Hi i have a 91 gmc sierra, just put a rebuilt 350 TBI in it and its mated to a 700r4 tranny. ive replaced the fuel filter, injectors, rebuilt the fuel pressure regulator in it and cleaned the **** out the the throttle body. especially when in overdrive it has a bog when rolling into the throttle, but today i was just in drive and it constantly bogged when shifting from first to second....what the hell is going on? torque converter? servo? im baffled and need to drive 12 hours next week please help

Have you changed your fuel filter lately?
Also, TBI systems put much greater stress on the main injector, and sometimes they stop reacting quickly enough to provide sufficient quantity of fuel at higher RPM under load.
Start by replacing your fuel filter, changing ALL FUEL IN THE SYSTEM (to rule out fuel contaminant issues, especially if you've been using ethanol blends), and check the fuel pickup in the tank to be sure it isn't clogged or obstructed.
When all else is ruled out, try replacing the main injector.

They don't adjust. They go in the tbi and seat to the bottom if they are leaking you need to change the o rings on them.

if your carb is a tbi (throttle body injector) then the carb is clogged

Could be fuel filter,air filter,dirty throttle body.

try the temp sensor by the thermostat housing,make sure its not broken when you unplug it,ohm sensor itself when warmed up,and when cold

Sounds like a simple case of bad, damaged, or disconnected Engine Coolant Temperature (ECT) sensor to me.

Also review this article:
What Else Could Be Wrong?

I did, but I had to exchange the drive shaft b/c the length was wrong. the R4 has OD, and the 350 does not, making the 350 shorter. It's no a great idea. I was unhappy with the 3 speed 350 because of very poor gas mileage, so I went back to the r4. I had a bit of an issue with the speedo cable and the tranny crossmember mount too. It's not really worth it, but yes, you can do it, but it's going to take fab work, and after my own ordeal, I'd not really suggest it. I was just trying to save a few bucks, and got myself into a world of hurt. lol you live , you learn. Unfortunately Fixya did not exist back then.

there's a filter on each injector. once you take a top of the throttle body off and pry each injector out, you'll see it.

It will mate to the engine, but the turbo 350 is shorter then the 700R4 and your going to loose the lower first gear ratio in the 700R4 and the OD that the Turbo 350 don't have. It can be done, but your going to have to relocate the transmission cross member and have a longer drive shaft made.

Good luck.

If your check engine light is on have it checked out have some one extract the code. You may also want to check out the throttle position sensor.