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Humpty's finally got off his arse and begun a real drag car project!

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humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#802181
Stanley wrote:Also re-read the bit where he bags 4 barrel carbs......🤪
He sure does beat on the Dellorto drum and kick the shite out of Holley's!....

Oh man.... More detail from Nick on how he suggests I do this.... Same system he used back in the day when this carb I have was on one of his cars.... My god is a strange method!!!????..... But simple all the same..... I'll be sure to post some pics up once I have it all together...
FUCH your early!

http://www.noh2o.org/

ian.mezz I never said, I could write or spell

3,913 posts · joined Sep 2004 ·

#802209
I think I seen some where on here how to make your holley work its best???? I am sure there was a vid , but I just cant find it.🤪🙅🤪

http://www.lowbugget.com/turbo_new_page_link.html
😂🤪😂🤪😂
car forums. where a lot of peoples good intentions end up taking a good old car off the road forever never ever to see the road again. 🥲

pete wood 23 Windows of Awesome

6,828 posts · joined Jan 2004 ·

#802646
can someone clue me up on why 4 barrel drawthrough setups are so popular? I don't get it myself, I mean I can see the cheapness factor, but why not run blowthrough or EFI and then at least you can use an intercooler?
"stoopid is stronger than axles"
http://drivingnotpolishing.blogspot.com.au/

humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#802666
pete wood wrote:can someone clue me up on why 4 barrel drawthrough setups are so popular? I don't get it myself, I mean I can see the cheapness factor, but why not run blowthrough or EFI and then at least you can use an intercooler?
As most of the draw-through crowd are into drag racing, intercooled/blow-through set-ups offer little advantage if any.... And not everyone wants or needs the hassles/complexities associated with the blow-through either.... My car makes plenty of boost, drives very nicely on the street, runs very cool and was far easier to build... My bus on the other hand, is going to the efi/blow-through... But the reasons are simple... It's a driver, not a quarter miler and I don't like the idea of a turbo in the engine bay with the fuel tank...

The sidedraft v holley issue is a totally different argument though.... Some believe that the holley offers better fueling across the range in this config. With a larger float bowl, more progressive circuits and cheaper in the US than the sidedraft carbs, I can see the advantage... The problems I have with them, is that they are very hard to get under a decklid.... Even a conventionally propped one like mine.... And they are not really any cheaper in this country.
FUCH your early!

http://www.noh2o.org/

Stanley I guess the reward is in the doing of it

4,523 posts · joined Mar 2003 ·

#802770
As Simon says (sorry for the pun) the Holley's, in my case the 600, has 2 big float bowls which is perfect for methanol. The disadvantage with the Holley is they are difficult to tune over a wide rev range hence the reason why you see mods for boost referencing the power valve amongst others. In my case it will spend 90% of its life at WOT so that's where it is tuned with a small PV and big jets. Track time will tell.

The other disadvantage in draw through is the fact that a down draught Holley needs the fuel to change direction from vert to horizontal which allows the fuel to come out of suspension. If this was the case a side draught like Simons would be more efficient. I argue that when any fuel hits a compressor wheel doing X000 RPM that it's going to fling the majority to the outside and come out of suspension regardless.

In saying all that you're probably wondering why the hell go for a Holley then. The reason I went Holley is mainly because I had hoped to have a blower fitted but didn't get it finished. The SU while a good carb for the street in my opinion suffered at the track due to not having an accelerator pump. There are plenty of people using Holleys but ask me after Warwick and I’ll tell if it was a good move.

Keep up the good work Simon.

humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#803763
Upon Nick's help with this, I am refitting the Malpassi that I had fitted way back at the start of this project, and thrown out the Holley FPR's.... Stupid farka I am.... I should have listened to Nick's advise from the start!!!!

But anyway... How Nick has suggested I fit the Malpassi is a very curious one for me, but I have been informed by my brother (who is also a very clever dude), that the method Nick has suggested is also how Subaru do it.... But I digress...

