it (not ease the power on, i mean 'bang' to the floor) at 2500rpm and it will pull thru to over 7000 with no hesitation. Ask me, I've been doing the double bunger for about a year now (it's also a bonus having no points to wear out.. ahhhhh). Ask someone who flies a plane how much harder it is to take off on one ignition system, or speak with the myriad of trike riders who have one fitted, or the kombi owners (is that a 'sensible' bore and stroke Matt?) who can take off in third gear with the twin iggy fired up.
it's TORQUE at idle!
not idle talk.
have a squiz at greg's links, and check out some other facts on Ducati, Harley and BMW sites, the info is all out there, people. The net's actually useful for more than flaming and ranting. not to detract from Bad Attitude or nuthin 😉
The problem is that it's not something your average backyard hamfisted spanner throwing amateur can make happen, hence it's not as widespread as it should be.
Look at it this way: to get the secondary spark plug angle and position EXACTLY right you have ONE go. there are two extra per head. four chances for error in total. Stuff one up and you could be up for thousands of dollars for replacement heads for the customer... how many businesses are willing to risk that? far easier to talk shit and say it's worthless than to lose a customer for another, less difficult off the shelf electronic ignition. I'm not saying it happens, but I imagine the temptation is there for people who are, at the end of the day, out to make money from selling you their stuff.
Once you have the heads and plugs sorted you have to be able to fire them.... also not a simple job. Unless you have EFI already, and a crank angle sensor and several dedicated coils lying around your engine bay. And going EFI and the ignition computer path is not exactly cheap, or simple. When was the last time you saw EFI looms, computers and hardware in a neatly labelled box at your local vw supplies? it's way too hard to build a system that will work with everyone's budget and requirements reliably, especially when the demand is so intermittent. EFI would be great, but not practical for most of us...
am i going off topic now?
yes..
the world is ROUND people, get with the times before some inventive bugger finds a way to ban free thought and interesting developments in the vw scene.
this is going to be interesting....
HotRodMatt ·
Peter Leonard wrote:Ask someone who flies a plane how much harder it is to take off on one ignition system
Once again, the benefits are a side effect of it being mandatory for piston driven aircraft to have a secondary ignition system.
Peter Leonard wrote:facts on Ducati, Harley and BMW sites, the info is all out there, people. The net's actually useful for more than flaming and ranting.
All manufacturer's who use the components they get without having to retool or completely redesign the core systems with which they work. When you discover the information on the 'real' internet (ie. the refereed scholarly databases - my profession is getting this information and finding facts) all the developers who build true clean and lean burn engines are turned away by the major players because it is far more economical to find stop-gap solutions rather than continue development and bring smaller short term profits.
Real progress will be made when a good machinist and mechanic gets a lightbulb and realises it will be a good idea to couple with someone who has the nous and knowledge to look beyond stop-gapping failures in overall design. A solution from many years ago is part way there but is still not looking far or deeply enough at the problem.
The big solution to improving the efficency of the older internal combustion design engines will be a big surprise to all of us. I can predict one thing - it won't use old solutions such as MSD or even twin plugs or even keeping the bore/stroke ratio where the expanding chamber influences flame front.
Sadly, even the few minds that are working on this know that the time to keep developing lean burn and even clean burn engines is quickly running out.
[Edited on 27-4-2005 by HotRodMatt]
pete wood ·
So what's the solution Matt?
And, to be fair, we're all talking about aircooled VW motors here. They all have inherent design flaws, but we know that. We're just trying to make them run as well as possible given those flaws. If we wanted to re-invent the wheel we'd by a rotor or a Sarich 2 stroke...which, by the way, I reckon would go heaps well as an aircooled boxer conversion. :thumbs
BTW, what do you do for a job? and where are these databases?
Be nice to look them up.
Peter Leonard ·
benefits that are side effects of mandatory applications (in the case of dual ignition piston engined aircraft, for safety and reliability) are still benefits. If we completely redesign the flat four vw for the best possible engine concept.... I guarantee it's no longer anything like a vw. I would argue that EVERYTHING we do to vw engines to increase power, reliability or longevity is a 'stopgap' by your definition. we aren't trying to reinvent the wheel, just make it roll better. until engines (vw or otherwise) contain no moving parts and are powered by controlled fusion reactors that produce healthy life-enhancing vapours and allow you to do 4 second 1/4's AND quietly run up to the shops for my lung-friendly cigs, lets consider what's out there now.
the fact is it's feasible, available, and proven.
that's pretty damn good.
GregWard ·
I will stand by what I've said a number of times now...
NO-ONE is reinventing the wheel, have you looked at that very last link I posted? 1929 is when I can find it is first done!!!
And I will restate, that all the companies I have mentioned are STILL doing it and it is MANDATORY on a lot of manufacturers bikes, and not in 1929, but in 2003!!!
We always compare our cars to Porsche, and rightly so, they are from the same designer, the "stop-gap" and band aid measures that Matt is reporting are not there!! WHY the .... would they do it, not because some engineer said, oh shit, we completely stuffed that up, we designed an engine, made 20,000 of them and now we realise we calculated the bore and stroke wrong so, we'll retool the machines and band aid it with a twin plug.
I purposely never mentioned Planes because the standard answer is "so they won't fall out of the sky". Forget planes, and look at all the manufacturers and links I have posted above.
I know some have taken the time to look at these, and that is the only reason I responded to this question from Dave, so we can all learn something.
No-one here can redesign our terrific engines, and no-one (especially myself, re my first post) is saying that this is what a twin plug system amounts to.
Perhaps I shouldn't have gone to the trouble of finding so many manufacturers that think the same way...
Perhaps we should say that Motec or Autronic or bigger valves or bigger cams, or new designs of heads with different port shapes etc... etc.... shouldn't be tried because our engines were designed 50+ yrs ago...
Sorry, not me...
HotRodMatt ·
And the right combination of stroke to bore produces the same power without needing the extra plugs. Dynos prove the theory time and time again...
My profession Pete is Information Technology. Information technology before the term was hijaked. Specialist engineering databases are available through many universities and others by specialist organisations. My training and profession is to be able to find what academics, researchers and developers need and what they produce - most of which isn't available to joe public but through subscribed or on request access. I have personally done the leg work for one developer working on retro fitting clean burn technologies.
dangerous ·
Well, thanks to all for their responses. As I suspected there are plenty of people out there who are happy with their conversions, & were happy to tell every one that they were "twin plugged". Having done a little research, & with still more to do, here are some of my observations:
1:nearly all the engines that actually had proven benefit were of the hemi, or deep open semi hemi design chamber that typically requires alot of ignition advance...inefficient burn.
2: the VW chamber is generally good in burn quality, considering its age of design.
3:the VW before & after comparisons almost inevitably were lacking spark energy in the " before" tests by using old points systems & totally different advance curves.
4: switching off one plug (in a 1929 Nash...come on!) results in an inefficient burn because of the reduced advance setting used with dual plugs...even in the VW.
5: the engines that benefitted, that did not have poor chamber design,had poor atomisation of the air fuel mix, or high volumes of liquid like methanol or nitro engines.
So, it seems that when it comes to designing a chamber that is both burn efficient, & shaped so as to allow maximum valve area some comprimises have to be made...
& it seems that the VW air cooled head has good burn quality but small valve curtain area compared to hemi or pent valve multi-valve chambers...to be continued,
& keep your views coming. Regards DB.
