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Reply to "Grey Smoke During Deceleration"

Sounds like a plan.

The only additional  comment that I would have at this point is that you don't want 160psi compression. That's too high for pump gas.

You want 125 to no more then 140. 135 is a good target to shoot for.

160 is an indication that the cam you have is too mild for your application. That's like an RV cam. You are just going to have problems with detonation on pump gas.

You need a cam profile that keeps the exhaust valves open longer to blow off some of the compression.

It should be at least around 235° @.050 to get there.

Be careful of too much static compression with a Cleveland. To me, 9.5:1 is about right.

For some reason the shape of the small chamber heads can't handle too much more without serious detonation.

10.5:1 ADVERTISED is about 9.8 actual. That's right on the edge. 9.5 IS  a safe compromise.

IF you would accept running on pure leaded racing gas of 108 octane, you can easily get 800hp out of these engines.

Last edited by panteradoug