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Old 07-01-2009, 04:05 PM
JackandJanet JackandJanet is offline
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To add to this, I recall that PHP does not recommend putting in low-octane gas in a high octane tune (i.e., using 87 octane on Level 3 and retarding the timing). The reason is because there are other things that have been adjusted for Level 3 in addition to timing (such as the fuel injector settings and numerous shifting characteristics) that cannot be corrected with a simple timing change.

However, there is no danger in using high-octane gas in a low-octane tune (91 octane in the 87 tow tune). And, in this case, you would increase the timing by +2 degrees. However, because there are other things that have not been adjusted, you would not be getting best performance from the higher-octane fuel.

- Jack
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