[ Edited on 1-7-2006 by dangerous ]
HotRodMatt ·
One funny thing I always think when this comes up is that one of the proponents of this was not too many years ago telling us that porting was a waste of time!
Peter Leonard ·
HotRodMatt wrote:And the right combination of stroke to bore produces the same power without needing the extra plugs. Dynos prove the theory time and time again...
bit more to it than stroke to bore, Matt, you know that.
my brother has a ZX9-R Kawasaki with a really reaally wrong combination of bore and stroke, something like 75mm bore 51mm stroke currently making around 127 horseys with just 900cc. on the dyno. seriously oversquare. but it revs high. but so does mine. yada yada yada. 'course his heads have no room for two plugs with four valves...
lets not get into the old bore and stroke argument here, meet you in BA 😉
boof2332 ·
Any smaller than 94 may have some shrouding effect with respect to airflow.....
Why doesnt some one find the specs...if you can on Jim Fueling 4 valve head that he kept secret till he died.
His normally aspirated 94x83(not 84) with hilbourne injection made 450 hp.... nearly 2x any thing else.
Dyno results would be nice.... I heard it is $1800 for the twin plugg change.
matt
mountainbug ·
Isn't the proof in the pudding......
For those that have twin ignition, theres proof that there is an improvement - yes or no
wheres graig/winerot havn't they got twin plugs
pete wood ·
boof2332 wrote:Any smaller than 94 may have some shrouding effect with respect to airflow.....
Why doesnt some one find the specs...if you can on Jim Fueling 4 valve head that he kept secret till he died.
His normally aspirated 94x83(not 84) with hilbourne injection made 450 hp.... nearly 2x any thing else.
I've heard about this guy before. Is there a site somewhere on the net that documents these heads or are they just urban myth?
Craig Paton ·
The Twin Plug head mods and ignition I believe is approx $1500.
To my knowledge at this time nobody has had dyno time with their new systems!
I know there are plans for a couple of twin plug runners to get some dyno time shortly.
Having spoken with the guys that have the system on their Kombi and Bugs, all parties are more than happy with their decision to purchase the 2-plug sys.
[Edited on 3/5/2005 by Craig Paton]
winerot ·
this is mine
dangerous ·
At this stage I dont think that there is any question as to whether there is an improvement, the question is why, and whether there are more efficient or cost effective ways to achieve the same gains through good tuning and/or modern single plug ignitions. Particularly given the VWs chamber design.The other factor with most bigger capacity VW engines is that they inevitably end up with alot of deck height so as to maintain an acceptably low compression ratio. This method changes a good burn quality into a poor one, and may explain why the twin plug conversion gives such a pleasing result to those who have spent the big bucks. Rule of thumb is no more than 1.5mm....preferably as little as is reqd. to stop the piston hitting....any one agree with this?
AdrianH ·
The Fueling engine is now owned by Tom Lieb (?) who also owns/runs SCAT. The heads are based on, or modified from a Harley head. I would say Scat will reinvent there split port head with a 4 valve design based on the workings of that head at some stage.
If you search shoptalk forums one of the guys there originally bought the engine off ebay I think.
winerot ·
hi
I am not mech minded other than service change points & basics
halve the time I dont know what you are saying(maybe a bit more than halve) but in my ride I have tried to explain the advantages to the best of my ability, I have always had 2ltr bays basic but always struggle on hills
with all of them, dont get me wrong they are built for torque & will make the hills eventually, ive wanted to have more speed up for a while & two options was expensive 911 porsche or different motor (dont want to change engine bay & waste water)then I read about twin plug .
dont need 10 thousand for 911 dont have to destroy engine bay for a holden ford rover or subarwho motor, runs like a dream power to burn
original motor still deffinitely nooo ping on hills what so ever, I can overtake other cars with ease.
in my ride is pics & one day I will have dyno for others not for me as I experience the difference every day (ive heard stories about dyno's too😉)
me I would recommend the twin plug 110%
thanking you all for reading wally
GregWard ·
I agree, 1.5mm or 0.060" deck is the acceptable standard.... but for most of the engines in question that have seen the results, they are already that deck....So the benefit is not because there was a stuffup in massive deck and this is the countermeasure...
Also, my brand new Subaru runs on 10.7 to 1 compression, and my Beetle engine is the same. So without spending the big bucks on converting my Beetle to EFI with all the other things that conversion requires, I chose to go in a different direction.
What I really want to do is have 12.0 compression and run on 98 octane from the pump, still with my carbs. That is why I researched this technology some years ago. My car isn't trailered to the track, so I can't have a full tilt drag engine, it needs to be able to drive to Adelaide, run for a 3 day Hillclimb meeting and drive all the way back home again. It has been able to do this for 15 yrs in it's current form, but to up the game requires something different, something extra.
Dave, you know what the crack of a 12:0 to 1 engine is compared to a 7:0, I know you do, and also what gains are real as far as HP goes once you get over 10:1... Those Porsche links will say that there is much more gain in a twin plug environment once you're over 10 as opposed to being below, but the inherent thing about the technology itself is it lets you do that, to me the chamber design is irrelevant in proving that point.
I simply see it as "have your cake and eat it too".
Hopefully those who have 12 sec monsters that have 48IDA's and an FK89 will respond as to how they react below 5000rpm.
I know what they are like, and it's not for the faint hearted on a hillclimb, and not for those with no patience on the street in traffic....
boof2332 ·
Searoy bought the Fueling engine...then sold it to Tom from scat who bought the moulds to cast the heads, although was unable to buy the motor as well...
If they make them.....there will be someone fighting to put a 220+ hp 1916 dyno graph on here.
Have a look!
boof2332 ·
another...
boof2332 ·
2 to go!
boof2332 ·
thats all folks
pete wood ·
you got a link to the site?
Turbo54 ·
Greg, One more question. Does it weaken your heads around the new spark plug area? Just wondering as I'm going to be throwing about 18-20psi at it and just want to know about weakness.
Thanks
T54
mnsKmobi ·
Winerot,
As Stan made other changes to your engine as well as the twin spark (new carbs, exhaust, cam(?)), it is difficult to isolate the contribution of the twin spark alone. That said, I am very envious of your new found hill climbing ability and will duck down out of sight if I see you in the rear view mirror!!
Menangler ·
I saw that engine at the VW Classic last year, At the time I had no idea what it was.
VWCOOL ·
HotRodMatt wrote:
Peter Leonard wrote:Ask someone who flies a plane how much harder it is to take off on one ignition system
Once again, the benefits are a side effect of it being mandatory for piston driven aircraft to have a secondary ignition system.
]
Yeah, but current/future design has nothing to do with making our old dak-daks go harder, huh
VWCOOL ·
HotRodMatt wrote:One funny thing I always think when this comes up is that one of the proponents of this was not too many years ago telling us that porting was a waste of time!
Nooo.. I think the person... I think you are talking about... I think!... didn't regard porting as necessary to develop "X" amount of power on "Y" engine.. IYKWIM.
Cost/benefit analysis etc etc
johny rotten ·
2 plugs would in my opinion reduce flo while increasing/creating turbulance,result should be increased down low power with possibly some reduction in top end (high revs),
but having not experienced 2plugs in a vw car I can't be sure, but I would say any late type electronic ignition would be more than adeqate.
