Re: Compression test - pressure 2 high???
Stock smog engines had some pretty high cranking compression,but that seems too high. The very very weak cam timing and late intake centerline gave them more cranking compression then the old school muscle engines. They also required an EGR valve to run at cruise speed,and the distributors with the low compression EGR equippend engines would cruise at about 55 degrees total timing at 2000 rpm. That was only with the vacum advance hooked up though. If you dont have an EGR valve and are running a smog era distributor with the vacum advance hooked up,it will almost always ping,and no amount of octane in the world will fix it. The cylinder pressure is peaking way before the piston reaches TDC and thats what you are hearing. By introducing exhaust gases into the intake charge it slows down the combustion process a lot.
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