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Old 7th April 2019, 09:56 PM
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Default Engine conversions for the D2

Thinking a few years in to the future, I’m thinking I’d lik to have a more potent engine transplanted in to the S8. I see lots of people posting threads about their engine conversions in golfs, 3series, A3’s etc so I’m assuming it’s possible in the D2 as well? I’m assuming money is the only limiting factor?

I wouldn’t want to spend 100’s of £1’000’s, but I’m not expecting it to cost less than £10k either. Assuming I can get the Quattro to be compatible what would be the easiest swap? Would I need the gearbox from that car too or would I could it be mated to the existing D2 S8 gearbox?

Engines I’ve condidered are;

D3 S8 V10
D4 S8 V8 TT
C5 RS6 V8 TT
B5 RS4 V6 TT
RS3 5 pot turbo

Has anyone considered this already or done a conversion already? Let me hear your thoughts guys.
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Old 7th April 2019, 10:05 PM
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Just get one of those, and leave your 8 with all the greatness intact
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Old 7th April 2019, 10:14 PM
MikkiJayne MikkiJayne is offline
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I have everything lined up for a V6 2.7TT swap (apart from time), really just for a laugh. It should make 500hp easily enough which, with a manual gearbox, should be quite good fun. With it being a V6, there is loads of space up front for an large intercooler. Cheapest swap of the low - I bought an entire 2.7TT Allroad for £700 so I think I'll be <£2K all in for the swap, then another £1-2K for tuning (mostly turbos) to get 500hp.

The C5 RS6 engine has been done but the biggest problem with that is intercoolers. There is no space up front with that so they have to go under the headlights. Lots of fabrication, and still only good for 500-600hp, but a bit explodey at that power output. Lots and lots of packaging issues getting all that hardware in the D2 engine bay which is considerably smaller than the C5 because the aluminium superstructure is much bulkier.
RS6 engines are very expensive for what they are because there are so few of them.

The V10 I am pretty sure won't fit but I'd love to have a crack at it. The drivetrain geometry of the D3 is quite different to the D2 to fit that monster lump in there. The D2 wouldn't have space for the radiator!

RS3 5-pot would be an awesome swap. 5-600hp, 5-cylinder classic Audi sound, inline engine so loads of space at the sides for turbo and manifolds. Length would still be an issue for an intercooler so it would need side mounts too. Still quite an expensive engine since it's quite new.

D4 4.0TT - now we're talking! Capable of stupid power (800+), nice and short, bolts up to the manual gearbox, charge-cooled so no issues with intercoolers. The big challenge here is electronics - it will take a lot of effort to make it run without the rest of the car, but people are working on it. Realistically I think you're looking at a £15K swap here though. The engines are still £8-10K for the S or RS versions. Its on my watch-list if ever Prestige get one in though

I'm assuming here you'd go manual for all of them btw since the 5HP24 is fragile enough with 360hp. It would just turn to shrapnel with 600. Theoretically you could keep it with the C5 RS6, but you'd probably get bored of a £3K gearbox rebuild with every engine service

Last edited by MikkiJayne; 7th April 2019 at 10:20 PM.
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Old 7th April 2019, 11:03 PM
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Quote:
Originally Posted by MikkiJayne View Post



RS3 5-pot would be an awesome swap. 5-600hp, 5-cylinder classic Audi sound, inline engine so loads of space at the sides for turbo and manifolds. Length would still be an issue for an intercooler so it would need side mounts too. Still quite an expensive engine since it's quite new.



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Is that not a transverse engine?...it is on Connor's new (to him) car
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Old 7th April 2019, 11:06 PM
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That’s interesting reading MJ. Appreciate the insight

I’ll be honest I was thinking the C5 RS5 swap would be easiest (although the one I least want) due to the base engines being so similar. I’m sort of glad you’ve mentioned it’s not straight forward as I’m looking to whittle down the list to 2 if I go ahead with the plan.

The D3 engine was always an over optimistic choice purely based on its size. It would sound nice but I’m not sure it would feel “that” much faster than the V8...I could be wrong as I’ve never driven one but the sensation from a big lump and turbo is like a mule kick from behind which the NA engines can not replicate.

The 5 pot Rs3 engine is transverly mounted - not sure if it could be adapted? That lump with s DSG would be immense but I don’t know if I could mentally get over having “just a 5 cylinder” engine in such a big car?

The D4 S8 engine is the one that excites me the most. How do you know it mates up to a manual gearbox? Has someone transferred one in to a car already you’ve seen?

The 2.7 TT engine from the B5 S4/RS4 C5 allroad is definately a close second just because of the bang per buck on them plus the switch to manual should be possible.

I’m getting excited just thinking about it.
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Old 8th April 2019, 08:00 AM
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Would the supercharged V6 fit, I wonder? They’re capable of silly power with a stage 2 tune and not much else. Common enough I would’ve thought to not be silly money. Would need to be a manual conversion I suspect, but might be feasible to build the 7 speed s-tronic into it? I suspect all of this will depend on being able to control the engine management with a stand-alone ECU and still have the rest of the modules working without flagging. Errors constantly
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Old 8th April 2019, 08:56 AM
MikkiJayne MikkiJayne is offline
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Quote:
Originally Posted by RICKY D View Post
I’ll be honest I was thinking the C5 RS5 swap would be easiest (although the one I least want) due to the base engines being so similar. I’m sort of glad you’ve mentioned it’s not straight forward as I’m looking to whittle down the list to 2 if I go ahead with the plan.
Physically the engine is almost identical but with a larger bellhousing. D2 engine mounts would fit it, but you'd need an adapter to get a manual gearbox on it, or keep the RS6 5HP24. Its all the surrounding infrastructure that would be such a pain. People don't believe me when I say the D2 has a smaller engine bay than a C5, but it really does. The D2 is longer in front of the engine, but narrower at the suspension towers and the firewall is further forward. I've worked on V8s in both platforms and there is so much more room around it in the C5 its silly considering the size of the car.