The questions I ask those that a cleverer than I, are as follows...

In the image below, you can see that I have relocated the FP gauge to the fuel inlet point on the DCOE.... Anyone have any issues with this location?




Next I give you the Malpassi FPR location....



Likewise, can anyone see a problem with mounting it here?... Apart from the minor obstruction to the oil filler cap and breather point?

And before you ask.... Yes the FPR outlets are looped on purpose... I'm not going to use them on this set-up....
FUCH your early!

http://www.noh2o.org/

Stanley I guess the reward is in the doing of it

4,523 posts · joined Mar 2003 ·

#803820
Having the gauge at the inlet IN the carb will give you a true pressure at the inlet when the fuel is flowing. Mine is at the pump and won't give an accurate reading due to pressure drop when the fuel flows.

humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#803861
Thanks for that Andrew.... I appreciate the advise everyone is offering here....
All I need now is to source a suitable 'T' fitting to connect the FPR to the fuel feed and we are ready to rock... If it all works as planned, I'll pull the FPR and plug the outlets with some grub screws.... Next job is make up a vacuum chamber so I can run the various vac/boost componenets off one source.... T'ing off the manifold/turbo line is becoming problematic....

Here's hoping!
FUCH your early!

http://www.noh2o.org/

humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#804348
Latest update....

The story so far....

As you guys know, I've been having some issues with fuel pressure... It seems that since I changed the system to a 'dead head' setup instead of the previous 'return' setup, I have way too much fuel pressure and the Holley FPR's that I have tried (and was told would do the job), have not coped.... So after consulting may turbo VW peeps around the globe, I have come to the conclusion that nobody has any clue about turbo fuel systems, and the fool proof setting up of them.... What works for one dude, may not work for another.... I have proved this, as I have attempted 4 different set-ups and none have done the job yet.... But its funny how the world turns...

After chatting to Nick about this problem, I have redone the system again and gone back to the original set-up I had fitted way back at the start.... But with a curious twist.... As some of you may remember, the carb and manifold I have on my car actually came from Nick... I think it was used on his one of his street cars from earlier this century.... So he should know what system worked best for this carb.... And here it is....



If you look directly below the carb velocity stacks you will see the Malpassi rising rate fuel pressure regulator (FPR)... You may notice that the outlets on the carb are "capped".... Weird huh?.... I thought so too... So here's an explanation on how this system works.... The fuel from the pump goes directly to the carb.... No regulation (at least in the conventional sense).... Spliced into the line to the carb, the fuel is t'ed off to the FPR fuel inlet.... From the FPR the fuel is then returned to the tank... The flow of which is controlled by the boost reference port at the top of the FPR.... Fuel pressure will be set quite low at idle.... Like 2psi low.... As boost rises, the FPR pressure also rises, which restricts the flow of fuel back to the tank, in turn the fuel volume and pressure increases the flow to the carb....

I will get an accurate pressure measurement from the FP gauge I have fitted to the carb fuel intake...



To make all this happen I needed to create constant source for the FPR, iginition MAP and the boost gauge to get their respective vacuum/boost signals from.... The method I had before was getting messy with too many vacuum lines t'ing off the main line..... So I made a vacuum chamber with it's feed from a port on the intake manifold.... The FPR, the ignition and the boost gauge all get their signals from there.





Haven't started it yet.... Need to get a new car battery... Noticed a nice little Optima battery in Morgans' car at Portland earlier this year.... Might sell a kidney and buy one of those...
FUCH your early!

http://www.noh2o.org/

humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#810203
Finally got back to the car today.... Seems all my time has been focused on getting the "Free'n'Easy" sorted ( http://www.noh2o.org/viewtopic.php?t=1742 ) and working on other peoples VW's.... Everyone says I should do this sort of stuff for a living.... But if I did I reckon I'd tire of it pretty quickly.... I know that's what happened when I was a graphic designer and that's what's happened now I'm an art teacher!!!!..... But I digress....

