This isn't my car (I wish it was) - it was owned by Sean Wagner, and was a 1990 model, widebody, full engine build, running twin TD05-18G turbos. When he went in for the pulls, his first pull was at 24psi with no spray and netted about 586whp. This pull, he turned the boost down to 20psi, ran a 60-shot into the engine, hit the N20 intercooler spray, and landed with 744whp and 700wtq. The video quality is poor, but it sounds great and gives a really good show of the IC spray in action.

I know it's not an Audi, but I love this Z

The video: http://www.youtube.com/watch?v=1mnZNo7KF-U

The chart: