Re: max compression 93 octane.
If you lighten the rods or change pistons, balance the rotating assembly. The dynamic compression ratio is a factor in coming up with a combination that works. Simply put dynamic compression is the effective stroke. It is changed by the closing of the intake valve ATDC. For example my engine has a static compression ratio of 8.7 to 1 and with the intake valve closing at 59 degrees ATDC the dynamic compression is 7.1 to 1. I need a low number because at 15 psi the ratio is over 14 to 1 . If I ran this cam on pump gas 11 to 1 would be managable with a timing curve peek of 32_34 degrees and a 13.7 stoich fuel mixture. Mild cam engines run 10 to 1 all the time. Some were that way from the factory. Modern honda K series engins and GM LS3 engines run 11.2 to 1 stock. I would build with no less than 11 to 1 just don't get greedy with timing and tune safe.
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