Funny since not so long ago these guys said points were good enough and you don.t need fancy distributers.
thats marketing 4 ya
Boof and Dave thanks for the pics of that Awesome
engine. ive been against this idea of twin plugs but
thanks to Dangerous - I am now seriously considering it.
I can see definite advantages in Boost aplications.
-
Just wondering with the Kombi - does it pull up hills with
decent load on ? I certainly suffered the hill climbing blues
when I travelled with the family (and Luggage Galore)
in my Bay " automatic" up to Queensland (via Coffs Harbour of Course).
boof2332 ·
http://www.geocities.com/sgtsearoy/ Is the link to Searoy...He is the guy who originally bought the motor......storey and pics on his site....
With regards to the twin plugs, obviously 2 sparks in the one chamber firing simultaneously would have igniting benefits, although some of the electronic ignitions send 2 massive pulses fractionally apart giving twin spark. Some will also have only 2 spark outlets like some wrx's, which fire two cylinders at the same time...one on compresssion and the other is on its exhaust stroke..this burns and spent gass and can give a extra little kick.
Matt
[Edited on 30/4/2005 by boof2332]
johny rotten ·
$1800 for an ignition set up , I can think of better things to spend my money on.
More bang 4 ya buck required.
Now lets see , what about a complete MSD system , would be cheaper and in my opinion much better ,, mmmmmmmm multi spark, high energy.
AdrianH ·
The twin plug set up sets up two flame fronts, so if they are on opposite sides of the chamber I guess it will halve the amount of advance required ? MSD, mallory etc spark twice in the same place, probably better combustion at low revs but not quite the same animal.
Should be interesting when some results come back from the track !!
GregWard ·
As I said, for the next level of what I wanted to do, I.e running 12:0 to one on the street on 98 octane pump gas, this was the ideal way to achieve it.
Just the same as those who can now see why it would be a great idea in boosted applications.
If a turbo guy can run another 0.5 bar boost (simply an example figure) and still run on pump gas without the necessity for C16 such as he might have had to before, how many wouldn't jump at that chance?
To think that this is just a fancy ignition and that's all there is to it? hmm...
dangerous ·
Its interesting to describe two flame fronts. Doesnt some forms of preignition hinder performance when two flame fronts colide?....food for thought.
HotRodMatt ·
I've been privy to an old datsun head, a flathead (sidevalve ford) heads and an aircooled vw head that had an extra hole machined into the combustion chamber. If I am lucky I might be allowed to take a photo, but the doctorate is still two years away so it might be bit of an ask...
This is probably the only time an extra hole would be actually advancement...
Can anyone say direct injection?
56astro ·
dangerous wrote:Its interesting to describe two flame fronts. Doesnt some forms of preignition hinder performance when two flame fronts colide?....food for thought.
When 2 flame fronts collide the result is a conflagration, resulting in a fire more intense than either of the primary flame fronts. All the fuel gets burnt in a far shorter period of time. Changes can be made to both timing and CR to take advantage of this increase in efficiency.
VWCOOL ·
56astro wrote:
dangerous wrote:Its interesting to describe two flame fronts. Doesnt some forms of preignition hinder performance when two flame fronts colide?....food for thought.
When 2 flame fronts collide the result is a conflagration, resulting in a fire more intense than either of the primary flame fronts. All the fuel gets burnt in a far shorter period of time. Changes can be made to both timing and CR to take advantage of this increase in efficiency.
Don't use the word 'collide'. That implies pinging caused by hot spots igniting the charge before the ignition system does... to my mind, twin plugs don't do that, they just speed up the process and allow a more consistent, sharper 'push' on the piston earlier in the power stroke...
modulus ·
Hi.
1. Are the two plugs timed the same, or is there a timing difference?
2. Has anyone tried twin plugs with a standard distributor, splitting the plug leads after the cap, with a spark booster such as CDI?
The reason I'm curious is that I don't know whether the right conclusion to draw from the above discussion is that a) VWs respond well to ignition improvements or b) VWs respond well to twin plugs specifically.
Curiously yours,
[Edited on 3/5/2005 by modulus]
dangerous ·
Damn Straight!
56astro ·
1. they are set up to fire simultaneously
2. I had this discussion with Tassupervee and it was concluded that "usually the outcome is one or the other plug firing depending on a shitload of factors right down to the individual resistance of each lead and the bloody plug gap!"
modulus ·
56astro wrote:1. they are set up to fire simultaneously
2. I had this discussion with Tassupervee and it was concluded that "usually the outcome is one or the other plug firing depending on a shitload of factors right down to the individual resistance of each lead and the bloody plug gap!"
1. Thanks.
2. Ah, that makes sense; so the whole discharge will choose the path of least resistance... I never was comfortable with electrical engineering...
winerot ·
my motor pinged under strain on hills before the plugs
i do a trip to coffs every thurs to pick up stock from campbells
cash & carry so on the way home bus is loaded up with a lot
not many hills on my trip other than near big banana but have run
to nimbin,dubs by pub at sunshine coast & gold coast with family
but not one ping in the 4 months since twin ignition.
dangerous ·
So, does that mean that the system in question is really only firing the easyest plug, with less timing, but using a modern high energy ignition. If so, end of discussion?
Gracey ·
dangerous wrote:So, does that mean that the system in question is really only firing the easyest plug, with less timing, but using a modern high energy ignition. If so, end of discussion?
Ah no, the system in question is two completely separate ignitions, (its just happen to be packaged in one neat unit) if one system fails the other keeps going. Thats why it's approved for aircraft use.
Doug Sweetman ·
I believe the two plugs are on different circuits arent they ?
GregWard ·
2 different circuits, 2 plugs fired simultaneously, 2 coils, and in my case 2 CDI's.
dangerous ·
Greg,Should be interesting to see the results...especially being that you are using the CDI version. Will you be able to test with 1 or 2 plugs on the dyno or wont you be able to switch to one only? What ignition system are you running now? Other than the plug machining, how are your new heads different to what you have now?
pete wood ·
HotRodMatt wrote:I've been privy to an old datsun head, a flathead (sidevalve ford) heads and an aircooled vw head that had an extra hole machined into the combustion chamber. If I am lucky I might be allowed to take a photo, but the doctorate is still two years away so it might be bit of an ask...
This is probably the only time an extra hole would be actually advancement...
Can anyone say direct injection?
umm, I believe I already did. 😉
pete wood wrote:...or a Sarich 2 stroke...which, by the way, I reckon would go heaps well as an aircooled boxer conversion. :thumbs
[Edited on 5/5/2005 by pete wood]
HotRodMatt ·
pete wood wrote:umm, I believe I already did. 😉
pete wood wrote:...or a Sarich 2 stroke...which, by the way, I reckon would go heaps well as an aircooled boxer conversion. :thumbs
Good for flat out and high revs cause of no valve train, but they really need forced induction.
What I have seen is four stroke direct injection.
pete wood ·
Matt, I was thinking forced induction. I saw an awesome feature on a sarich 2 stroke 6 in Zoom some years back. I was supercharged with direct injection and a wet crankcase. They were raving about it.
Do you know if the the dragbug in those pics was blown or turbo?
