CTWG60's 24VRT - It will be a long slow (non-existant) build

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I don't know the engine code tbh, I've never looked for it or thought about it. I just knew I wanted a 2.8 and one came up for a good price. It's actually out of Stealth's old Bora, which I drove before it came out and it felt good to me

Good info there on the cam mapping etc, you've been doing some research too! Please pass on anything you find as I need to know it as well

It's funny, I see Jefnes on the Vortex thread (he's king nerd of C2 Motorsports) said the cam timing isn't full advance or full retard, but infinitely variable. But it was C2 who told me the early 2.8s have exactly that, full on, or full off

So we need to find out for ourselves and get the definitive answers!!

Either way, both Emerald and DTA mappers have found big torque gains from c0cking about with the inlet cam

Sounds like something for Wayne at Chipwizards to get excited about. I know Wayne gets a bit of bad press for not answering his phone but if you get him on a one-to-one there's nothing this guy doesn't know. He was talking about wierd a new motor, runs on diesel that is stored in a compressed liquid and as it's pumped to the engine it has it's state changed to a gas, he was working on it with some new Nira diesel engine management system.

Anyway what I'm trying to say is, Wayne would get to the bottom of this stuff or already has. Next time I'm down there I'll pop in and have a chat with him.

This thread will contain all my research so feel free to chuck some links in if you have any. If these things are controlled by a some sort of PWM solenoid for oil it should be fairly simple to control, the difficulty as you say will be cocking around to find out what works and what doesn't. I guess the best way would be to just to have the solenoids set up against rpm with the injectors batch firing then move on to sequential mapping of the injectors and the firing angle.

If you check ETKA the early mk4 golf 1999 heads (AQP) have a camshaft adjuster under "camshafts and valves" ill. 109-45

Later BDE 2002 have the oil pwm system just like the the R32, slightly different part codes though. Under "timing chain, guide rail" ill. 109-90

IIRC the early VW 24v VVT is just on the exhaust cam, and is acheived by pushing a guide between the two cam sprockets upwards, thus pulling the exhast timing forward. It's interesting as VVT is normally on the inlet cam alone rather than exhaust. (obviously the newer VVT is in both)

Can't really find much on the earlier 24v on/off VVT.

ctwg60 wrote:If you check ETKA the early mk4 golf 1999 heads (AQP) have a camshaft adjuster under "camshafts and valves" ill. 109-45

Later BDE 2002 have the oil pwm system just like the the R32, slightly different part codes though. Under "timing chain, guide rail" ill. 109-90

OK, this correlates with what C2 were saying then.

From the horses mouth.....

C2 Motorsports UK wrote:THere are a few versions of the 24v engine.

The 1st of which is coded either AUE or AQP. This engine has a coil pack rather than coil on plug. It also doesnt have true variable cam control - The inlet cam has 2 positions. This uses a Bosch ME7.1 ECU

The next engine is the BDE (3.2 is BFH.) This engine is coil on plug and has true variable cam control.This uses a Bosch ME7.1.1 ECU

The next one is the 3,2 (coded BUB) returnless fuel system engine, This is the MK5 R32 and Audi 3.2 engine. This engine uses a Bosch ME7.1.1 ECU, although it isnt compatible with the earlier ME7.1.1 ECU.

The best ~allround engine (for a conversion) I think is the BDE/BFH.

C2 Motorsports UK wrote: The AUE has a different head to the BDE.

The mechanical difference in the cam control is: different cams, the timing chain setup, and the actuators.

C2 Motorsports UK wrote:The AUE is more basic than the BDE. The cam control on the AUE is the same method as used on the 20v engines, The BDE cam timing is variable, ie lets say that all the way advanced is 0 and all the way retarded is 10, with this engine you can set the cam timing to be anywhere from 0 to 10. With the AUE the control is either 0 or 10.

I think I have an AUE, which is the most basic, but it'll be run with a standalone so doesn't matter. I can always throw on an R32 or BDE head if I want true variable cam phasing

Stu, there would be no gain in VVT'ing the exhaust cam only. VW introduced the VVT (inlet) to boost bottom end and midrange torque
The later engines got full control on both cams more for emissions than anything else.

