Around the traps I have heard some talk about the fact that aircooled VWs with 5 speeds can overheat. On the face of it, to a non-mechanical person like me, this doesn't make sense. So I'd like to put forward why I think it doesn't make sense, and would then appreciate people's input as to whether my thinking is right or wrong.
Please note that none of the engine speeds and such like here are meant to be real, but are just being used for the purposes of illustration.
Say I have a five speed that does the following speeds at the following rpm
According to some of what is said, the car may overheat in 5th, even though the engine rpm is much lower than it would be doing the same speed in 4th.
I have heard it said that it is because the fan is running slower, but surely this would mean that it is as likely to overheat doing 80km/h in 4th because it is doing the same rpm. I would have thought if anything the engine would run slightly cooler because of the extra air flowing underneath the car past the sump at the higher speed.
In terms of the engine working harder, certainly at a higher speed the car is doing more work in pushing air out of the way, but I would have thought his was accounted for in the engine rpm.
I look forward to hearing your thoughts.
Cheers
Craig
ibmoknegawsklov ·
Due to torque multiplication with the lower 4th gear, effective engine load is less in 4th at 80kph than at 110kph in 5th.........not to mention drag, it multiplies rapidly as speed increases. Now with a nice water cooled engine
your thermostat will keep your engine happily at correct temprature as long as your radiator cools eficiantly........A cylinder head temp gauge can be a usefull addition for an air cooled motor if you want to be sure.
matberry ·
A proper 5 speed conversion will give you closer ratios for a higher performance engine and 5th gear ratios will end up similar to what 4th gear was. So in this case no probs.
But the cooling issue is valid, basically it will always require the same amount of energy (measured in Btu's) to push your car through the air at a given speed, this energy cames from burning fuel, so at the same speed, it doesn't matter if it's a 1200cc stocker or a 2332 fire breather, the std cooling should do the job. VW engineers designed the cooling system to function at a designed set of parameters, change these and things get complicated. The way I see it, if you now lower the engine speed, the engines ability to make the same power changes as we may (for example) fall below the power output of the engine that is required for that speed, also the cooling fan speed is reduced thus giving us a situation where the engine is working harder but getting cooled less.....I think that makes sense 🙂.
btw, matt, would a good oil cooling system be a way to sidestep this a little?
Barnabie ·
Thanks Matt, its not my thread, but that certainly answers questions I had 😁
Craig S ·
Fair enough, I think I sorta kinda understand, in my own simple way.
Essentially what you're saying then is that a water cooled engine would also be producing more heat in the same circumstances (i.e. 5th at 110km/h), but the cooling system would step up to the job either through the fans coming on or due to the greater air flow through the radiator (by achieving greater heat reduction), or a mixture of both.
Would I therefore be correct in suggesting that this is actually a shortcoming of the aircooled concept (if you consider having lower rpms at higher speeds to be desireable (e.g. for noise, engine wear and fuel economy))? Or have I misunderstood and I'm wide of the mark 🤓
Thanks for the replies.
matberry ·
Not in my opinion Pete, oil is aour secondary cooling, air is primary. A bigger oil cooler would help reduce the oil temp, but the problem would be the actual heads, bigger fins (ie more cooling area) and/or more air would help but it's beyond me to advise on this one😵. Heaps of r&d required I'd say.
Joel ·
Agree with Matt, the oil temp can be as low u want but it wont effect head temp much, and head temp is what comes up when the engines under load
bajachris88 ·
If you worried about fan speeds being slower... retrofit a smaller generator pulley to speed it up. Type 3 style tinwear under the cooling fins is suppose to help markedly.
Perhaps due to lack of availability of stock belt drive setups, you might want to do a synchronous belt conversion and seam weld the vanes of the fan.
The key way setup on the generator looks very similar to those of timing belt pulleys form your average toyota style DOHC engine. (i will check at home for you).
and you can get vw pulleys that will bolt straight on the crank that are synchronous.
ian.mezz ·
If you want a 5 speed that runs good by a Hyundai😂
Joel ·
bajachris88 wrote:Type 3 style tinwear under the cooling fins is suppose to help markedly.
