What Octane To Use

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Senior Member
With a 10:2:1 compression, what octane gas is the lowest i can safely run, and at what compresion levels do i need to start running higher octane gas? Tahnks for the help guys.
You might be able to make some generalizations about octane rating and compression ratio...but it is just guessing. The head design (combustion chamber), piston design, valve area, IM and EX flow characterstics and camshaft have too much effect on the dynamic compression which is acutally what utlimately drives how much octane you need to prevent detonation.

To the best of my knowlege, and experience, most motors over 10:1 would run best with 93. Even my Z6 runs like crap with only 87. Run 93 for best performance.
Start high and work your way down. Your engine will run best on the lowest octane that does not lead to pre detonation under load. If you just want a real generic guess at least 91 octane.
does anybody have any good recomendations for a good octane booster, in cali we only have 91 pee water, and if it makes any diffrance its a 1st gen b16a, thanks