Cool, nice info. I think you can run the BDE engine and just ignore the VVT and it will still run, so that's the fail safe anyway.

I did have a discussion with one of the guys at Pi about the cam timing, and he said something simiar, but I can't remember now which side the top chain is 'tight' and which side is loose. I'm fairly sure the tight side is the inlet side i.e. the side that doesn't have the tensioner pad on it. The tensioner pad allows for the flexibility to pull the exhaust cam forward. I suppose if you have the engine setup in such a way that pulling the timing on the exhaust actually just increases overlap and also that it closes earlier will allow you to increase the amount of burnt/used gases in the cylinder and thus improve dynamic EGR of the system and thus reduce the emissions. I suspect that is why it is there rather than any performance gains. The variable intake provides the added low end grunt.

kevhaywire wrote:

ctwg60 wrote:If you check ETKA the early mk4 golf 1999 heads (AQP) have a camshaft adjuster under "camshafts and valves" ill. 109-45

Later BDE 2002 have the oil pwm system just like the the R32, slightly different part codes though. Under "timing chain, guide rail" ill. 109-90

OK, this correlates with what C2 were saying then.

From the horses mouth.....

C2 Motorsports UK wrote:THere are a few versions of the 24v engine.

The 1st of which is coded either AUE or AQP. This engine has a coil pack rather than coil on plug. It also doesnt have true variable cam control - The inlet cam has 2 positions. This uses a Bosch ME7.1 ECU

The next engine is the BDE (3.2 is BFH.) This engine is coil on plug and has true variable cam control.This uses a Bosch ME7.1.1 ECU

The next one is the 3,2 (coded BUB) returnless fuel system engine, This is the MK5 R32 and Audi 3.2 engine. This engine uses a Bosch ME7.1.1 ECU, although it isnt compatible with the earlier ME7.1.1 ECU.

The best ~allround engine (for a conversion) I think is the BDE/BFH.

C2 Motorsports UK wrote: The AUE has a different head to the BDE.

The mechanical difference in the cam control is: different cams, the timing chain setup, and the actuators.

C2 Motorsports UK wrote:The AUE is more basic than the BDE. The cam control on the AUE is the same method as used on the 20v engines, The BDE cam timing is variable, ie lets say that all the way advanced is 0 and all the way retarded is 10, with this engine you can set the cam timing to be anywhere from 0 to 10. With the AUE the control is either 0 or 10.

I think I have an AUE, which is the most basic, but it'll be run with a standalone so doesn't matter. I can always throw on an R32 or BDE head if I want true variable cam phasing

Stu, there would be no gain in VVT'ing the exhaust cam only. VW introduced the VVT (inlet) to boost bottom end and midrange torque
The later engines got full control on both cams more for emissions than anything else.

Have you got a link for these quotes?

kevhaywire wrote:Mr John - No mate, you'll no doubt be glad to hear

I have stripped my 130k 2.8 24V motor down and other than the usual guide rail snappages (the plastic goes brittle with age) all looks in great shape :salute:

Mr PeteGriff - That shot is motoring porn. V8, individual throttle bodies, a big chain.... you knew that would have me nursing a semi didn't you? You git. I'm at work aswell....

That seals the deal I think I'm going early 2.8!

/\ Seems to back up what I've heard. 500whp and the block can crack / flex / warp. Further evidence can possibly be found from Stealth's R32 turbo. That was making well over 600whp and the oil pump apparently let go and the engine bought it. Could the pump gearing have moved out of mesh slightly due to block flex? Hmmmm....

2.8 all the way for me.

Just spent the last 1/2 hour thinkinbg about the early VVT. The chain setup is different between the 4 pots and VR, as we know, so thinking that the flywheel turns clockwiseanti-clockwise, thus the intermediate sprocket also turns clockwiseanti-clockwise, the top chain goes from the intermediate shaft through a guide-rail to the inlet sprocket then over the adjustable guide between the cam sprockets then over the exhaust sprocket, down over the tensioner back to the intermediate sprocket the top chain is pulled tight on the inlet side. With that in mind surely the exhaust cam's timing is what is adjusted? The flexibility is provided by the tensioner??

