Quote:
Originally Posted by RICKY D
Actually as I’m typing I realise the engine already exists....well sort of  the v8 in the B7 RS4. |
They work pretty well with the intake de-coked and de-flapped. I know of one being transplanted which made 420hp on the dyno after that work so exactly on spec.
The electronics though
Taken out of their native home, the two ECUs are properly grumpy about missing all the modules! Its much the same challenge as using a 4.0T or 3.0T tbh, for only another 60hp. Not sure if it would be worth it? We'll probably see in a couple of weeks if this transplant behaves itself.
Re tuning the 4.2, I'm sure there is some scope for porting the heads, making better headers, high flow cats, etc. Not sure how much more you could get from cams since the S8 already has a more aggressive profile. Might be worth sending some to a cam specialist like Newman to see what they think.
Throttle bodies on it would be quite spectacular too, albeit at the expense of torque. There's the option of a supercharger too, which would probably put it in the same range as the RS4 but with less hassle. There was one advertised on Audiworld a few weeks ago.