I've been reading the board for a while now but have never posted...Anyway, I have a 1991 Z-28 350 with T-tops (pics to hopefully come soon) I recently bored the plenum and installed a new throttle body. After the install, I noticed the car seems to bog just slighty right before shifts...barely noticeable, except to me. For example, if I'm cruising along and my car generally shifts at 2,500 rpm, once the car hits around 2000 rpm it seems to hesitate or bog until the shift. It generally does it right before all my shifts too. Sometimes, it even seems like it shifts (exhaust notes change and such)but then the real shift will come only a couple hundred rpm later. I know all about the downfalls of the 700R4 but it really doesn't seem like a tranny problem seeing as how the shifts themselves are fine. I checked the tranny fluid and there is plenty and nothing is burnt at all...The car is in excellent condition with only 60,000 original miles on everything. I was planning on replacing the spark plugs, wires, and all that stuff but was just wondering if anybody else had ne ideas. Does anyone think it could be the new throttle body? Oh yea, it doesn't bog at all at WOT or even 3/4 throttle

 

neone got ne ideas?

 

Try resetting the detent shift cable. The new throttle body may have the actuator lever in a slightly different location as opposed to the stock one. If you changed nothing but the throttle body, that would seem the most logical starting point. Also, how big did you go on the TB? If your engine is stock and you put a 58mm TB on, that could also possibly account for the surge feel.

 

I got the 52 mm BBK throttle body...I'll try what u suggested...thanks