Hey guys! I need your help on an issue I found recently on my 91 Z28. While driving normally, shifting is fine. However, when I slam on the gas while cruising, the car will downshift but gets stuck on the gear, thus reaching redline without shifting to the next gear. It does not do it all the time but it sucks when I go drag racing. I did some research and found out the throttle valve cable could be loose and could be adjusted quite easily. Any insights on that issue? Thanks in advance!

Transmission has been rebuilt 10K ago by the previous owner.
I have a BM Megashifter.

 

Sounds like it could be a governor that is sticking. If your TV cable is pulled tight at WOT it is set correctly. The governor and TV cable are really the only two inputs the valve body uses to determine shifts. Hope this helps. Which gear(s) does it do this in?

 

The problem seems to be on the third gear only. While cruising fourth gear, it will downshift to third and then redline. Same thing while drag racing, it will go from first to second to third but get stuck on third. Thanks for the precious info, I'll look into it!

 

Oh well that changes things. That is just how 700r4's are. They are suppose to never upshift into 4th under WOT or really anything above half. So if you are cruising at a very high speed in 4th and punch it, it will downshift and stay in 3rd no matter how fast you were going. There is a mod you can do by adding a set screw or two to the TV valve (I think) that basically plugs a hole and allows it to shift into 4th at any throttle. I can't believe you are topping out in third so much. With 3.73's at 3rd gear red line I would think that would put you at around 110-115 mph. Is this correct? Or is it slipping in 3rd and that's what makes it red line?

 

Some stock iroc will upshift to fourth at full throttle,but the 3-4 clutches are gone

 

Asked my mechanic yesterday who has a third gen trans am, told me the exact same thing I bought the car already modded but I don't know exactly what are the gears, before slamming on the gas I'm usually around 80mph, so I guess it would still be a stock 3.23....

Thanks!