Looking to buy/build 500-600 fwhp 360

Lurch59 said
Update, I have purchased a set of Icon flat top forged pistons. The original pistons had a zero deck quench area but were slightly dished. I did not want to mill the heads 060 to get 10.1 compression. Now i'm on the other end of where I want to be. The compression ratio will be about 10.9. I can mix a little race gas (ugh). I don't know if putting a little thicker head gasket will get me to 10.5 How about porting a little more to get both better flow, and increase chamber volume? The other thing I thought about is using the box I am going to install to retard timing while on nitrous and use it to retard timing when I am running pump gas. Or, can I get away with 10.9 at 3200 feet on 91 octane? I need an anti knock sensor...

I think it'll be doable but you'll just have to pay close attention to quench distance and little things like smoothing down any sharp edges in the combustion chambers and piston heads as well as run a cam with the right valve events to bleed off some cylinder pressure in the lower RPMs. I would run whatever thickness of head gasket gives the optimum piston-to-head clearance and not for reducing static compression.

I ran a 360 at 10.5:1 on 91 pump gas for years, it was "borderline" but in hindsight I could have done a few things to make it better. First off the cam I was running was way too small and made way too much cylinder pressure, it could have used quite a bit more overlap and a later Intake Valve Closing point. I also found out recently that the timing light I've been using for the past 8+ years reads about 4 degrees lower than actual so when I was setting my ignition timing it was always advanced 4 degrees more than I thought, for that reason I never retarded the timing as much as I thought I did and it pinged a lot. And lastly I was using factory iron Magnum heads; aluminum heads likely would have eliminated all the pinging issues with how it was on the edge but not over.

My current 360 is 9:1 static compression and has ported Edelbrock heads and a custom-grind hyd roller cam from Racer Brown (not huge, around 223 degrees duration at .050"). I had it run on a chassis dyno and found optimum ignition advance at 40 degrees total and it runs on low-octane regular gas all day long, never once heard it ping even on the hottest days.

One thing to note however I am at 5000' above sea level so about 2000' higher than you, not a big difference but still something. Hopefully all of that was helpful and not confusing lol.