I have a Cobb Stage II STI and I have a friend who just got a 5-speed Mustang GT a few weeks ago. I've been dieing to race him. Well we raced the other day. We did 3 runs from a stop.
1. I got a perfect launch and he said he had a lot of wheelspin (I couldn't see him ) and I imediatedly jumped 1.5 car lengths and at about 100 - 110 when we shut down I was about 2 - 2.5 carlengths ahead.
2. I bogged, he got a jump for a second and then I pulled 1 car length once I hit the top of second and he stayed about a same distance up untill 100 when we shut down.
3. I launched hard, too hard. I quickly slipped/dropped the clutch at 5k- 5.5k I spun all 4 wheels and it was revving at 6500 my tires were still spinning, in fact I was sliding into my friends lane Once I got moving, I was only about 1 - 1.5 carlengths at 100.
His car is bone stock with obout 2k miles, and I had just completed the install of the final part of my stage II setup (the catback). And I was getting 18.5 pounds of boost the day before (pre catback install) and I was only getting around 16.5 - 17 on that day. I'm assuming my ECU was relearning becuase now I'm getting 18.5 again. I'm not trying to make excuses, but I thought I would have beaten him by a larger margin.