The RS6 engine consumes every inch of space in the C5 and so the couple of D2s which have been done have had serious packaging and heat management issues.

Quote:
Originally Posted by RICKY D View Post
The 5 pot Rs3 engine is transverly mounted - not sure if it could be adapted? That lump with s DSG would be immense but I don’t know if I could mentally get over having “just a 5 cylinder” engine in such a big car?
Yes, it is transverse, but thats just an issue of plumbing and fabrication. The biggest issue would be the oil pan and oil pump pickup, which would have to be adjusted to clear the subframe. You'd have minor issues round things like coolant flanges and manifolds, but its all just fabrication. The Americans swap transverse VR6s in to longitudinal S4s and deal with all of that stuff. It would have to go on a manual gearbox since the RS3 DSG clearly wouldn't work.

There are a couple of D2s with the original 5-pot turbo. They have the classic Audi quattro sound instead of V8 sound, but they lay down some pretty impressive 11s

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Originally Posted by RICKY D View Post
The D4 S8 engine is the one that excites me the most. How do you know it mates up to a manual gearbox? Has someone transferred one in to a car already you’ve seen?
Likewise 800+HP in a D2 would be epic! There is someone in the US swapping one in to a B4 Coupe. He's posted some interesting pics of the back of the engine - the bellhousing is identical to the RS4 manual gearbox and even the RS4 flywheel bolts up! VAG hate changing things when they work
Electronics obviously a challenge, but these days there are people who can solve that. The biggest issue I can see with the D2 is getting the turbo outlets to clear the firewall, because the D4 ones will go straight through the D2 heater! I think its likely it'll need a chunk of the firewall cutting out and re-shaping and then a pair of custom downpipes making to tuck in by the back of the exhaust.

Its popular for the S4 guys to put a single turbo in the V on the 2.7TT, with the exhaust down the back of the engine, but the D2 bay is so tight even that isn't possible. The D4 engine would need some brave pills and a TIG welder but I reckon its do-able.

Quote:
Originally Posted by RICKY D View Post
The 2.7 TT engine from the B5 S4/RS4 C5 allroad is definately a close second just because of the bang per buck on them plus the switch to manual should be possible.
Strangely no one ever seems to have completed one of these and I can't figure out why. There have been a couple started then scrapped. Its the same basic block as the D2's V6 so it should just bolt in. Some plumbing, some fabrication, a bit of same-generation electronics. How hard can it be? I guess I'll find out Mine was supposed to be done by now, but other work has thwarted that. I'm hoping to start it in the summer.

Quote:
Originally Posted by Adrian E View Post
Would the supercharged V6 fit, I wonder? They’re capable of silly power with a stage 2 tune and not much else. Common enough I would’ve thought to not be silly money. Would need to be a manual conversion I suspect, but might be feasible to build the 7 speed s-tronic into it? I suspect all of this will depend on being able to control the engine management with a stand-alone ECU and still have the rest of the modules working without flagging. Errors constantly
I thought about that one, but figured if you're going to deal with all the issues of getting modern electronics running in a D2 then you might as well just go big and use the 4.0TT instead. Theoretically the 3.0TFSI should be much the same swap, and yeah the engines are definitely cheaper. You might be able to do one of those for <£10K.

Definitely manual though. The architecture of the newer drivetrains is completely different to the D2 - the new stuff has the front axle line right behind the engine bellhousing with the torque converter actually past the driveshafts. Its a weird setup but it gets the engine 6" further back in the body. The D2 just couldn't accommodate that - you'd end up with the engine in the same place, but the output flanges 6" further forward which wouldn't work at all!
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Old 8th April 2019, 01:03 PM
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Default LS3 6.2 litre?

Have a read of this fantastic thread. I know its an American engine but it is a simple and very good engine. It will mate up to 01E with an adapter plate (that's what his car had) or you could go crazy and turn it into RWD with the stock Tremec transmission which would be fun too!
He used a LS1 engine but LS3 would be even better. Its the engine that was used in some Corvettes. Don't be tempted by the more racey LS7, its got some problems.

The two good things about those engines is they make monster torque at low revs, and can be built to put out 600hp. Also being push-rod the package is much smaller than the D2's V8. It only revs up to 6500 so not quite as high revving as D2 V8.

Also its not as heavy you save some weight.

https://www.motorgeek.com/viewtopic....01&hilit=judas

https://www.youtube.com/watch?v=E2ehWq9m8fA
was that a D2 in front


https://www.youtube.com/watch?v=iUnZU8TxO08

Last edited by Goran; 8th April 2019 at 01:47 PM.
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Old 8th April 2019, 01:29 PM
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Here is an example of a built LS3 bored to 6.8l, this one does rev to 7000.

https://katechengines.com/engines/?_...064.1554727693
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Old 8th April 2019, 03:27 PM
MikkiJayne MikkiJayne is offline
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By the time Project Judas self immolated, he'd poured so much cash and parts and time in to it that he might as well have just used a 4.0TT (had they existed at that time). It was an interesting project from an engineering perspective, but it just highlighted to me the many reasons for keeping with a family engine instead. The LS is considerably longer than the Audi V8 by the time it has all its accessories fitted. Haydn had to move the gearbox back several inches, and still had a lot of time in to finding the shortest possible accessory setup for the LS.
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