That ones an interwebz myth, and completely untrue
"cooltins" are for type3 pancake motors only and dont work properly on upright
matberry ·
Joel wrote:
bajachris88 wrote:Type 3 style tinwear under the cooling fins is suppose to help markedly.
That ones an interwebz myth, and completely untrue
"cooltins" are for type3 pancake motors only and dont work properly on upright
x2
dangerous ·
Daimo found his ran cooler and got better economy.
And that was with a 0.82 fifth and 3.88.(way taller than the stock L-Bug 0.93)
I agree though that if you went too far, there may be issues.
I thought Daimos was going to be too tall, but he said it is great.
Mind you it has twice the stock power too.
Joel ·
After going for a spin in Daimos old bug last year, I gotta say that tranny is geared to perfection but Like Dave said his engine has the torque to use it
expecting a stockish motor to run with the same setup would be kicking sqaure in the balls
Phil74Camper ·
ian.mezz wrote:If you want a 5 speed that runs good by a Hyundai😂
You're kidding Ian. Do you wave at all the 5-speed VW Golfs that overtake you? What about the later 6-speed Golfs? Or the ones with the 7-speed DSG?
I think this one is a myth. Following their train of thought - you put in a taller 5th gear. The engine is turning slower at the same speed. Therefore the fan is turning slower too. Therefore the engine overheats!
What they forget is that the engine turning more slowly is doing less work. It's burning less fuel, both per distance and per time, so it isn't making as much heat. VW engines produce their best torque at lower RPMs anyway. Think about it - imagine a stock Beetle travelling at say 80 km/h in 3rd. Leave it in third for 15 min. How hot does it get? Now shift to fourth. Same road speed, and now the fan is turning slower. But does it run hotter still? Of course not.
The air-cooled VW/Porsche 914 came with a 5-speed as standard. VW/Porsche Austria used this gearbox in their rally Superbugs in the early 1970s.
BOLLOCKS! Aircooled VW's have a 5th gear as standard but they call it 4th! Yes thats right, 4th gear is an overdrive. A taller final drive ratio (diff) or taller tyres would create the same situation if it were true. 🙅
hellbugged ·
oh dear 🙄
Phil74Camper ·
The fact that a Beetle's 4th gear is an overdrive is irrelevant. What has the ratio got to go with the number of speeds?? Anyway, it's only an 'overdrive' into the diff. To the wheels, you then multiply by the diff ratio. I suppose you know for example that the auto Kombi's 3rd (top) gear is EXACTLY 1:1. So how many speeds does it have?
You can easily build a Rally Beetle 914 gearbox with all 5 gears above 1:1 - all close ratio speeds and NO overdrive. By your logic it isn't a 5-speed!
However you are right, you CAN create the same cooler situation at highway speeds with a taller diff, or taller tyres. VW did exactly that with their diff ratio, which got taller over the years. Make the engine turn slower at a given speed and it runs cooler, not hotter.
matberry ·
🙄
hellbugged ·
so all modern cars are geared to do cruising speed just above idle 🙅.........or is this debate about wether it's possible to OVER GEAR a vehicle reguardless of wether it has 3, 4, 5, 6 or even 36 forward speeds❗
btw, matt, would a good oil cooling system be a way to sidestep this a little?
dam you bet me to it 😂
yes a higher ratio final drive will make a 5 speed practical as 5 is the new 4 and 4 is the new 3.5 lol
vlad01 ·
hellbugged wrote:so all modern cars are geared to do cruising speed just above idle 🙅
Are you a vw person?
cars now are water pumpers and collect air into the rad by speeding through the air. Engine rpm is irrelevant in this instance.
pete wood ·
Vlad, do you realize who you are talking to? You might end up looking a little silly.
Daimo knows his stuff.
matberry ·
😂😂😂😂😂😂
Well......Daimo.........Are you a VW person???🤪
Joel ·
😂
Priceless
hellbugged ·
😊.......a very embarrased one now ❗
Keith Haeusler ·
Hi all,
This is my real life experience with taller top gear in a bug. In the early 90`s good mate had 68 bug, 2165cc,8.6:1 ida etc. Ran awesome. Never over heated oil or heads.
Changed to irs, stock L box, still good albeit lost a little bit of zippy-ness. Broke box, fitted .82 top with 3.88. Engine always ran hot in 4th gear and felt lazy.
