I have a 2002 4.8 automatic rado and want to drop a 5.3 or prefferably a ls1 into it. i pull a trailer 30% of the time and the other 70% i just wish it had more power. I have either motor lined up and know all the connections should be the same but will the pcm be able to compensate? Do i have to calabrate the pcm? If anyone has done this let me know, ive searched and knowone seems to know. also if the pcm needs tuning will a store bought programmer work? Thanks for any help guys.