is there really a difference in gas?

[CHEAPCHEVY]

Originally Posted by 00SSvert

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If I remember correctly the LT1s (= 9.5:1) are running a slightly lower compression than the LS1s (= 10.1:1), stock setup of course, which would mean the can safely run the lower octane, 89 probably not 87.

Pretty sure my LT1's compression is 10.25:1. Once, on a trip I had to use 87 octane, and man, she didn't like that at all. I could even hear a little knock when I got on it before the PCM pulled out some timing.

[theCHEVYkid]

i had to do the same once when i was up in canada, they only had 1 grade of gas on that island, i had to put 87 in so i got a bottle of octane boost which help a lil prolly, but the next week when i went to gas it up they had sold out of the octane boost, it was limping around pretty bad till i got back to the main land