Swap back to .93 top and problem went away.
I think the VW engineers knew what the score was.
Again, this is just what we found with this combo.
Regards, Keith
vlad01 ·
yes that about right.
Sides ·
hellbugged wrote:😊.......a very embarrased one now ❗
Awww... someone's made Daimo blush !!!
Gotta say tho that the last few posts of this thread are gold...
😂
As most everything else, it's all about the combo... VW stuffed around with gear ratios constantly, but they were all relatively minor changes... and the revs in top gear never dropped a huge amount... presumably to keep it all balanced.
If I was going to build a 5 speed, I think I'd be keeping 5th fairly close to a stock L box (say 0.85 - 0.90 x 3.88) and then spacing all the others to get a close ratio box that was still happy on the freeway. More fun, but still practical.
Daimo I know put a lot of thought into selecting his ratios, and all of that was AFTER he knew exactly how his engine behaved in the real world... and yeah, he came up with what looks to be a bl@@dy good result.
👍
ttriebler ·
Hey interesting discussion on final drive ratio guys.
I am about to start testing (and later on marketing) Subie 5 speeds for aircooled motors (fitted with my adaptor plate and flywheel combo to suit.)
I will most likely have to get a combination of gears and final drive ratios together that is 'one size fits all' for most aircooled customers wanting to fit a 5 speed.
Given that most of these would be fairly hypo 2 litre motors with either BIG cams and twin carbs or a turbo kit, what are the thoughts about getting the gearing where it needs to sit? Or is having a 'one size fits all' the impossible dream.....
Was thinking :
3.083 1st gear, 2.062 2nd gear, 1.545 3rd gear, 1.151 4th gear, 0.825 5th gear.
Final drive choice of 3.9, 4.1 or 4.4 ( I'm suggesting 3.9)
Other 5th gears available are : 0.972, 0.738, 0.78, 0.871.
Helical LSD
Craig Torrens ·
What diff ratio and 4th gear ratio did the 76 bug come out with ?? That will give you a clue 👍
Phil74Camper ·
Volkswagen/Porsche Salzburg (Austria) built 'factory' VW Superbug rally cars in the 1970s. They used mildly overbored stock cylinders (85.9mm) and a stock crank to make 1599cc. Dry sump, twin 46IDA Webers, big intake valves and stock exhaust valves (!), porting and a secret cam produced 126 bhp at 6,000 rpm. They fitted a 5-speed Porsche 914 gearbox, turned backwards obviously.
It used a 4.429 diff with 80% limited slip. Their ratios, and speeds achieved in gear at 6,500 rpm with 165-15 tyres, were:
What about power pulleys? Don't they slow the fan down? wouldn't that make a difference to cooling! Just a thought.
Phil74Camper ·
The Salzburg Rally team did not use power pulleys on their full-on race cars. They used the stock steel VW pulley. They knew what they were doing - these engines made over 120 hp from just 1600cc.
See how they also used the stock VW muffler and heater boxes. They spent their money on parts that worked - check out that triple-gear dry sump oil pump! - not on chromie parts that do nothing.
Yes power pulleys slow down the fan (and the generator). Not what you want to do.
Joel ·
Power pulleys dont belong on street engines, theyre fine on the strip where the engine revs beyond what the stock fan was designed for but a street engine will run hotter and the power they actually free up isnt even noticable
A mates 70 bug had one and finding the right size belt was a mission
Phil74Camper ·
Quite right Joel. To do it properly, you would carefully braze or weld the fan tabs so it can't come apart, then use the stock steel pulley and rev it as much as you want. Gene Berg used to sell stock welded fans. And you can use stock VW belts.
Power pulleys belong in the box with the billet distributor clamps, transparent distributor caps, chrome generator pulleys, brightly coloured coils, plastic heater hoses and all the other pretty bits that don't work as well as the stock VW parts.
hellbugged ·
Keith Haeusler wrote:Hi all,
This is my real life experience with taller top gear in a bug. In the early 90`s good mate had 68 bug, 2165cc,8.6:1 ida etc. Ran awesome. Never over heated oil or heads.
Changed to irs, stock L box, still good albeit lost a little bit of zippy-ness. Broke box, fitted .82 top with 3.88. Engine always ran hot in 4th gear and felt lazy.
