JimC

jimkaray is right, I did break the pinion on my 7.5. I had a set of DR's on the car, had the Tlok installed, 3.73 gears (Richmond which supposedly were unbreakable although they whined), and a LPW girdle to strengthen the rear end.

But I broke it before I even had a chance to launch on the nitrous. The grip of the DR's at the track, launching at 1800 rpm on the automatic, was too much for the 7.5. I rebuilt it (second mistake, should have replaced it with an 8.8 to begin with and should have replaced it rather than rebuild it a second time - was cheaper to go with the 8.8) and the 75 shot of nitrous hit the driveline hard, but it was a lot of fun.

If you don't have a window switch get one. I tried without and found that although the Zex system learned WOT it would read it very low in the RPM's. I was lining up at Grand Bend one night, brought the RPM's up to stage and only got to 1500 when the system read me as WOT and fired off. After that I put a window switch in and set it to not allow the system to fire until the window switch saw me pass 2400 RPM.