a friend has a 1.3 shell with mk3 vr6 running gear and a silly fast 16v engine. that is a really nice car to drive. he has no idea what has been done to the engine but it has a lot of poke.
With that 1.8 16v, You could fit diesel pistons IIRC to increase the stroke length to almost 2L which revved lower but gave good torque and less top end speed. I had a cam but it idled like crap and was only any good with silly revs. The valves tend to get bent too if you are maxxing it out for long periods (where legal
). Happened in one of mine.
The 3.7v8 that went into the Audi A8 was basically two of the 16v engines joined together.
I've always wanted the S8 that someone else has shown in this thread, but I think you are talking mid-teens to the gallon and group 20 insurance. And apparently the 4wd has to be aligned regularly and not all Audi stealers have the kit... Not financially sensible for me at the mo.
Shame, as I reckon that S8, original RS4 and orignal S3 are best designs Audi have done - the new Audi saloons, really, I struggle to tell apart. Do they need that many models and variants?