My home inspection of Speedmaster heads

PRH said

The motor I tested that made the 589hp...... with the untouched plug holes....... made peak power at 33*.

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I can't answer that, but when you recess the plug like that, it affects total timing.

It's also probably on another light it may have been 38!!!!! And on another light it could have been 30.

As long as the plug says it's happy, the number is what it is.