The POS is alive once more!!!!

Now its back to reality....

I went through the usual checks prior to starting the car after modifications.... Very nervous moments I can tell you.... But all looked good.... Got the LC-1 calibrated, the FPR was seeing pressure and the boost gauge was all lit up...

So I turned the key.... Fired up almost straight away... Got up to temp nicely and idle settled pretty quickly.... If a little high...

Then it was time check things out.....

The boost gauge was not reading anything.... It's just flashing at me...???
Figured out the plug in the back of it is a little sketchy.... Fixed that with a little tape....

Still no boost.... Hmmmmm?

It all worked fine last time.... Before I fitted the gauge.... Previously the laptop was telling me the engine was producing boost, so whats changed?

The snappy boost/vacuum manifold I made.... Can't tell if its leaking, so I plugged the new lappy in, config'ed the COM's port to read the Megajolt.... All looked nice..... But..... No boost?.... So the manifold could be the suspect.... Gonna unplug it and fit the boost line directly to the ignition as before and see what's happening.... If both the Megajolt and the gauge see boost, we know the manifold is the issue... At this late stage I will go back to the old system and just 'T' everything off the one intake manifold port....

The next thing I have to tell is, the Innovate LC-1 is working a treat.... After going through the calibration process, the gauge reads loud and clear... At idle the engine is running very fat at 10.9-11.9.... At revs it seems to be peaking at around 13.5-14.5.... Which is about bang on.... It always did run strong and clean under power, so that's good news... And I knew my idle mixture was way rich before I fitted the LC-1, so that's further confirmation... Gotta see what I can do about the rich mixture at idle...

And finally.... Nick's idea for the fuel system seems to be working out.... As I can't see any boost at the moment, I suspect the referencing is not working either.... But I have the fuel pressure at idle sitting around 2.5psi.... Good enough for now....

Having a cuppa right now... Will let the car cool down and pull the vacuum chamber from the circuit and give it another shot.... If the boost returns, I know that's that problem sorted.... If the FPR see's boost also, that's further confirmation....

Here's hoping I have some good news later tonight!!!!
FUCH your early!

http://www.noh2o.org/

Stanley I guess the reward is in the doing of it

4,523 posts · joined Mar 2003 ·

#810421
Well?

humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#810439
Got the boost referencing happening, the FPR is a little erratic.... I think the pump might be over powering the FPR.... Changed out the air's from 150's to 180's.... A big jump I know, but it's all I have.... Idles are currently 55F8's and I don't have anything smaller.... So will stick with that for now.... The wiring in the engine bay and rear cabin is done.... Just finishing up the front and dash and we are good to go.... Can't get the shift light to work... Suspect it might need to be calibrated via the megajolt.... No time tonight or tomorrow night.... Jobs to do on Wednesday morning are.... Finish off the wiring, see if the tach and shiftlight are working, fit larger rear tyres and get a wheel alignment..... Then its off to the drags on Wednesday night.... I'll be there to have a blast.... Even if the gauges and shift light aren't working god damn it!
FUCH your early!

http://www.noh2o.org/

Dero Officially Full-On Dubber

227 posts · joined May 2005 ·

#810447
Wednesday eh... think i might sneak down and check it out 🥷

reub VWRX is gone...

2,054 posts · joined Sep 2002 ·

#810497
Bugger... I won't be down ...
Look forward to the post drag update dude. 👍
Reub

matberry Moderator Go hard or go home

8,114 posts · joined Mar 2006 ·

#810556
Good luck Simon, hope it goes well.
Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE

humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#810559
Did a two hour short course on setting up a TIG welder this arvo.... Thanks to the WA Ed Dept for that.... 😘

Sol I got home at a reasonable time this eve.... I got into the shed for a bit before I head out tonight to an art exhibition opening.... It's a busy time in Freo I can tell you!!!!