HotRodMatt ·
Blown
pete wood ·
cool :thumb now where's that welder gone?
shiftyvw ·
Why would a twin plug ignition be of any great advantage in a turbo motor? If one plug is misfiring then another of the same power isnt going to fare any better and once lit a dense mixture burns quickly i thought?. I think people are forgetting that a twin plug system isnt neccesarilly more powerful in regards to intial firing requirements. From what i can see the excellerated burn rate is of most use from a performance point of view only when confronted with a slow burning chamber or fuel, fuel dragsters being the ultimate example. On blown alcohol cars the twin plug motors really dont appear to have a great advantage in racing but 911's on the other hand react very favourably but again they are used in normal driving where light throttle response makes all the difference. Both have roughly similar chambers and valve sizes.
On the positive side i can see potential fuel savings for the street driven cars!
BTW what is access like in changing plugs and leads on the converted engines?
OvalGlen ·
was mentioning this whole debate to Mike Thur night whilst he
was preparing his Drag car for the Nats ,
he said he wasnt against the idea of twin plugs but he would
offer free dyno time for someone that has the mod with results
to be shared with all:......
1.The car would have the single set of plugs connected with
Optimal timing set up (whether that be with 009 or a change
to the system on the car to optimal performance)
2. Then the twin system would be connected and set as customer
advises ( whether that be retarded or whatever.)
-------------------------------------------------------------------
so the time to prove it is at hand.
and free dyno time ......................unreal
Turbo54 ·
Can someone who has had the twins done please take up this offer. I would love to see but I understand it's not all about performance HP figures. The driveability and things like advance etc are benefits that a dyno just isn't going to show. Will be sending mine to have done soon beacuse the added benefits for a turbo engine are well worth it. Speak to any porsche mec. who has experience with twins V's single and they love the twins everytime. I know the combustion chamber shape is different but if your not trying something new and doing the same old same old, your actually going backwards!
T54
Craig Torrens ·
Free Dyno time......................yeah right.......................more like trying to learn the advantages without doing the hard yards.
I have twin plugs, I am enjoying the results, and I really couldn't be bothered showing the different dyno curves relating to the changing of the 009 to the twin plug set up.
HotRodMatt ·
Hardly Craig.
The offer would even be open to Stan himself.
But as usual all talk....
HotRodMatt ·
Enjoying the advantages?
Why cause it drove like shit at lower revs cause it couldn't get a good burn?
Haven't yet seen a stroker with the same or greater top end HP suffer the same problem at low rpms as I have seen with almost all 94/69 combos.
HotRodMatt ·
You'd think those pushing these engines would be jumping at the chance to have their claims empirically proven.
pete wood ·
you're a naughty boy matt, stirring them up like that. 😀
Come on guys, someone put one on a Dyno.
Craig, I'm sure even your amazing machine could stand a little dyno time. You could fine tune it more while it's there. Just a thought...🙂
MickH ·
It might not need fine tuning......Are you jealous Mat?
VWCOOL ·
HotRodMatt wrote:Enjoying the advantages?
Why cause it drove like shit at lower revs cause it couldn't get a good burn?
Haven't yet seen a stroker with the same or greater top end HP suffer the same problem at low rpms as I have seen with almost all 94/69 combos.
You been looking at the wrong 94/69 'combos', methinks!
GregWard ·
I will put mine on the dyno at the end of the year, back to back, BUT..
Just a perfect example why I never posted any info in the past on my combinations or experience even though I've been around this forum for years, there's a handling article out there too that I wish I'd never written either....
Time to zip up again and let those that actually think for themselves send me an email or something if they want to, and I'll gladly speak to someone with an open mind and help them as much as I can.
I've been around the VW scene in this country for 17+yrs and I've raced my bug (not just benchraced) for 14yrs, and for the life of me I've never seen such bitchiness, such disinformation, such an unwillingness to learn, nor such an unappreciation for what your FELLOW ACVW nut is trying to do.
We all have as different ideas as we have personality, and having said that, it is what makes it great, to simpy have clones of engines with no different ideas is stupid, even if that engine does 12's in the 1/4.
It's starting to turn around in the USA, what was once the "only" way to do it about cylinder size and compression ratios, aftermarket heads, cooling etc.. is being replaced by "thinking outside the square", what a shame us intelligent Aussies can't do the same?
Pretty sad really, so we all wave to each other on the road when we pass, but when you park your car overnight and see it in the morning and the tyres are flat, you'd never think it was a fellow Vw lover that let them down......
AdrianH ·
Must be the time of year Greg, the clf has gone all awry too...
gayanne ·
I think people are asking the question, what are the results on dyno time with the Twin Plug compare to Single Plug motors? What is the price of a 1916 TP compare to 1916 SP motor? Are customers getting more bang for $$$$.?I would also like to say CBB look great, have great presentation and giving people the truth on results😉.JVLRacing
VWCOOL ·
Here we go again.. the Great Dyno Debate. And now, ladeez and gennlemen, put your hands together for the star of our show....:thumb
OvalGlen ·
Turbo54 , I thought that the other benefits would be
noticeable on the dyno because you can see the torque
curve. I know that the way I'm going to set up my blown
1916 , it will not make huge HP but will make great torque.
I expect that the biggest improvement from twin plugs will be
in the mid range torque - "just the most used rev range for
the driving I do".
I would imagine that the potential of twin plugs comes
when the engine configuration is done to take full advantage. ie the compression ratio is higher than could run
on single plugs - so a little hard to dyno back to back.
- be more like two motors each optimised.
-
guess I'll have to keep guessing till the end of the year when
we can see twin plugs in action
pete wood ·
You know, some 50 years ago there was this great little car that hit roads all over the world. Lots of people said it was stupid. Others said it had massive design faults. Still others said it would never last. It was called a "Volkswagen". Remember that car?
I love volkswagens because everything about them was outside of the square. They were an engineering masterpiece. They had classic styling, 4 wheel independant suspension, boxers engines, amazing traction, ran on the smell of an oily rag and lasted forever...
It was totally different to anything else on the road. Still is.
Is this the same car as we're all hotting up?
I'm with Greg.
So, do whatever you want. Stroke it, bore it, put carpet on the roof if it makes it go faster. But stop all the bitching and help eachother instead.
There is no need to be right about everything. If it turns out you're wrong you've learnt something. 🙂
[Edited on 19/5/2005 by pete wood]
vwtool ·
If I wanted to see results I would put the cost of the twin plug heads and ignition to something that actually significantly increases my hp and torque, not pay $2000 to have a cleaner burn and slightly better response low down. If you want better response stroke it, inject it, blow it, whatever you like that REALLY works...if the vw motor was such a wonderful design, why didnt it have twin plugs to start with??? Bang for buck, I wouldnt post before and after dyno results either...could be a little embarrasing. The things we do to stay in a class with volvo's and mazda 626's. Hands up who is afraid of racing some quick cars(other than your vw's) and venturing out of the 1916 comfort zone. I know some of you more experienced drivers would relish the challenge(you know who). Bigger, better, faster motor, less expense and the satisfaction of beating quick cars!