Swap back to .93 top and problem went away.
I think the VW engineers knew what the score was.
Again, this is just what we found with this combo.
Regards, Keith
good example keith, thanx
so have we actually sorted anything about final gearing with aircooled engines from this mess?
i think Matt summed it up in his first post and Keiths post shows good back to back tests for his combo
i have plenty of thoughts as to why i've got away with my gearing,as per a couple of mentions from the Daves and Joel........ just trying to sort some time to write it up yet
did this one when Ct was choosing cams to show where this engine comes on song.......you can see it's well "in" @3000rpm and actually makes a shit load of tourque at 2750rpm which works well with the "5th" i have......another 100rpm less at 100km/h would see wide open throttle on anything steeper than a disabled wheelchair ramp.........now that would cause some heat (BTU's) in the heads all that fuel burning on climbs with no extra fan speed ❗
i hate this vid, sloppy changes blah blah, but easy to tell the car is not going to pull the 5th gear anywhere near as easy as the "4th"...........perhaps having the ability to go back to this 4th gear is my saving grace from long pounding climbs with W.O.T in what would normally be an "over geared" final drive ratio. i've pretty much only used the tall 5th for cruising as the gears before it provide ample fun and speed for a buzz........yes it does run a tad cooler, HOWEVER on long climbs i would have to say it raises in temps quicker than it did with the old gearbox.......hmmmmmmmmmm........time to shift down a gear, lucky there are 2 that will do cruising speed 😘
can't wait to get it on the road again, will refresh my memory and do some more vids.......hopefully run it at Wakefield to really test the theories 😎
matberry ·
dangerous wrote:Daimo found his ran cooler and got better economy.
And that was with a 0.82 fifth and 3.88.(way taller than the stock L-Bug 0.93)
I agree though that if you went too far, there may be issues.
I thought Daimos was going to be too tall, but he said it is great.
Mind you it has twice the stock power too.
Joel wrote:After going for a spin in Daimos old bug last year, I gotta say that tranny is geared to perfection but Like Dave said his engine has the torque to use it
expecting a stockish motor to run with the same setup would be kicking sqaure in the balls
How true are these comments.
After seeing Daimo's gearing you would think it's a little tall, but the engine has such good power delivery down low, it certainly gets away with it. A 1600 at 2800 rpm at 65mph would start to struggle because it's making less power at the lower rpm so more throttle is used and temps start to rise, and remember fan speed is less too.
Good thread
hellbugged ·
that's it Matt i truely believe my box would kill engines with anything less than my current one
......i'm a big believer in driving an engine to find it's personal REAL performance........maybe something for triebler to keep in mind for these subie boxes of his
yep good thread, hope it continues
Craig S ·
After getting a little off track I'm pleased that this thread is turning interesting again 😎
Would it be possible for someone to draw up a graph similar to Daimo's but using stock gear ratios (and tyre sizes) from an L Bug? At the moment I have no idea what rpm I'm doing at 110km/h, but I know it's damn noisy compared to 90km/h 😂
I remember there was an article last year(?) in the Club VeeDub magazine that gave the formuals for working out such things using tyre size, gear ratios and rpm.
Can anyone reproduce that?
It would also be possible if you swapped the x and y axis to overlay the above graph on a dyno graph, so that you can see where your engine power and torque is in relation to your gear ratios. Would that be of any use???
Thanks
Craig
hellbugged ·
Gwendolyns Master wrote:It would also be possible if you swapped the x and y axis to overlay the above graph on a dyno graph, so that you can see where your engine power and torque is in relation to your gear ratios. Would that be of any use???
transfer to graph paper after working the gearing calculator
Joel ·
Gwendolyns Master wrote:Would it be possible for someone to draw up a graph similar to Daimo's but using stock gear ratios (and tyre sizes) from an L Bug? At the moment I have no idea what rpm I'm doing at 110km/h, but I know it's damn noisy compared to 90km/h 😂
Hmmmm didnt i just use this photo in another thread on totally unrelated subject only a few mins ago 😂
Thing to remember is stock engines were designed to run flat bickey
Even 36 years later if your tinwares all in check and timing and carb are tuned right it will crank along at 4000rpm all day long,
trust me my poor little 1600 did it across the middle of Aus 10 years ago in 35c heat
My stock Lbug tranny at 110 is spinning 3200rpm
at 4000rpm its doing arouind 140 from memory which last time i checked wasnt the speed limit 😂
vlad01 ·
Phil74Camper wrote:Quite right Joel. To do it properly, you would carefully braze or weld the fan tabs so it can't come apart, then use the stock steel pulley and rev it as much as you want. Gene Berg used to sell stock welded fans. And you can use stock VW belts.
