ak,

nitrous works surprisingly well on diesels but getting the fuelling right on old mechanical injection engines is a bit of a pain. your audi should be fine though. to really get things going inject a bit of propane (lpg) along wiht the nitrous. there was a rover 400 diesel with nitrous / propane injection on the hi-power forum a while ago that was doing 6 second 0-60's and 14 second standing 1/4's which is stock supra / imprezza / mustang teritory. aparantly the guy seriously worried an ur quattro owner but was beaten on the twisties.

cheers

julian