500WHP+ N/A possible??
Last edited by SS1875; Jan 5, 2007 at 04:09 PM.
My 402, with a th400, and a 6000 converter made 445 rw... so it would easily hit 500 rw with an M6 in it, probably even with a locked converter, if I could do that.
I'm running a mid 240's duration cam as well.. but the sompression is a little too high for 91 octane. Even with the compression dropped to say 11-1, I think it could still top 500 rw with no issues thru an M6 Just plan on having a big cam in the car, with a small high 230's duration like you're thinking, it's not gonna do it that I'm sure of.
As everyone has mentioned... with more cubes it is easier to get 500rwhp and keep it very streetable.
A friend had a 402 with Stage 3 5.3 heads, FAST 90 intake/90TB, long tubes, 91 octane and made 490rwhp with a tiny 236/236 115LSA cam. It idled near stock and had a nice wide powerband. If it were me I would've run a much bigger cam for more mid/top end power.
In my 346ci stock shortblock I ran a 233/239 112LSA with AFR 205 heads and GM MLS head gaskets (.024" milling to approx 62cc combustion chambers), LS6 intake, ported TB, long tubes with cats/dual 3" exhaust. It was around 10.7:1 compression. It made 440rwhp and only 385rwtq. It had good driveability (nowhere near stock), pulled like a freight train from 4-7K rpm, and trapped nearly 128mph in the 1/4 mile n/a. (2950lbs with driver)
In hindsight I would've milled the heads more (for 11.2:1 compression), used a thinner head gasket (cometic), run a FAST 90/90 intake setup and achieved 470rwhpish and easily more than 400rwtq thru my exhaust.
With a bigger cam you can achieve more power.... but driveability, fuel economy, low end power typically suffers.
If you have the funds a 402 (LS2 block) or 416 (L92 block) both with 4" stroker cranks, and some good heads/intake/headers/tuning will easily yield 500rwhp. To get to 550rwhp will take some excellent heads, much more aggressive cam, and total attention to the build up details.
I hope to make 575rwhp n/a with my LS7 buildup on 91 octane (11.25:1 compression) and 7300rpm redline. We'll see in March.









