You always say "we have a M5" Who is "we", your family? I am just confused, so I am asking.Maybe since we have one i can put this into a "real" perspective.
6 races ran
race 1: From a 30 mph roll, I had lenghts on him by 120
race 2: same
race 3: Around 50 - 60 mph (dont remember excatly) to 120 = wrx by a couple of lenghts
race 4 and race 5: from a dig = M5 still looking for traction while i was hitting 2nd. I shut it down at 3rd with 2 bus lenghts between us.
Race 6: another one from 2nd gear roll, I again pulled him.
If you care at all about the clutch in the M5 it is difficult to launch well and still be gental as to not to wear it out to quickly. The clutch doesnt last at all in that car. We have gone through quite a few. BMW has responeded to our inquiry about the weak stock clutch with "this is a natural failure point" this has been built into the drive line for one reason or another.
I actually had the clutch plate come off on me during a run down the 1/8 mile track. We had just had BMW service the car and install a new clutch. Had maybe only 1200 miles on it and i was on my 3rd pass i went to shift out of third and when i pushed in the clutch i heard and felt a loud slam. towed it to BMW and they said their tech didnt correctly install it. So we got another one and this time a flywheel too!
Now if you dont care to much and can replace the clutch when ever you want. Then obviously you will get better times.. We just didnt want to drive ours this hard.