Finshed the wiring under the dash... Got the Monster Tach and the boost gauge sorted.... Even have the dash lights working all the extra gauges.... Still no shift light.... Might see if I can run that off the tacho instead of the Megajolt....

Started the POS and the idle is much better after the air jet upgrade.... AFR's are good.... Still fat, but better the caution I say.... Got the car booked in for a wheel alignment and some big ass 205/70-15 Conti's for the rear...

I have no clue as to how the car will go.... Hope I can keep the red mist at bay and ease my way into setting the car up.... Will keep you guys posted on how we go....

Cheers fellas.....

PS:.... Bring the Bus out Joel.... My bro is racing the BD23!
FUCH your early!

http://www.noh2o.org/

humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#810996
Well that was a bit of a fizzer....

Couldn't get any boost and the ignition was failing...

Couldn't quite figure it out.... Tried everything I could think of...

After two very crappy runs with nothing but coughing and farting, I put the car on the trailer.... Then my little brother and I have a chat about it on the way home... He watched my shocking runs and said that the car was dumping a heap of fuel as the car was bucking about... And I'm sure I noticed a 9 on the AFR meter at one point, which leads me to believe that I'm getting way too much fuel through.... Following my little bro's observation and his theory that its a fuel related issue, (I felt it was ignition based) I have come to conclusion that as the engine begins to build boost, the FPR (fuel pressure regulator) is ramping up the flow of fuel... This then proceeds to kill the spark... In an earlier post I also mentioned the point that the FPR can not get the fuel pressure low enough... Between 4-6psi at all times.... More constant than any previous fuel system incarnation but still way too high, so I'm sure that's not helping the issue....

Now to further support this theory, I had found that once the runs were completed, the car continued to misbehave on the way back to the pits and continue to run poorly in the pits for some time... Only after the car had idled for a while and was aloud to settle down, did the ignition begin to behave as it should.... Still no boost being registered, but at least the idle was ok....

So what do you guys reckon?

I think tomorrow I'll pull the boost hose to the FPR off and see what the car does... If the fueling settles down and the car produces boost as it has done in the past, then I think we may have the problem solved and its back to the track next week... If not, I'll try redoing the vacuum/boost lines.... Starting with putting the solid lines back in (currently they are all soft lines)... But I think I might remake the 'T' manifold.... Don't like how the current one fits and I know I could do a much neater job of the vac/boost port setup... One separate port for each referenced appliance me thinks....

Back into the shed tomorrow...
FUCH your early!

http://www.noh2o.org/

Stanley I guess the reward is in the doing of it

4,523 posts · joined Mar 2003 ·

#811004
Bad luck Simon.

Is it fuel pressure related or just too much fuel ie jets?
and is it running that bad you can't put your boot in to build boost or is this another issue?


Hang in there mate

matberry Moderator Go hard or go home

8,114 posts · joined Mar 2006 ·

#811015
Bummer

Sounds like your on the right track to me, too much fuel....but why.....

Surely Nick has some idea's.

Yes to the individual ports for maniflod sensors IMO.
Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE

dangerous 23 Windows of Awesome

5,901 posts · joined Jan 2005 ·

#811034
humpty wrote:In an earlier post I also mentioned the point that the FPR can not get the fuel pressure low enough... Between 4-6psi at all times.... More constant than any previous fuel system incarnation but still way too high, so I'm sure that's not helping the issue....
I would say that is your problem there.
It is well known that webers and dells dont like high fuel pressures,
but with your rising rate reg, that will probably be too much
.
If it does not actually flood,
the bowl level WILL artificially be over full,
and muck up everything.

For example the emulsions rely on the fuel level to be correct
to work their intended way.

I tried a rising rate reg on my Holley years ago
and it was jut too much pressure when boost was applied, (did as you describe)
so went back to a basic blue reg for each bowl.
(the holley needle valves could handle 6psi)

This is not to say it shouldn't work,
but you may have to start lower(say 1.5 to 3psi?),
and limit total pressure under boost to something more realistic.
You should be able to simulate this with an air reg without even running the car.