Power pulleys belong in the box with the billet distributor clamps, transparent distributor caps, chrome generator pulleys, brightly coloured coils, plastic heater hoses and all the other pretty bits that don't work as well as the stock VW parts.
Gene does still sell welded and balanced fans.
Power pulley do have their place. Idea behind them is to lower the ratio so that the fan doesn't over spin on high rpm engines and stall at something like 9000 rpm with the standard v-belt.
Don't place 100% faith in a welded fan, they still espload too,
just far less chance of it
matberry ·
Joel wrote:Thing to remember is stock engines were designed to run flat bickey
Even 36 years later if your tinwares all in check and timing and carb are tuned right it will crank along at 4000rpm all day long,
This is so true, straight from the owners manual...'maximum and cruising speed 75mph'...
I went even smaller than a power pulley on my 9000 rpm engine, definately not for the street.
Phil74Camper ·
Gwendolyns Master wrote:I remember there was an article last year(?) in the Club VeeDub magazine that gave the formuals for working out such things using tyre size, gear ratios and rpm. Can anyone reproduce that?
Craig
I'm glad you remembered that article - I wrote it! It was in the August '09 issue of Zeitschrift. You can download it as a PDF here:
where rpm is any engine rpm you like; circ is the rear tyre circumference; gear is the gear ratio, and final is the diff ratio.
For an L-Bug for example, with stock 165/70x15 tyres (1.923m circumference), and a 0.93 fourth and 3.875 diff, it would be doing 32.01 km/h per 1000 rpm in fourth, and 3436 rpm at 110 km/h.
Obviously you could use a spreadsheet to try heaps of different combinations, but no doubt there are websites around that do the same thing.
dangerous ·
Whenever these topics come up I always like to do some ratio combinations
for both the ultimate five and 4 speed Volksy type 1 trans.
You always must factor in your own tyre height.
A difference of one inch in diameter can make a HUGE difference on the highway.
If you have a little more torque than stock,
(as most people will, that go to the trouble of fitting a five speed into an air cooled),
I like this combination:
3.875 diff:
0.889 fifth
1.2174 fourth
1.6667 third
2.3571 second
3.7778 first
It can cruise at around 80km/h quietly at 3000 in 4th,
and not so tall as Daimos in 5th,
so the rev drop as you shift into 5th is better than stock.
If you want to stay with a 4-speed and have greater than stock torque,(say, with plus 2lt capacity and mild cam),
you can close up the ratios from the bottom:
3.875 diff
0.889 fourth
1.2174 third(early kombi)
1.857 second (aftermarket)
3.333 first.
This gives better than stock gaps between the gears,
and less cruising rpm.
If you prefer to use the stock 4th gear you can use the formulae, or Matt's spred sheet (below),
to make equivalent combinations with a little more rpm.
matberry ·
Not sure if this xl spreadsheet will work, but I'll try and post it, it's what I use (because I have it) and it does tyre size and gearbox ratios.
vlad01 ·
Joel wrote:Don't place 100% faith in a welded fan, they still espload too,
just far less chance of it
lol what was the fan rpm on that? 14000rpm 😂
Beware of so claimed "balanced fans" You can tell buy looking for welded in random pieces of metal through out the fan. they are counter weights. if no such modification are visible, Watch out these! They will wobble from harmonic vibration well before it hits it's potential rpm and may blow apart.
Joel ·
Nope, just one of the downsides of running a serp belt on a performance engine
Vbelts slip for a reason
General_Failure ·
Why are people having a hard time understanding low revs + more throttle is harder on a motor than higher revs and less throttle?
More throttle = bigger fire. lower revs it is sticking around longer heating everything up.