You tell yourself something enough and you actually believe it regardless of what everyone else says. Besides what would you say to all that have followed.
hugs and kisses.
gayanne ·
vwtool wrote:If I wanted to see results I would put the cost of the twin plug heads and ignition to something that actually significantly increases my hp and torque, not pay $2000 to have a cleaner burn and slightly better response low down. If you want better response stroke it, inject it, blow it, whatever you like that REALLY works...if the vw motor was such a wonderful design, why didnt it have twin plugs to start with??? Bang for buck, I wouldnt post before and after dyno results either...could be a little embarrasing. The things we do to stay in a class with volvo's and mazda 626's. Hands up who is afraid of racing some quick cars(other than your vw's) and venturing out of the 1916 comfort zone. I know some of you more experienced drivers would relish the challenge(you know who). Bigger, better, faster motor, less expense and the satisfaction of beating quick cars!
You tell yourself something enough and you actually believe it regardless of what everyone else says. Besides what would you say to all that have followed.
hugs and kisses.
TextVWTool,that sums it up beatifully😀 JVLRacing
GregWard ·
So Vwtool, something that "REALLY" works huh? so have YOU done it? I'll answer that for you, of course not cause it's "not the norm!"
Another unfounded, unbacked, and as I said before, "disinformation"
Stroke it, sure I agree as far as torque goes, for what $$$?? Turbo it? Sure for what $$$?
What is your real name and what have you raced?
"The things we do to stay in a class of volvo's and mazda 626's" ............are you that ignorant?
I've raced BDA Escorts, Nissan Pulsar's with Turbo's, serious Datsuns, and other extremely fast Vw's, I beat Jeff Unwin in 5 races in a season, are you telling me his car is/was a piece of shit? Jeff's way is not my way as far as engine's go, but it doesn't mean I respect him any less for his achievements??? Ring him up, I can give you the number if you don't have it, and like me he will tell you, it was one of the most exciting and competitive sportsmanlike years in VW Racing history.......I've also come 8th out of 79cars including all the sports sedans of every manufacturer you can imagine, even the WRX's,mini's, V8 Celica's etc... with slicks at Buladelah, one of Australia's fastest hillclimbs... and I drove my car to the track, raced, won and drove home again.....just like I did last weekend........
1916 comfort zone? What a load of crap...
I choose to do what I want to do. no-one including my engine builder influences that, it is MY money after all.
But as I expected, here we go with the usual shit that I've seen for as many years as I've described in my last post.
Hey Vw tool, as you've said in your post, if the engine was such a fantastic design, then by your own admission, forgetting twin plugs as your sorry argument, so why wasn't it injected, blown or stroked?
Sounds to me like you'd better answer your own argument before trying to belittle someone else's.
Again, my previous post stands true, without ANY knowledge or research, someone tries to strike down other people's progress.
Did you not read my last post? are we not supposed to be helping each other and SHARING information.
I tell you who I'm going to help, a bloke called Nathan Abbott, who comes from a Datsun world, where Dyno talk is a laugh a minute and track placings show the real results, and because he has had nothing to do with this scene and the nonsense that it spouts, I hope he beats me this year, and I will be the first one to congratulate him and buy him a beer........
To Pete Wood, thanks mate, never met you, hope to though, cause you are the one VW person who actually grasped what I'm trying to say, these are AMAZING little machines, no matter who works on them and what engine you employ.
Come back to me Vwtool, cause I'd sure as hell like to make sure you have an entry form for Buladelah, so I'll photocopy it and send you one, gratis, no excuses, and if you beat me, I'll be a man and buy a fellow VW person a beer too, instead of being what your title suggests....
[Edited on 19/5/2005 by GregWard]
jakjones ·
You will be treated well on this Forum only if you join the 1916 brigade,there are several standard answers to different topics and as soon as you challenge these standard answers you will be cut down and treated like a Leppar.
Dasdubber ·
jakjones wrote:You will be treated well on this Forum only if you join the 1916 brigade,there are several standard answers to different topics and as soon as you challenge these standard answers you will be cut down and treated like a Leppar.
There may be a selected few with such standard answers, but remember that there are many others who encourage useful debate that can be backed by experience and results rather than heresay.....I hate when people generalise about how the "Forum" treats individuals - I am part of the "forum" but don't wish to be included in such a generalised statement.
Unlike far too many if I have no direct experience in a topic, I don't shoot off my mouth and speak $hit - I sit back, read, ask questions (not make unbacked statements), but otherwise stay quiet until the time comes when I can make some valid input. So I encourage people to provide input, but make sure you can back it up.
So lets get back to promoting thinking outside the square as stated already, encouraging people to do something different, and supporting those who are willing to share their experiences. Okay enough ranting from me, lets get some more info :duh
By the way jak this is not directed at you solely (only the first paragraph of my reply is)....it is related to everyone.
Alan
[Edited on 19-5-2005 by Dasdubber]
pete wood ·
jakjones wrote:You will be treated well on this Forum only if you join the 1916 brigade,there are several standard answers to different topics and as soon as you challenge these standard answers you will be cut down and treated like a Leppar.
Last time I look my car had a Subie in it Jak. Have you gone and swapped it over to a 1916 while I was out at dinner last night. :P
Speaking of which, Subies are just another form of VW boxer. Another way of thinking outside the square. Mine is stroked, bored, watercooled, quad cammed and EFIed. Unfortunately, there is no room for an extra spark plug. 🙁
Greg, I'd love to race it in hill climbs but I don't have the time. However, I have done two motorkhanas in it so far. Gave me a much better idea of how my car really works. Just like you say.
How many events have you done, vwtool and Jak?
vwtool ·
Greg,didnt you win the last event? You must have had your twin plugs fitted, if not then 1.why spend the dollars 2. How do you know how much difference they make.
Why are there no arguments between 2275cc drivers and other people on the forum, or any other engine capacity other than 1916.Why because no one else makes the sweeping statements about how good their engines are and how every modification subsequent to theirs is a waste of money.
The only reason I wrote what I did was in response to Bat69 telling everyone to put their money where their mouth is and come race with us! i wouldnt waste my money on twin plug heads because if I spend money I want to see the most improvement without sacraficing relaibility. This would also put me over 2000cc if I was not already there!
I have raced in Rallysprint, motokhana, khanacross, supersprint and drags. I lived the last 5 years in L.A and participated in various events for fun,and there are hardly any 1916cc cars competing.
Each to their own regarding engine choice and builder, although i would never make statements about the performance of any of my motors because actions speak louder than words. If I did, I wouold certainly have the figures scanned ready to post if someone asked!Besides it can only benifit Stan if you all actually show us how good the produst is.
And who thought friday was going to be long a tedious?
Max
GregWard ·
Vwtool,
Wow, talk about someone putting words in my mouth...
When did I ever mention my engine size? I never did because this is the shit that starts every single time.
"Why are there no arguments between 2275cc drivers and other people on the forum, or any other engine capacity other than 1916.Why because no one else makes the sweeping statements about how good their engines are and how every modification subsequent to theirs is a waste of money"
As for your above statement, I hope everyone here can see what a ridiculous paragraph that is.
If you're trying to infer I ever said anything like that, then it only backs up the animosity that certain individuals in the VW scene have toward each other...
Show me where I said anything bad about any size or for that matter, type, of engine.
My beef comes with people making as you say "sweeping statements" about how something is just crap, when they can't back up one iota of what they are saying....
No my car hasn't got twin plug heads on it yet....Bloody hell, I made that statement in the first reply on the first page!! They are ready to go and will be installed at the end of the year, as I've also said before.
Maybe I'll install them on my 2332cc engine instead?
