Perttu doesn't own the V8 with S8 tiptronic transplant any more. I've met the new owner once in Vienna, a really lucky accident, actually. Anyways, what you've to know: The only known ABZ into V8 transplant is this one, whereas this is the S8 engine, but problems are the same.
If you can manage it to transplant the engine physically, you still have to deal with the problem that, and that's what the owner told me, the ABS sensors work in a different way, why you have to change the axes as well, which is hardly possible. Consequently, the pre-owner, maybe Perttu, has payd an incredible amount of money in order to get the auto-trans-ECU reprogrammed for the Audi V8 axes. That's required for the Tiptronic to work properly.
All this may be no problem if you want to out the ABZ in front of a manual gearbox, but this one has never been sold to UK, respectively has never been offered for RHD versions due to the reduced footspace. The only possible engine swap is, in my opinion, the Audi S8 340HP manual gearbox version.
But then, in turn, you can simply take the Audi S6+ engine, whch is practically identical. But, again, only on left hand driven Audi V8.
Best regards
Bastian