When the plugs get too fouled,
they may never recover, even when cleaned.

That black carbon can track the spark to earth and require plug replacement.
westi wrote:That's mad Alan.

trickysimon 100km/h is only 9 seconds away

1,473 posts · joined Dec 2007 ·

#811046
FWIW, all the R31 Skyline/ VL turbo people down here cannot stand the Malpassi's.
Quote from a local forum. "Also, if that fuel reg is a malpassi, fuck it off and put a stock one on. id say that would be half your troubles. those things are shit house"

humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#811047
Thanks for the words of advise there guys.... The more I think about it the more I agree with the idea Dave... I know webers (like dells) don't do high pressure.... Everywhere I look suggests 3-3.5psi max..... The over fueling is killing the spark with poor performance following.... Nick suggested the FPR should be able to get it down to 1-1.5 PSI, but my FPR can not.... I suspect the pump is actually producing too much pressure.... I could source another pump with a lower limit, or I might fit another FPR and set the max pressure at a higher level.... Say 8psi.... Then let the malpassi control the referenced pressure at the carb....

Off to get some more plugs and maybe another pump....
FUCH your early!

http://www.noh2o.org/

SuperOwen Fahrvergnugen

868 posts · joined Jan 2009 ·

#811070
I can't see why you need a rising rate setup in a draw through config. Just keep it simple, bypass regulator set at a constant pressure and let the carb work as intended.

humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#811102
SuperOwen wrote:I can't see why you need a rising rate setup in a draw through config. Just keep it simple, bypass regulator set at a constant pressure and let the carb work as intended.
Been there, tried that, didn't work.... I think the reason it didn't work for me is more down to the pump I have.... Its a Holley Blue... Way too powerful for a conventional draw-through set-up... No regulator on the planet (as far as I could find/afford anyway) could get the pressure low enough for the weber...

Gonna stick one of my Holley FPR's inline before the Malpassi in an attempt to drop the pressure a little... Hopefully I can then get the Malpassi to regulate down the 1psi at idle, and boost reference to the level the Holley FPR is set too...
FUCH your early!

http://www.noh2o.org/

Boostn Wolfsburg Wizard

657 posts · joined Apr 2005 ·

#811124
hey simon,
what size fuel lines do you have? up and back?
VOLLKOMMEN ART
nick@vollkommenart.com

Speed and Style

Boostn Wolfsburg Wizard

657 posts · joined Apr 2005 ·

#811125
SuperOwen wrote:I can't see why you need a rising rate setup in a draw through config. Just keep it simple, bypass regulator set at a constant pressure and let the carb work as intended.
The bowl will empty [on boost] quicker than the holley blue can get past the 2.5 needle valve.
VOLLKOMMEN ART
nick@vollkommenart.com

Speed and Style

humpty Bishop of Volkswagenism

3,336 posts · joined Sep 2002 ·

#811130
Boostn wrote:hey simon,
what size fuel lines do you have? up and back?
12mm ID from the tank to the filter (12mmID tank fitting) then to the pump, 10mmID line to 3/8 hardline to the rear, 10mmID to the FPR/Carb (as per the previous pics), via 3/8 'T' return, to 10mmID hardline back to the top of the tank...

So basically 10mmID for the most part in both directions....
FUCH your early!

http://www.noh2o.org/

Boostn Wolfsburg Wizard

657 posts · joined Apr 2005 ·

#811133
MMMM,

I always ran 1/2'' copper.
It could be the reason you can't get the pressure down?
VOLLKOMMEN ART
nick@vollkommenart.com

Speed and Style

Boostn Wolfsburg Wizard

657 posts · joined Apr 2005 ·

#811134
does the mallpassie change the fuel pressure when you adjust the screw?
VOLLKOMMEN ART
nick@vollkommenart.com

Speed and Style