Less throttle = smaller fire. At higher revs heaps of little flames not sticking around as long are cooler.
Try an experiment. You need a cig lighter and a fire lighter.
Light the lighter. now wave your hand across it quickly. Easy right?
Now light the fire lighter. That flame's bigger and hotter, isn't it. Now try moving your hand over it slowly at the same height you did with the lighter.
Did you do it? I hope the nice nurse at A&E didn't laugh at you too much.
If you have your foot planted and aren't going any faster you are either in the wrong gear or breaking the speed limit 😉
matberry ·
General_Failure wrote:Why are people having a hard time understanding low revs + more throttle is harder on a motor than higher revs and less throttle?
More throttle = bigger fire. lower revs it is sticking around longer heating everything up.
Less throttle = smaller fire. At higher revs heaps of little flames not sticking around as long are cooler.
Try an experiment. You need a cig lighter and a fire lighter.
Light the lighter. now wave your hand across it quickly. Easy right?
Now light the fire lighter. That flame's bigger and hotter, isn't it. Now try moving your hand over it slowly at the same height you did with the lighter.
Did you do it? I hope the nice nurse at A&E didn't laugh at you too much.
If you have your foot planted and aren't going any faster you are either in the wrong gear or breaking the speed limit 😉
I see your point GF, but can't fully agree. Yes Wide Open Throttle makes more heat, but any engine should be able to take it.
VW states maximum and cruising speed, I know my transporter wbxr can drive sustained WOT for as long as necessary....and that has been known to be a long time 🙂, if the engines design couldn't withstand this, Volksies would have died long ago.
Gearing and cooling and engine performance and vehicle frontal area etc etc etc....all have a part to play.
Phil74Camper ·
Hi Tristan, your analogy is interesting but doesn't work in the real world.
The point of using a higher top gear (or a fifth gear) is to make the motor turn slower AT A GIVEN SPEED. In practical terms this can be the highway or mtorway speed limit - say 100 km/h.
Let's say your stock VW has to turn at 3500 rpm to maintain 100 km/h. It's designed to do that all day. Now you change the gearing so that it turns at (say) 3000 rpm at the same speed. To maintain 3000 rpm you are using LESS throttle, not more. The engine runs cooler and you use less fuel. You know that, in practice, you don't drive at full throttle at highway speeds. You accelerate to 100 km/h then you back off the throttle until you have just enough throttle to maintain 100 km/h. You only need more or even full throttle for climbing grades, whereas you might back off entirely doing downhill.
Now think of the reverse. Let's say you change the gearing to make it run at 4000 rpm at 100 km/h. You need more throttle to make it do that, so you burn more fuel and the engine runs hotter.
On average a taller gear makes the car run cooler and more economically - but only up to a point. You don't want to lug the engine, so you don't 'overgear' it - make top gear TOO tall. A VW 1600 develops its maximum torque at around 2,500 rpm, which in top gear is around 80 km/h. If you make it taller you move that maximum torque speed upwards, but at speeds below that you are potentially lugging the engine. That's a stock engine. This becomes a bigger problem with a performance engine, which has its maximum torque at higher rpms. So you have the potential there - a hi-po hi-rev engine and tall gearing - to lug the engine at highway speeds!
pete wood ·
Phil has a good point. I had an 091 4:56RnP fitted with a 0.77 4th for the EJ25 in my buggy. On the freeway it's great with the 31"s. Round town, it's awful. Can't make up my mind if I want 3rd or 4th all the time coz it lugs so bad. Put standard road tyres on and the car is transformed. The subaru is a torquey motor, but it's not designed to be driven at 1500rpm all day. It feels like a good aircooled. Smaller tyres and some revs and WOW what a difference, you can actually get the motor into it's preferred torque curve and power range. You can tell the diff in temp too. It runs hotter if it lugs at low revs all the time.
The big diff between this motor and ACVWs is, the cooling is not directly related to engine speed. ACVWs totally are. So to venture out of the most efficient fan range is for a given load is a serious concern.
