91_RS_LS1

Are there any major differences between the 99+ LS1 F-Body harness and the 5.3 truck harnesses? Would a 5.3 harness run the LS1 without modification? I've read that the injector plugs on the truck harnesses are different from the car motors and that the IAT and MAF sensor wiring is different. Thanks in advance!

jkwalkercchs

iTrader: (21)

im looking and im guessin they are considering people put fuel rails and injectors on the trucks and they just buy ls1 injectors

ls1nova71

iTrader: (4)

Looks like you answered your own question! Those are about the only real differences. Other small differences are extra pinouts for electric fans and smog stuff most people don't use anyway.

91_RS_LS1

So, I'll need to swap the injector plugs on the truck harness to car plugs before LS1 type injectors will work with the harness?

ls1nova71

iTrader: (4)

Thats right, somewhere I've seen adapters so you don't have to cut your harness, just don't remember where I saw them! Would also have to change the MAF connector, truck uses six pin connector with iIAT built in MAF car uses three pin connector and a seperate IAT plug.

tvrbo

iTrader: (2)

are the pcm pinouts different, or can you use a ls1 pcm with the 5.3 harness? anyone know a good place to locate one?