Quote:

Quote:

Octane is a measure of knock resistance. More octane will burn slower and not want to explode (knock). A higher octane will not produce more power. More powerful engines run the high test to match wild compression ratios, not because the gas has more bang in it.

Run the lowest octane that doesn't knock with your preferred spark advance.



Thank you. A very sensible answer!



We race circle track with crate ZZ4 chevy motors. These are untouched long blocks. Sealed from the factory.

We've done extensive dyno testing with the 93 and 100 octane available track gas.

The 93 and the 100 octane gave the same dyno numbers. BUT the carb jetting needed to be optimized for each gas.