Now if you really want to find all this totally irrelevant, from what I have heard, subaru motors in subaru cars (with a 5 speed) are set up to do round 3500rpm at 110kmh. Isn't that interesting. Pretty much the same as an ACVW... So what were we arguing about? 🙄
Smiley ·
Joel wrote:Thing to remember is stock engines were designed to run flat bickey
Even 36 years later if your tinwares all in check and timing and carb are tuned right it will crank along at 4000rpm all day long,
mattberry wrote:This is so true, straight from the owners manual...'maximum and cruising speed 75mph'...
I tried this on my way home from work this morning.
She could only manage 65MPH flat out 🤪
That's about 112km/h in my car 🙅
Might be time for a tune up.
That's not to say that it didn't run well like that. Sang along like a bird, if anything it got a little cooler, and didn't sound like pistons were jumping out through the block.
Smiley 😎
hellbugged ·
my na 02 subaru is very similar in rpm to my beetle pete
Except 4th as i wanted a close ratio box but with cruiser top....
vlad01 ·
General_Failure wrote:Why are people having a hard time understanding low revs + more throttle is harder on a motor than higher revs and less throttle?
More throttle = bigger fire. lower revs it is sticking around longer heating everything up.
Less throttle = smaller fire. At higher revs heaps of little flames not sticking around as long are cooler.
Try an experiment. You need a cig lighter and a fire lighter.
Light the lighter. now wave your hand across it quickly. Easy right?
Now light the fire lighter. That flame's bigger and hotter, isn't it. Now try moving your hand over it slowly at the same height you did with the lighter.
Did you do it? I hope the nice nurse at A&E didn't laugh at you too much.
If you have your foot planted and aren't going any faster you are either in the wrong gear or breaking the speed limit 😉
Spot on! the term is call "laboring the engine"
My crumpledore gets worse economy if rpm is less than 2000rpm. 5th gear is useless on this car unless you are over 95km/s on flat or down hill only. I can tell you laboring the engine is by far one of the worst things you can do besides running with no oil.
sander288 ·
Just a note on max speed is cruising speed, my 1300 on the gold coast freeway a few years back ran at full throttle for about 1 hour and it did not overheat or shirk at that speed.
The car also happily runs at 120kph on the F3 when it has to all day. At the end of last year in about November or so it was 40 + degrees in the hunter and high 30's in Sydney, I had to drive down from armidale in the bug. Flat out on the F3 in top gear it ran fine, but there was hyundais (who said get a good 5 speed...😂) and all other soughts of cars breaking down all over the shop with steam out of the bonnet! 🙅 😏
Joel ·
Smiley wrote:
Joel wrote:Thing to remember is stock engines were designed to run flat bickey
Even 36 years later if your tinwares all in check and timing and carb are tuned right it will crank along at 4000rpm all day long,
mattberry wrote:This is so true, straight from the owners manual...'maximum and cruising speed 75mph'...
I tried this on my way home from work this morning.
She could only manage 65MPH flat out 🤪
That's about 112km/h in my car 🙅
Might be time for a tune up.
That's not to say that it didn't run well like that. Sang along like a bird, if anything it got a little cooler, and didn't sound like pistons were jumping out through the block.
Smiley 😎
Bare in mind you car deviates quite dramatically to stock.
Big wide back tyres like yours place alot more load on the driveline not to mention the fact theyre taller than stock as well which is throwing off the gearing
Yes your car has less wieght with fibreglass kit and no rear bodywork but has extra weight in bigger tyre/wheels, front and rear bar work etc.
I imgaine aerodynamics would be affected somewhat on a baja too
A 5th gear in a vw is fine if you travel big KMs on dead flat motorway, but it would only take the slightest incline before the engine would start cracking a sweat
Like Daimo and others have said most modern 4 cylinder cars are doing 2800-3000rpm at 100km/h in 5th anyway
Its the big lazy 6s that can do less
matberry ·
I have a foreign car from Nth Darwin in our garage most of the time, the first SUV and it has a 2.0 efi waterpumper that has a 6000 rpm red line and is geared to nearly 3500rpm @ 100km/h. And it's a 5 speed too😂. I get into my wbxr after driving it and the diference in torque ... wow....the boxer admittingly is a 2.1 but pushing a much bigger bus, absolutely kills the rficer for torque.
