What year Mustang is it? Is it 5spd or auto? If it is a 99 or newer 5spd, he will take you in the 1/4 no doubt, unless he is a just horrible driver. If he is auto, it would be close in the 1/4. The older 4.6 and 5.0 Mustangs are easy to make fast, but if stock can be beaten rather easily.

On the road course its a whole different ballgame. Depending on the course, its a toss-up...if I recall that SCC article correctly, the Mustang won in one configuration and the R won in the other.

The thing is....he has a high torque RWD V8 engined car....he *should* be faster in the 1/4...physics dictate he has the advantage. What a lot of people dont understand is that in the quarter mile, the ITR is totally out of its element. You are putting your car's weakest trait against the Mustangs strongest trait. Sure, go to the strip and possibly get beaten by a bit....then invite him to the next autocross and hand him his ass on a platter.