1sicss

iTrader: (3)

I've been reading a little bit about the differences in the ls1's from 97' to 04' and was curious if anyone had done this already, upgrading from ls1 heads and intake to ls6 heads and intake. I've been wanting to do this and was wondering about how much more hp I will pick up by doing this. What I have is a 98' Z28 with all the boltons minus the intake upgrade. Any guesstimates of the hp I would pick up by doing thism and keeping the stock cam and later doing the 1.8rr's.

NonGoggleGuy

Well, the LS1s were rated at 305, and the LS6s were rated at 325. The major differences in the two engines are the oil valleys, intake, heads, & cam.

Red99TA

iTrader: (11)

If you're talking about an LS1 motor with the LS6 intake then yes it's only rated at 325-335 HP. However an LS6 motor with the LS6 heads and cam is rated at 405 HP unless you're talking about the '01 LS6 cam and then it's 385 HP. Honestly if you just change the heads and intake over then I would think you would gain around 30RWHP. Best bet is to changeover to the 243 (LS6) heads along with a nice cam and you'll push 400 RWHP easily.

SweetS10V8

iTrader: (4)

LS6's were rated at 385hp for a year or so('01 ish??), then went to 405hp...LS1s were 305-325hp From what I remember.

silverz28camaro

iTrader: (20)

you should gain 20rwhp if you do the intake and heads only. Don't waste the money on the rockers. Keep the stockers, they are just fine for street applications. Either also get the ls6 cam, or a 228r cam. buying a cam is cheaper and you get more power. If you run the 1.8 rockers then you limit the cam choice in the future.

NonGoggleGuy

You're right, but the rwhp all depends on the car it went into.