Your posts come out and badmouth people's cars including mine (I don't care about the other people, they are big enough to speak for themselves) and rubbish the class that they are raced in, again, the perfect example of a VW person attacking another VW person, you went one better this time, not only rubbishing a product you have no knowledge of, but the cars and drivers themselves...
So, U2U me where to send that entry form for Buladelah, there are only a couple of corners otherwise it's flat out. Last time was 170kmh over the finish line.
I don't care what size your engine is, I'd love to see it run, doesn't matter what class you end up in.
vwtool ·
You are taking this a little personally Greg. You must be quiet at work. Apart from asking you if you won and had done your twin plugs, I have not mentioned you. I did say that some drivers would relish the challenge(you and craig), and you also said you would happily dyno your engine when it had the change, great!
Someone asks about twin plug heads and their benefits. Lots of people argue back and forth the pros and cons.
Not as an accusition, someone asks to see the benefits on paper. After all, vw stuff is expensive, and we all want that extra power.
All of a sudden some people get defensive and do not answer and keep telling how great they are, although still nothing on paper.
Now, what are people supposed to think. Especially those who are considering buying them.
Like I said before, It could only benefit the producer of the product if you, the people racing with them, show us why they are worth the money. People were begging Craig to show his results, not to have a go, but to see if they might be something worth purchasing to make their VW faster!
Now, after all that, I will ask how a bug with a close ratio box is doing 170km/h up a hill, or were you in a supersprint. Thats what hot bugs get down the straight at Eastern Creek.
Be back to answer any questions in a while...have to go weld up the new exhaust.
Max
[Edited on 20/5/2005 by vwtool]
dangerous ·
Hello Volksy Friends,
When I first started this post I was hoping to get some healthy discussion and also some data
about the twin plug conversion.
Well, I got the discussion...probably not all that healthy, but still interesting. I also got alot of good info too. It even drove me to do some more research.I have come to my own conclusions.
The only dyno test info I wanted was with the twin plug system switched from one to two plugs
and back to the other plug...using the same coils and other equipment,but maybe that test cant be possible. Its not a simple thing to achieve & the mixtures & timing would have to be optimised in each test. I realy cant see the point in comparing a 009 antique with a modern ignition, no matter how many plugs its got.
Anyhow, thanks to every one to contributed to the discussion.
At least from all this we have learnt that optimum tuning of any engine combo (on the dyno & whilst driving) always is the money best spent.
On another topic(but for seprate posts) I have been involved with VW air cooled combos as small & over square as 59X85.5, right up to 90X102. All performed very well, with no hessitation or missing,when tuned with the correct air fuel ratio throughout the rev range.The ones that performed the best had the best cylinder head flow.
[ Edited on 1-7-2006 by dangerous ]
jakjones ·
the only cars doing 170kph over the finish line at Buladelah are open wheelers and maybe 1 or 2 sports sedans.
Gregs speed at the finish would be more like 140kph.
correct me if I'm wrong please.
[Edited on 20/5/2005 by jakjones]
GregWard ·
Well Max, it wasn't me that made it personal it was you, I don't like being told my racing class is not worthy of anything, I don't like insinuations about stuff I've supposedly said about my engine, all sorts of words were put in my mouth.
I don't say that about anybody else who is in this hobby, no matter what they are doing.
I only replied to this at the beginning page to get people thinking about the subject, not "smoke and mirrors".
This is way off topic and really I haven't much more to say about it.
I don't post anything that I haven't had experience with first hand and can back up, now I'm told I'm not doing that speed at Bulahdelah!!
Hilarious, Peter Gumleys car can do 100mph in 1st gear, you think he's only gonna get 170kmh over the finish?
Anyone who can use a calculator can work this out.
GregWard wrote:Well Max, it wasn't me that made it personal it was you, I don't like being told my racing class is not worthy of anything, I don't like insinuations about stuff I've supposedly said about my engine, all sorts of words were put in my mouth.
I don't say that about anybody else who is in this hobby, no matter what they are doing.
Greg, please highlight the parts where I put words in your mouth and insinuations about stuff you have said. I have never even spoken to anyone with reference to you in my life, let alone the forum, except when I asked you if you have your twin plugs fitted to your car. Apart from seeing your name on the forum, the first I heard of Greg Ward was that you beat Craig in the last event.
The only reason I started this argument, as I have said before, was because Bat69 said..
QUOTE by Bat69
Maybe some of you old ladies could put the money your wasting in hot air and pay for my own twin plug heads. Im more then happy to donate my race beetle to be dynoed with or without twin plugs to see the advantages.
Or may be you could put that money your wasting in hot air into your own car and get out on the track and come race with the rest of us. Then you might see some real results.
So all the old ladies, when they have finished wasting money on hot air, if we spend some money on the car and go race with them, we might, only might see some Real results.
You cannot bait a hook with that much bait, and not expect a nibble, besides its Craig who posts the best comments and replies. I was really hoping to get him to retort by accepting the free dyno offer. Not to eliminate the hardyards, not to tune it, not to critisise it, just to see the difference between single and twin set up. Please tell me why everyone ignores the fact that people will naturally be cynical and need to see that a product works. The heads obviously do something otherwise no one would have bought them. Keep them a secret till Greg puts his on the dyno, its only hampering their sucess!
Craig, if your not going to play, atleast buzz your brother and get him to chime in.
[Edited on 20/5/2005 by vwtool]
jakjones ·
So 56 ya wacka is that graph suppose to prove to me his a speed , get real, I reckon his tacho is way out cause I spoke to a bloke in a very fast sports sedan and he said he was only doing 174kph at the finish line so go figure.
56astro ·
and again
:duh
pete wood ·
Jak,
Now the for the real question.
Did you ASK the sport sedan driver why he was going that speed?
maybe it was bad traction or the car was not running properly.
oh BTW, you have U2U.
jakjones ·
bad traction at 170kph pete dreaming again, I believe someone may be mistaken.
pete wood ·
back to the topic,
Greg, when do your new twin plug heads go on?
boof2332 ·
Well, I think I should frequent this part of the forum more often, havn't we all been having fun!
Hey Greg, are they going on the 1916 or the 2332?
Matt
GregWard ·
Jak, I think you're probably right, also talking about racing hillclimb is way off topic and I started that.
Pete, more to add at the end of the year, sooner if I can build another engine instead of pulling mine down now.
Matt, depends on which class I decide to race in? dunno yet...
mountainbug ·
Pete..
