First off thanks for any help you may be able to give. I know this is only half thirdgen related but I don't know who else to ask. I have a 92 s10 blazer I just swapped a roller 305 from an 88 TA into. I want to keep the tbi for mileage reasons but I need to know what to do about the ecm. Right now I have only started to make sure it fires, which it does. I am almost certain the 4.3 ecm will run the 305 too lean, and it is showing symptoms of that right now. Is it possible to use the ecm from a full size truck w/305? Thanks again. josh

 

grab the computer from where the engine came...

 

What he said......I've helped quite a few guys out locally that did that same swap, believe it or not the 4.3 to 350 swap guys ran pretty decent with the 4.3 tune since the cylinder size is the same between a 4.3 and a 5.7. The 4.3 to 305 guys had tons of drivability problems. Either get a 350 chip for your ecm, or get the ecm that was in the T/A. You may have to swap a few wires to make everything work correctly, nothing major.