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Discussion Starter #1
whats the most you can do with a 460 and it still run on 87 octane, on 92?

whats the highest compression you can run pump gas. is it possible to run an engine on 87 and it not be streetable?

I'm looking to make my truck barely streetable but I don't want to try to get so much out of it that I can't take it to work and back. I'm lookin for a parts list so that over the next few months I can try and find everything as cheap as possible then build the engine.

whats your opinion, what do you run?
 

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THere is no one single compression factor. The need for octain depends on a dynamic equation, that includes static compression, cam duration and the resulting compression in the cylinder. Combustion chamber shape and finish, spark plug heat, and piston shape and design also play part in how much octain a combination might need. Additionally and in my opinion most important is the build design of the engine. Quench, is seldom spoken in Chevy land, and thats also where you hear the most people scream about anything over 9-1 requiring race gas.
Scott J (aka mad porter) has actually worked with some gas passages cut in head areas to take quench to another level. But less than that, for the average idle to 6500 RPM engine, I would target .035" quench if your looking at a daily driver. This requires attention to a few other areas. Ie proper piston fitment to prevent excessive rock and or a differing closure of the piston to the head. A selection of a proper head gasket, and of course cutting the deck height and selecting a rod length to typically get the piston about .005 or so above the deck height.

With proper quench, and a moderat cam there is no reason why an iron headed engine couldn't run about 10-1 static compression and 87 octain.

When you add in the heat dissipation of an aluminum head, then your talking combinations that can run *and need* to run about 12-1.
 

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Discussion Starter #3
wow

wow....

i see this star shooting over your head and I hear "the more you know" in the background. THanks. answer one question and now I educated enough to have another 10. joking aside THanks alot for the info....gotta go hit the books some more and learn some more.
 
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