Engine swap 2.7tt to 1.8t

[HibiscusS4]

My S4 has developed a bit af a fault that I am a bit worried about. It also has 142k and a very high clutch pedal. I have been considering the options of taking the 2.7 out to swap in a 1.8T I am on a trade policy which allows engine swaps so thats no issue and I realise it will devalue the car slightly if I choose to sell.

My questions are is it worth it? For the 1.8 swap I guess I would need the whole car on the same year but these can be had for cheap in FWD form. Are the looms plug and play? I know I can use VACOM to sort the immobiliser and reprogram my tacho to 4 cylinder but would the DIS then all work and cruise control ect.

Is the 1.8T MPG much better or not worth thinking about (I get 26 on the DIS for the mix of driving I do)? Can I then fit a big turbo to the 1.8 and get back to 265ish BHP in the future easily enough? I know swapping the turbo will be easier on the 4 pot.

 

[colicabcadam]

just understand that no one would buy it when you come to sell it, people buy s4's for the v6 tt !!

cant you buy a second hand v6 motor ?

 

[adamss24]

Sell yours and buy a 1.8TQS then be done with it ! Or you could break it and put the money towards the new car...

 

[HibiscusS4]

As a keeper though its about as cost effective as buying a 1.8TQS and then fitting an 01E and big brakes. I have been watching a few V6's and they seem to go for good money in unknown condition. The lure of the 1.8 is being able to drive the car before taking the engine out.

A whole driving 1.8T is cheaper than an unknown condition 2.7TT engine without turbo's!

 

[Prawn]

Fu<k it! Dare to be different!

Ditch the heavy V6 and bang a 20vt in there with a decent turbo.

A friend of mine has a MINT noggy B5 S4 shell that's getting a 2.3 4 pot Saab engine with a Holset turbo, so a 20vt S4 seems tame by comparison

 

[aragorn]

I did this for my track car, albeit using a bare S4 shell.

I bought a 1.8T FWD for £250, removed the engine/harness/etc, scrapped the shell for £100 and sold the wheels for £50, and various other bits (central locking, steering wheel) for making the engine almost free.

The engine will more or less bolt in. You'll need to hack the exhaust about a bit though (or use a 1.8TQS system), and the PAS pipes will need swapped.

 

[HibiscusS4]

So I dont need to change the lock carrier and subframe? I have been Googling about and all I can find is people swapping a 2.7 IN to other models and they all say you need a V6 lock carrier and subframe.

Does the 1.8 sit in the same place then, I was under the impression the S4 V6 sat further forward to get all the turbos in behind. Exhaust is not a problem, I was looking at making a custom front section to bolt up to the standard rear box, I have a pipe bender and a welder.

I will be investigating the fault this weekend, going to Audi for a new cam cover gasket to fix the leak, while its off I'll inspect the cams as thats where the noise is coming from but the high clutch and time bomb turbos also concern me.

EDIT:- probably not on a track car but would the AC be a case of just changing the pipes from the 1.8 to the 2.7, would Climate control then function correctly?

 

[aragorn]

yeh the gearbox sits in the same place on both cars. 1.8T will drop right in.

It'll also fit fine with the V6 subframe afaik, the front panel needs changed as the snub mount arrangement is different and the 1.8T has a metal boost pipe along the bottom, but you'll have those from the donor car as well as the radiator.

You'll need 1.8T AC pipes and dryer, but that should all just work, the climate control doesnt know or care what engine is fitted. Again, if your donor has AC then perfect to swap it over.

 

[shaz8389]

Call me crazy but what about just fixing the S4 clutch?

 

[HibiscusS4]

Its an engine out job and I might as well do the turbos while I'm there so its going to hit the wallet big time. There is still the chance the 2.7 is goosed aswell.

 

[Chriscooke]

The 1.8t is ok but it's pretty gutless in standard form tbh. I'd imagine that you'd soon get bored of it compared to the s4 lump.

 

[aragorn]

True enough, but the problem with the S4 engine is everythings twice as expensive and four times as awkward.

Even little things like the rocker cover gaskets he mentions is required is about 60quid for the pair, plus he'll need the half moon seal and tensioner gasket twice as well which is another 30-40quid. Then you have to dismantle half the engine bay to fit them.

They're certainly not cheap cars to run when compared with a 1.8T.

 

[sportstractor]

Lol I always fancied an s4 as well. After hearing that, if i got one, it would have to be the v8.

Surely when you add it up, getting a decent low mileage 1.8t, all the TQS ancillarys, the extra work and how much it would devalue your car, you would be better off fixing or replacing the 2.7?

You sound quite capable, so can't be that bad if you do the work yourself? I only really back this side of it because i had an 8l s3 running around 285, and it was quick but not mind blowing,". But that was the max I could get from the K04 (and wasn't exactly cheap to get to that stage) coupled up with a heavier car it's not going to be outstanding, and bt conversions arn't exactly cheap when you factor in rods, custom manifolds, mapping, bigger injectors plus all the little things that really do add up.

My brother has a standard a4 avant 1.8tqs sline, and it's literally the most boring gutless car iv ever driven, I actually prefer my sportback

 

[HibiscusS4]

True enough, but the problem with the S4 engine is everythings twice as expensive and four times as awkward.

Even little things like the rocker cover gaskets he mentions is required is about 60quid for the pair, plus he'll need the half moon seal and tensioner gasket twice as well which is another 30-40quid. Then you have to dismantle half the engine bay to fit them.

They're certainly not cheap cars to run when compared with a 1.8T.

Gutted, I bought the gasket today (just one) and it cost me over £40, I didt realise you needed other parts!

 

[aragorn]

Yeh theres a small rubber half moon underneath the cam tensioner which often leaks, and the tensioner gasket itself often leaks too.

You need to remove the inlet camshaft and compress the chain tensioner to change it. You need a special tool to compress the chain tensioner, but they're only a few quid on ebay.

 

[aragorn]

an FYI...

I've been sat here this afternoon poring over wiring diagrams, as i've just realised the connectors between the engine loom and car loom are different between the S4 and the 1.8T harness. Not insurmountable, once i've identified the wires i'll solder the S4 connectors onto the AEB engine harness and it'll plug right in, but not as plug and play as i'd thought!