KLeech

you can get the transgo kit off summit and i know for sure its either 80 or 90 bucks.

sonicx

Well idk prob so though aint doubt that. I picked mine up couple years back but i know theres 2 different ones TRANSgo made for the stang. I got the more expensive of the two.

smythge

I would change the 1-2 shift point. With stock gears your motor revs about 1,000 RPM per second it takes about 1 sec for the 1-2 shift that's why you set the shift point 1,000 RPMs below where you want it to shift. Now if you change to 4.10 gears you motor is spinning up faster than the 1,000 rpms per second, so what happens you hit the rev-limiter, you need to experiment and drop the shift point.

If you don't think it's the shift points another common problem for 1-2 shift problems is the intermediate one way clutch. A failing one way clutch will cause late 1-2 shifts often hitting the rev-limiter here is some information on the problem http://tccoa.com/articles/tranny/tra...on/page4.shtml

I have a automatic with a supercharger and 4.10s and I just put a transgo shift kit in today for this exact problem, it shifts fast but I still had to back off my 1-2 shift point, I am currently at 4,750 RPMS. I am going to have to play with shift points to find the sweet spot.