Oh Ohh....more worms 😂
Smiley ·
Joel wrote:
Smiley wrote:
Joel wrote:Thing to remember is stock engines were designed to run flat bickey
Even 36 years later if your tinwares all in check and timing and carb are tuned right it will crank along at 4000rpm all day long,
mattberry wrote:This is so true, straight from the owners manual...'maximum and cruising speed 75mph'...
I tried this on my way home from work this morning.
She could only manage 65MPH flat out 🤪
That's about 112km/h in my car 🙅
Might be time for a tune up.
That's not to say that it didn't run well like that. Sang along like a bird, if anything it got a little cooler, and didn't sound like pistons were jumping out through the block.
Smiley 😎
Bare in mind you car deviates quite dramatically to stock.
Big wide back tyres like yours place alot more load on the driveline not to mention the fact theyre taller than stock as well which is throwing off the gearing
Yes your car has less wieght with fibreglass kit and no rear bodywork but has extra weight in bigger tyre/wheels, front and rear bar work etc.
I imgaine aerodynamics would be affected somewhat on a baja too
A 5th gear in a vw is fine if you travel big KMs on dead flat motorway, but it would only take the slightest incline before the engine would start cracking a sweat
Like Daimo and others have said most modern 4 cylinder cars are doing 2800-3000rpm at 100km/h in 5th anyway
Its the big lazy 6s that can do less
I tried again on the way to work this afternoon and got 75MPH 😂
Beats me what was going on the morning. I though it had more than 110km/h in it.
Smiley 😎
matberry ·
I wasn't recommending this behaviour 🤪🤪🤪
What Joel was saying is right, your car and almost everyone else's is no longer original or new, so I wouldn't recomend wot for sustained periods without components in top order and on a race track, speed limit is 110km/h if your lucky :😉:
Smiley ·
matberry wrote:I wasn't recommending this behaviour 🤪🤪🤪
What Joel was saying is right, your car and almost everyone else's is no longer original or new, so I wouldn't recomend wot for sustained periods without components in top order and on a race track, speed limit is 110km/h if your lucky :😉:
I don't normally drive her fast, just wanted to see what she had in her. The engine chugs along great down low and has plenty of pull for slow offroading. Which is what I prefer anyway.
Smiley 😎
vlad01 ·
Has anyone ever done 90? That is with an accurate speedo. 😉
Smiley ·
vlad01 wrote:Has anyone ever done 90? That is with an accurate speedo. 😉
My little maroon Semi-auto in my avatar has. When I bought the car it was supercharged, one day on the way home from work I wound it off the end of the speedo. That was a little scary, I didn't think the car had it in it.
Smiley 😎
matberry ·
vlad01 wrote:Has anyone ever done 90? That is with an accurate speedo. 😉
Pfffft 90
Aww c'mon oficer, it's only an old dak dak 😂
matberry ·
Even a mild well built 1600 will see gen speed..... 😂
vlad01 ·
Did in my old squareback going down a 15o hill with a good run up prior to going down it.
lol reving of its tits all the way😂
pete wood ·
I only ever got to about 80mph in my old beetle with a stock spec 1640, then the car felt like it was going to lift off the road... of course this was all closed road testing...🙄
Smiley ·
pete wood wrote:of course this was all closed road testing...🙄
I think that goes without saying.
I stop in at the test track on my way to work.
Smiley 😎
bajachris88 ·
Like dead roads behind acres of sugar cane fields 😂... those were the days....
Joel ·
Yup, my "private test track" used to regularly see me hitting 100mph 😂
bog stock 1600 too
having a supercharger and 0.82 4th was completely beside the point....🙄
On a serious note Ive managed 90mph from a couple of my superbugs, takes a good tail wind and run up but VWs top speed listing was always on the conservative side, even my mates 70 bug with a 1600sp managed 90mph
pete wood ·
that is seriously impressive. just as well they have all those "closed roads" up your way to test on. I should also say, the suspension on the car is a credit to you too. It looked very stable at that speed.
Joel ·
Doesnt take much to make a superbeetle stick like shit to a blanket
That was just some dodgy old camera phone footage
This one giving the subi some shit up windy mountain "race track" is much better quality
matberry ·
Gee thanks Joel. That was some real exciting stuff, those supers are real super, eh?👍👍👍😂
Joel ·
well I'll agree with the purist nazis they dont have the looks of the early bugs so they gotta make up for it in handling