I have an 82 Z28, 305 - TH350. When I floor it at about 30mph, the tranny downshifts, the engine rpm climbs to 5000 then it shifts, causing the car to hesitate and it won't keep accelerating. The tranny fluid is full, but my carb is not set up right. Could this problem be the carb like I am thinking, or is it the tranny???

 

Are you sure it's a T-350? None whatsoever of these cars came that way, you know; they came with 200s. There are no T-350s with the provision for the torque arm that's part of the rear suspension in these cars.

A carb cannot cause that. It's the trans. It should shift by 5000 RPMs. Those are not the finest example of American automotive engineering, to put it gently; they cause people alot of trouble when abused (just putting one behind a V8 could be considered abuse).

On the other hand, if the engine acts like it runs good for a few seconds and then falls on its face, it's probably a fuel supply issue... the fuel bowl in the carb is running out of fuel. clogged fuel filter, bad fuel pump, gunk built up in the pickup in the gas tank, etc.