Boosted question: ls1 vs 5.3 gen 3
Boosted question: ls1 vs 5.3 gen 3 Hey guys, so I have a 120,000 mile ls1 runs great, I also have a 5.3 with same miles. I plan to run between 575-700hp, turbo is a s475, will go pump gas and methanol or just e85(haven't decided yet on fuel) system is dual Wally 255s and 80lb injectors, I have ls9 gaskets, tick stage 3 turbo cam(came off a 5.3 but will still work in a 5.7 right?) valve springs pushrods ls2 timing chain ect.
Now I have 317 heads I can put on the ls1, would the 5.3 sbe or the ls1 with 317 heads sbe be better for boost?
Thanks
Now I have 317 heads I can put on the ls1, would the 5.3 sbe or the ls1 with 317 heads sbe be better for boost?
Thanks
TECH Fanatic
Joined: Jun 2013
Posts: 1,163
Likes: 16
From: Avon, Ohio
I'm making 850whp on a bone stock Ls1, so anything over that should work fine. 
I am seeing zero restrictions in the tune from my stock heads. I am not logging backpressure, but it like the timing and was making 30hp per Psi when we stopped the part at 22psi.
I am seeing zero restrictions in the tune from my stock heads. I am not logging backpressure, but it like the timing and was making 30hp per Psi when we stopped the part at 22psi.
