Hello all,

I recently rebuilt a 350 vortec and installed it in my son's '89 Camaro. The engine has a ZZ4 cam, headers, a dual plane intake, and a Holley 600. The transmission is a 700r4 out of an '85 Camaro which I don't have much information about. Supposedly rebuilt, and working fine.

I reused the original throttle/TV bracket from the 305, and since the Vortec has a different intake, I modified the bracket to mount to the intake in the exact same position as it was originally on the 305. I have the TV linkage adapter on the carb that places the TV stud exactly where the factory wants it, so my throttle/ TV cable geometry is correct.

The trans shifts early and sloppy (takes too long) in all gears under part throttle. If you baby it, it seems ok, but shifting early. I put a pressure gauge on it, and checked it per the instructions in my factory manual:

TV hooked up - - - - - - TV unhooked, pulled tight (full pressure) @ 1000 rpm's
Park @ 1000 - - - 60 psi - - - - 120 psi
Reverse @ 1000 - 100 psi - - - -190 psi
Drive @ 1000 - - - 50 psi - - - -120 psi
1st @ 1000 - - - 120 psi - - - - 100 psi

Took it for a drive with the gauge attached - pressure sat at 60 psi the whole time. If I shifted manually, it might have seen 120 in 1st. I didn't drive it much since I don't want to toast it (that's if it isn't already). The TV cable is set up properly, and for grins, I moved it around, but it made no difference.

Thanks for reading, and I appreciate any help.

 

Your cable needs to be pulled tighter. This will make the trans shift later and a little firmer. 60psi is way too low.

 

Cable is set to run out of travel at wide open throttle. I tried tightening it more just to see if it would make a difference, but it didn't.

 

Did this cable work fine before with the old setup? If it did something has to be off with the geometry.

 

Yes, the cable worked fine. The old transmission had nearly 200,000 miles on it, so I thought I would give this rebuilt one a shot.

The new bracket, and cable connection on the carb is exactly the same as the original throttle body setup. When I pull on the TV cable by hand, it feels correct - at wide open throttle, it is tight. At idle, if I disconnect it, it pulls back about 3/8" or so from stud.

Thanks