Compression vs Octane

[probert]

I'm currently running flatop pistons in my 350 chevy with a compression ratio of about 10.3:1. If I change to a .100 dome piston and bump the compression up to 11.3:1 can I get away with 93 octane gasoline?
Thanx

[Salvatore]

I think so. It is important to run some lead for cooling and lubricating purposes. I use Jack Podell's REAL lead octane booster that gives me around 100 good octane. I mix like 12 ounces to around 12 gallons of 93 octane. I am running 10.5 to one in my 1969 Z/28. NO problems with that stuff and I have my timing around 40 total degrees. Sam

[gemleeus]

i've talked with engine builders about the same thing before and some say its alright and some say you better run 100 octane or better. if i had a substancial amount of money in a motor i would run a higher octane than 93.

[PxTx]

Your camshaft selection is critical. Your mechanical compression may be high, but depending on the cam, the actual squeeze may be more or less. What cam are you running?

[probert]

I'm running a Comp Cams XE 274. I believe it's about 480 lift with 230 duration? By the way I can't endorse these cams enough

[SMGCO]

I agree totally that your cam selection is critical to how much static compression you can run. The larger the cam ( ie duration ) the more low rpm cylinder pressure will be bled off which will allow you to run higher static compression with lower octane gasoline.