I found the link to Jim Feulings motor searoy once had:
Here's a bit about the man himself, (from shoptalk forums)
"Jim was a rare genious. An engineer of the highest caliber I remember going up to Ventura to see his aerotech quad 4 twin turbo olds years ago, made some crazy numbers like 1200 h.p out of a 2 liter. Then later a few years ago, I went up there to take a look at some weird 3 cylinder harley he was messin around with. A W3 3 cylinders 45 degrees apart strange thing. Go into my computer file and look up Fueling, I know I have a bunch of stuff Jim sent me, he was doing something with a VW I vaguely recall him telling me, I think it was somekind of 4 valve cylinder head thing he was prototyping to use on Harleys or maybe some other thing. If I remember right, he died of cancer back around Christmas 2002 so I don't know what happened to his shop" ---------------
Jim Feuling is an inventor, author, publisher, philosopher, pilot, motorcycle and automobile designer/builder/racer and leading-edge researcher/developer in the field of engine design and fluid dynamics. Jim founded Feuling R&D/Advanced Technologies in 1974. His experience with high-efficiency engines began at an early age. He started riding motorcycles at age 5 and flying aircraft at age 11. He tuned and raced his own motorcycles and won the California State TT Championship at 16. He graduated from high school in Honolulu, Hawaii, attended Southwestern College and The University of the Seven Seas. Jim served in the United States Army Special Forces. He subsequently began building and racing sports cars and off road cars. Jim scored many off-road racing victories. He was also awarded the prestigious SCORE "Mechanic of the Year" trophy in 1976. His racing engines, high performance components and inventions have been used worldwide, from Daytona to Monaco, from off-road racing to Formula One Grand Prix to the Indy 500. Jim¼s leading edge development work includes his company¼s R&D contracts with Chevrolet, Oldsmobile, Ford, Chrysler, Nissan, John Deere, Harley-Davidson and aircraft companies such as Cessna, Mooney and Quickie. In 1988 he received the "Outstanding Technical Achievement Award" from the National
Engineering Societies for his "clean sheet" design, development and manufacture of the 2.0L Oldsmobile "BE" Quad-4 racing engine used in the Oldsmobile Aerotech Research Vehicle (267.339 mph International Record, driven by A. J. Foyt). His radical design for the Oldsmobile BE 4-cylinder engine developed the highest specific power output of any automotive engine in history (over 1,270 hp from 121 cubic inches).
In addition to racing efforts, Jim also developed the engine for the American Honda high-mileage streamliner, capable of 500 MPG @ 55 mph, and developed the engine for the 2-place Q-2 aircraft, rated the world¼s most efficient. Another one of his highly-recognized products was the well-received 4-Valve cylinder head conversion for Harley-DavidsonÆ Evolution motorcycles. He has recently begun manufacturing his patented aluminum CENTERFIREÆ cylinder heads for Chevrolet 454 and Ford 460 truck engines. Jim is a member of the Society of Automotive Engineers, The American Society of Mechanical Engineers, The American Chemical Society, the International Society for Optical Engineering and a Senior Member of the Society of Manufacturing Engineers. He holds numerous international land speed records and is a member of the prestigious 300 MPH Chapter of the "Bonneville 200 MPH Club". The Feuling name has been closely associated with ultra-high efficiency, small-displacement engines, but he and his staff have years of experience with engines and powertrains of all sizes, from motorcycles to Indianapolis racing engines to hard-working big-rig diesels.
Jim is a consultant to a number of educational institutions. He also serves on the Board of Directors for the San Diego Automotive Museum and has served as a "Distinguished Speaker" in the SAE Industrial Lectureship Program. He is a very popular speaker and has made numerous presentations to SAE, ASME, IMA and SME. He has been a featured speaker at the Superflow Advanced Engine Technology Conference on four different occasions; beginning with the 1990 Superflow Advanced Engine Technology Conference on the topic of "Overlap Phenomenon in the Four-Stroke-Cycle Engine," again at the 1991 conference, where his subject was "High Efficiency Sound Attenuation for Internal Combustion Engines." He addressed the 1995 conference on the topic of "Mechanical Octanes" and the 1997 conference on his "ULEV High Performance Engine/Vehicle."
Jim is currently involved in numerous cutting-edge projects including his radical W3 Motorcycle. A "detonation chamber" engine design, EZEV/zero emissions equivalent vehicles, electronic aerodynamics and his awesome Bonneville Streamliner.
His hobbies include surfing, scuba diving, motorcycles, paranormal phenomenon, UFO¼s, Nikola Tesla and traveling to historic and mysterious places.
Jim has two sons, Daniel and Matthew. He and his wife Kathleen have a daughter, Theresa. They live in Southern California.
VWCOOL ·
Craig, if your not going to play, atleast buzz your brother and get him to chime in.
[Edited on 20/5/2005 by vwtool]
Okay: My next air-cooled Beetle-style engine will be a Stan Pobjoy twin-plugged 1916, due the sharply-improved drivability and throttle response and overall performance this configuration gives. Possibly with injection, (either Delco or Microtech - I know people who effectively tune both)
Is that enough chiming?!
[Edited on 24/5/2005 by VWCOOL]
[Edited on 24/5/2005 by VWCOOL]
fullnoise ·
A few years ago Greg showed me some of the research material he had collected on twin plug ignitions. This was before he had formed an opinion and before he'd even spent a cent on the idea. It is obviously a well trodden and well proven concept.
Greg is a lot better qualified to theorise on the subject than just about any of the hacks on this forum.
The man is a genius with carburetor, jetting, tuning and general understanding. He's raced and tuned a number of high compression engine combinations.
He understands the trade offs you have to live with when it comes to long duration cams, high compression with low octane fuel and the problems associated with excessive engine heat.
Those of us with modified aircooled engines try and combat these things with super-squish pistons, different combustion chamber shapes, different fuel and exotic cooling systems.
According to the literature the twin plug system should be a great benefit to an engine designed for it. But I don't think it should be treated as bolt-on horsepower.
There is a fair bit of us and them on this forum with respect to anything to do with the word "Pobjoy".
To make sure this forum actually contains useful content and not a slanging match can you all please praise, if not go easy on, the people, like Greg, who have the guts to experiment at their own expense?
CYA CT
Craig Torrens ·
dangerous wrote:, there is no advantage unless a plug or lead fails. I'd rather spend the money on a dyno tune or head work....but then you couldn't tell your mates you had twin plug heads...
See Sides, you will soon be able to tell your mates you have twin plugs !!😂😂
dangerous ·
dangerous wrote:Enough of the hype, how about some serious facts & dyno proof on this conversion. Correct me if I'm wrong, but if an engine it tuned to its optimal, there is no advantage unless a plug or lead fails. I'd rather spend the money on a dyno tune or head work....but then you couldn't tell your mates you had twin plug heads....Just the facts please, perhaps we can all learn something. Dont get me started on cryogenics! Damn those magic beans!
You should be a journalist Craig!
Quoting the WHOLE comment makes the story seem a little more clear.(stirer!)
A lot can happen in five years,
but I would still rather spend MY money on a dyno tune and head work.
Plus with my own engines,
my intake valve leaves no room for extra plugs,(54mm).
Unfortunately at the time no one was prepared to share any dyno information,
for what ever reason,(which you can see, was what I was after).
After some first hand discussions with (sharing)people who had the conversion,
I was told the engine was noticably smoother at the lower rpms with big cams,
but probably no more maximum power, if the fuel mixtures and timing were already optimised.
They did feel it was money well spent however.
Time will tell ,
but my current thinking is that there
may be SOME extra power in SOME combinations,
but "advantage per dollar spent" is STILL to be answered.
Some of my customers have asked me to do this machining
because they plan to use THEIR engine management to fire the plugs,
and so the added cost to do the work was just the machining plugs and leads.
I am always interested in trying different things,
just a shame I have had to wait so long for any dyno input.
....oh, and if you want this work done, send it to Stan!!
johny rotten ·
😂
I love this thread
Sides ·
Interesting thread this one hey... some good info buried in there between the usual crap and carry on.
But yeah - what dangerous says is about it... I'd always planned on going EFI, and putting twin plugs on the engine list seemed logical really... cost wasn't too much extra, and pretty simple to make the ECU deal with firing them.
