sgtredsox

I recently replaced the 305 in my '85 chevy LWB truck. Motor came from a 92 Camaro. Now the truck has NO power (can't even get out of its own way!), occassionally backfires when the secondaries kick in, and diesels like crazy until the bowls run dry. I have tried timing it several times with a light, but the "book" timing barely keeps it running at idle. A friend said my Computer is crapped out and that there is a way to bypass (read=Jury-rig) the computer tofix my problem.Does this sound right? if so...how do you bypass it?
Any help is appreciated.