Newbie 318 piston question
- Thread starter odie 2882
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Garys72Duster
Well-Known Member
I hear ya! The builder must have planned on building a strong running engine, it looks like. It has roller rockers, and receipts show a hyd cam, the CRS XE274 H 10 Cam and lifter set, ordered thru Mancini in 2007. Probably will be needing some kind of octane booster in this one!
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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big cams do not automatically mean hi-octane gas.
It's all about heat in the combustion chamber, and the presence or absence of hot spots. Cylinder pressure is a big part of controlling it. This does NOT automatically mean Compression Ratio, altho that's a part of it. As is elevation, inlet air temp,coolant temp and AFR.
With a given compression ratio, pressure actually drops with the later-closing intake valve, of a bigger camshaft.
It's all about heat in the combustion chamber, and the presence or absence of hot spots. Cylinder pressure is a big part of controlling it. This does NOT automatically mean Compression Ratio, altho that's a part of it. As is elevation, inlet air temp,coolant temp and AFR.
With a given compression ratio, pressure actually drops with the later-closing intake valve, of a bigger camshaft.
Hence why the compression ratio is raised to compensate and high octane used for when it’s needed later when the engine starts to make power in its operating RPM band.
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