Basically, my plan is to dyno and optimise the engine as it is now... 44 IDF's and single plugs with a Mallory CDI. Then when I go EFI it'lll be back to the dyno... most likely with just single plugs, then run an event or two before hooking up the second set and repeat.
btw I see that no-one's taken up the free dyno offer... wonder if there's any VW friendly types in Bris who'd donate time on their dyno ???
😉
My expectations are pretty conservative... I'm wanting for both the EFI and twin plugs to give better drivability and mid-range rather than increasing the top end. If it works out that way, AWESOME. If not, well it's something new learnt at really not very much cost.
Oh - and as to telling my mates I have twin plugs... well the non-racing ones are already massively jealous just at me having a race car, while the guys at the track get all excited about the dry sump system !!!
😂
JVLRacing ·
Its been a popcorn affair😂 2005 this topic started!
hellbugged ·
great plan Dave....will be great to see the progression and hopefully great results
vassy66T1 ·
I agree Daimo. Dave's bug (Sidery) is heading very nicely. Go hard Dave. Let's see what 8 plugs can do hey??
johny rotten ·
Dave
have you posted any pics of your dry sump system ?
its a topic thats always interested me
Sides ·
johny rotten wrote:Dave
have you posted any pics of your dry sump system ?
its a topic thats always interested me
Yeah, you know I actually haven't yet - been a bit slack in that regard !!!
Gotten a few questions on things like that tho, so might dig up some pics and put up a thread on the things I've done that are a bit different. Bit late for a "build thread" really, since the Jezebel's been together and busily competing for over 3 years now...
😉
Oh and cheers for comments Damo & Marcus... will definitely share how things turn out... 👍
JVLRacing ·
Sides wrote:
johny rotten wrote:Dave
have you posted any pics of your dry sump system ?
its a topic thats always interested me
Yeah, you know I actually haven't yet - been a bit slack in that regard !!!
Gotten a few questions on things like that tho, so might dig up some pics and put up a thread on the things I've done that are a bit different. Bit late for a "build thread" really, since the Jezebel's been together and busily competing for over 3 years now...
😉
Oh and cheers for comments Damo & Marcus... will definitely share how things turn out... 👍
people will be interested wat u have done with the car....spill the beens 😎
Super1302 ·
gee i guess the engineers at porsche and the like dont know much about this subject do they, hmmm, thats why they get paid the dollars and drive these nice mobiles with twin sparks, hmmm they must be bright sparks too..........
cheerio
SuperOwen ·
Have you ever looked in a 911 combustion chamber? Bit different to a vw.....
I wonder if it would be more effective on some of the old Berg semi hemi heads?
SuperOwen ·
And on another thought have porsche used twin plugs since they went 4 valve watercooled?
55slug ·
GT3 heads run a single plug in the centre of the chamber. They make OK power.
It is a four valve head though.
SuperOwen ·
Thats what I thought, nice tight combustion chamber means no need for a second plug.
Craig Torrens ·
SuperOwen wrote:And on another thought have porsche used twin plugs since they went 4 valve watercooled?
Whats your point ?
hellbugged ·
does it matter what shape the combustion chamber is if there are two flame fronts igniting from the centre (ish) of the chamber?
if the squish is good it will ignite yeah?
instead of one front travelling accross the area there are two fronts traveling outwards (as well as the small distance between the 2 ignition points)
SO does the poofteenth of a difference in ignition/burn completion count for better efficiency.............🤪
55slug ·
The porsche twin plug engines basically had a hemispherical head, two large valves forcing the plug to one side (like a VW head but the porsche has a symetrical chamber rather than a wedge).
I think the clincher is they ran dome or tent topped pistons, so without the twin plug set up they effectively would only ignite half the mixture, making them innefficient, so they went twin plugged to increase efficiencies. Basically it all works with that chamber and piston design.
mopar hemi chamber - new one !!
ian.mezz ·
everybody knows that you need bigger valves or more valves and a high energy spark, 😂🤪😂
Super1302 ·
SuperOwen wrote:Thats what I thought, nice tight combustion chamber means no need for a second plug.
better spark, better burn, gases all burnt better expansion, better economy, more tq and hp.😎
yeah
Super1302 ·
i know if i had the money i know which motor i would choose.
coletrickle ·
Sides wrote:btw I see that no-one's taken up the free dyno offer... wonder if there's any VW friendly types in Bris who'd donate time on their dyno ???
If your keen i'll check with my mate he has a dyno at his house down at logan village,Frosty and my self were gonna have a little tuning day down the track I'm sure he wouldn't mind.Other wise when i get the 2332 back togeather I'll see where u are at.
SuperOwen ·
Craig Torrens wrote:
SuperOwen wrote:And on another thought have porsche used twin plugs since they went 4 valve watercooled?
Whats your point ?
Point is twin plugs aren't required with an efficient chamber design, mind you theres no comparison between a new porsche and an old vw so no point afterall!!
fish26 ·
ian.mezz wrote:everybody knows that you need bigger valves or more valves and a high energy spark, 😂🤪😂
uuhmmm no, most of the time if the ports are left alone the large valve just gets in the way of the incoming mixture, but yes, more valves depending on the chamber shape, piston top, engine configuration,ie overhead cam, together with direct fire ignition for a more efficient burn.
Hemi, symmetrical chamber would be a good candidate for twin spark in a vw head, I would assume hemi is the chamber choice for Stan?
There are a lot of chamber shapes that work with the type 1 head for the specific purpose of their uses combined with cam selection. "D", kidney, oval, wedge, etc.
There are also head tweeks that can be applied ie, twin spark, tight deck, sunken valve, groove, etc.
I am currently messing around with a certain head, cam, ignition combo that I hope to dyno back to back with a stock valve head on a fairly racy 1776.
I will not knock the twin spark, because I know it works in certain applications, however I will not say its better than a well set up single spark head, only way to know if its at all better, is back to back figures which we don't seem to be seeing from anybody and this thread is absolutely USELESS without that.
I hope its not friggin pride getting in the way.
I think Porsche engineers know what they are talking about.
azza81 ·
i had a twin ignition base motor in my manx
awesome up the beach extra touqe low in the revs
and if you hit water it didnt miss
you had to drown a lot of plugs for that to happen
spdterence ·
Testing this should be really simple though no? Just do a dyno run and then take off the bottom set of leads and run again. I assume that is how it would be done.
From the engineering I know this is a sound concept - but would still like to see if it produced any discernable difference.
On a slightly different angle - can a dyno measure how quickly a motor responds to a new fuel load? Bear with me - say if you are pulling out of a corner and you dump a heavy fuel load into the cylinder - how the combustion chamber copes with that large amount of fuel ie - if it can ignite the fuel load quickly and effeciently - then this would effect driveability?
Whereas - just plonking a motor on a dyno and letting it build up revs in a moderated way doesn't reflect how a car is driven in reality to my way of thinking.
Just a thought. Terry
westi ·
simply taking leads of sound's good .if it was the same combo.but knowing stan.
i dare say that a twin plug set up compared to a single plug set up would more than likely have a diferent cam.
beause there is know point burning more fuel if there ain't any extra in there.
bigger spark need's more fuel which a smaller cam might not allow.
just thowing it out there,but there will be some truth to the madness.😵💫
there would be no point putting a kick arse ignition on a car if you don't have any fuel to burn.