Well, folks use Garrett GT turbos, and Garrett/KKK hybrids, and I've
even seen a Nissan turbo on one car.
Goto Audiworld, and go to the original S-car forum. Do a forum search
on turbo upgrade options, and you'll have a TON of info. Become a
member, say "Howdy" to the UrS crowd (they're pretty good people,
mostly), and then ask questions. (Do the forum search first, so that
you don't get five replies of "STFA" - "search the, uhhh, forum
alt.autos.audi seems to be much more "Honda-ified" in recent years,
with much less technical expertise being passed around - Audiworld gets
much more technical traffic.
Good luck, and see you on the UrS forum.
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