I have an 85 IROC with a 305 TPI. Had the trans rebuilt and mildly reworked with a 2200 stall convertor approx. 1 year ago. TV cable SEEMS to be adjusted properly. All shifts at normal speeds are correct. While traveling about 5-10 mph and putting the throttle to the floor, my 1-2 shift will not shift until 6800-7000 rpm's with very little wheel spin (most of the time). Afterwards, 2nd hits nice and hard and accelerates like a bat out of hell and all other upshifts are normal and real firm. I refuse to do this anymore because we all know that 5500 rpm's is the limit. I have no rev limiter or ignition box, just an HEI kit from Performance Distributors. No mods to the ECM. Any info is greatly appreciated and thanx in advance!!!

 

The only time I've seen one shift at "abnormally high" rpms was when it wasn't. The tach was bad. I don't know why it seems to happen in the lower gears and not all the time, unless you jerk/bounce/bump it harder than at the higher gear shifts. I'd put a second tach on it and compare it first to make sure it isn't an electrical problem before you go digging into the transmission/cable end of it.

 

irocrob

I have the same problem they tell me the line press is too high. I wont touch it until I can get my guage on it. I hear its better to have too much line pressure than not enough. Bottom line the TV cable is out of adjustment from what I was told.