paulsr70

I am new to Ls1 tech and need some advise form anyone that can help. i am doing an engine swap on a 1995 firebird with a 3.4 motor. I am swapping it with a 1998 ls1 5.7 motor. I am having trouble withe the harness that goes into the car. the plug ends on the 3.4 is different than those on the 98 ls1. the 3.4 has four set of wires that plugs under the dash. the 5.7 only has three, i need to know which wires i need to re-pin on the 98 harness.