black cat
New member
I have an 05 jimmy with 4.3 vortec that i,m taking out. i have my choice of an 02 5.7 vortec with 255 hp which would be a much easier install cause it is identical except for 2 extra cylinders.no wiring changes except for an ecm reflash. OR an 03 5.3 with 285 hp. i would have to get an ecm and wiring harness but i don,t know how big a mod this will be to get in. the oil pan looks deeper but i can,t tell if it is the way. any input is much appreciated.