Purely in the interest of science *cough* I raced my friends mk3 valver in my 1.8T. Both cars modded with full stainless steel systems but that's it. Here's what happened..
0-60 he pulled on me, half a car length ahead by 60.
60-80 I started to creep up
By 95 we were level pegging
Continued to pull on him and was maybe a full car length ahead by 120 before shutting down (ran out of road)
Not sure if that'll settle an argument or cause one

we all love our own cars !