I can't find any details on the function of the early vvt system but it is the intake timing that is changed.

So when sourcing a 24v vr engine what else is prudent to get at the same time, are all 24v engine DBW?

ctwg60 wrote: can't find any details on the function of the early vvt system but it is the intake timing that is changed.

Been searching found a couple of citations.....

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In my earlier post I said the flywheel turned clockwise...I was obviously wrong. I which case it confirms that the inlet side of the top chain will be tight, and thus, it's not possible to adjust the timing, via the method VW used on the early 24v, on the inlet cam. It must be the exhaust.

Good info! I think I stand corrected. Cheers Stu!

mrbeige wrote:IIRC the early VW 24v VVT is just on the exhaust cam, and is acheived by pushing a guide between the two cam sprockets upwards, thus pulling the exhast timing forward. It's interesting as VVT is normally on the inlet cam alone rather than exhaust. (obviously the newer VVT is in both)

I'm confused

The 24v doesn't have a seperate "exhaust" cam. It has front and rear cams just like the 12V, i.e. a pair of split duration cams and rockers. The rear cam opens the intake valves on the front bank, and the exhaust valves on the rear bank, and vice versa with the front cam.

Maybe it's Friday and I'm knackered, but how can you alter the timing on one cam / bank and not the other when they are mechanically tied together?

I need to get my head on the bench this weekend and figure it out.

I'll take some pics and post them up!

What you say is true of the 20V because it has seperate cams for exhaust and intake.

THAT, Mr Wire, is a bloody good point!! But, then why would you have timing adjustment on just one cam, whether it be the front or the rear cam? Does the 24v not have the same cam arrangement as the R32 then, with a inlet and exhaust cam separate? And then, how do the later 2.8 24vs have timing adjustment on both cams?

Ha! WTF. err. Strating to think the early engine didn't have VVT and the later had... no I don't get it. Kev will have to investigate!

mrbeige wrote:THAT, Mr Wire, is a bloody good point!! But, then why would you have timing adjustment on just one cam, whether it be the front or the rear cam? Does the 24v not have the same cam arrangement as the R32 then, with a inlet and exhaust cam separate? And then, how do the later 2.8 24vs have timing adjustment on both cams?

I know, it's weird isn't it? The 24V must use some kind of special sprockets....I'll know more very soon

The 2.8, 3.2 and 3.6 24V engines all work in exactly the same way. They're all twin cam with each cam having both intake and exhaust duties on their opposing bank. It was a packaging masterpeice by Cosworth, and still is imo

Maybe the Cams are tubular in that one cam runs inside the other allowing the intake and exhaust to be changed individually?! No that's bollox!

kevhaywire wrote:The 2.8, 3.2 and 3.6 24V engines all work in exactly the same way. They're all twin cam with each cam having both intake and exhaust duties on their opposing bank. It was a packaging masterpeice by Cosworth, and still is imo

I dunno, I think having looked at the relative angle of all intake valves in the front and rear bank and indeed the all exhaust valves too, I reckon there is indeed an intake cam and exhaust cam separately. See below...

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You can see the 'rockers' bridging from one side to the other in this piccie...

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Well fun me I think you're right mate.....

I didn't get round to checking mine over the weekend, too many jobs to do round the house and the missus wanted her christmas lights putting up, LOL!

My car's going into the body shop this week, so that'll give me some time to fiddle about with the 24V

kevhaywire wrote:Well fun me I think you're right mate.....

I didn't get round to checking mine over the weekend, too many jobs to do round the house and the missus wanted her christmas lights putting up, LOL!

My car's going into the body shop this week, so that'll give me some time to fiddle about with the 24V

I'm gutted you didn't get chance to look at your 24v, I was eagerly waiting for your return this morning to confirm or deny the above pics

Is that one above an early or late? I'm just looking at the oil ways in those cam ends which the sprockets slot onto.... I think that is the key to it mate. That is what I want to try and figure out

Looks like that one was over fuelling a bit. What car's it from? I guess VW run the VR engines slightly rich to keep running temps in check....hence why R32s struggle to exceed 25mpg?

Compare that to a Chevy LS1 6.7 Litre V8, with 2 seperate banks, which can return 30mpg!!