legacycentral bbs

well i am new to the turbo scene.

what octane can i run?

around here i can get 90 91 and 92. but no 93.

the car will see stock boost levels untill net summer at the soonest. even then it probably wont go over 10psi untill i add a intercooler.

oh, its a '94SS.

I think Subaru specifies a minimum of 91 octane. At stock boost levels 91 will be fine. You might notice a little improvement with 92.

sounds good to me.

The higher the better.

I'd run C16 if it was cheap enough, and could be pumped directly into a car.

Oh, and if it didn't kill your engine...

If you get too high of an octane, it will actually hurt performance depending on how stock the engine is. 91-93 octane should be fine tho.

91 is MORE than enough for stock boost. Besides, even if its shitty gas, the computer will pull timing to reduce any knock, which there will be none anyway.

Run the highest you can get. It's cheap insurance. The extra cash per fillup is minimal and will be less than $100 per year. Our ECU's are very good about squeezing extra power out of good gas, I'd rather the car keep advancing the timing to make extra power rather than backing it off to save 60 pennies on a fillup. Plus, typically the higher grade is just better gas.

I've noticed even regular is more then enough for non agressive driving. And even when u give it a little spurt of power there is no sign off detonation.

Mark,

I always use 93 octane. Its a little pricey but worth it.

I run Ultra 94 almost exclusively. The only time I don't is if I'm out of town and can't find a Sunoco or I'm at the track running GT-116 !

When I hit the Dyno, i'll run race fuel. There is a place that sells it down the street from me. Maybe I should get a few gallons when I need to fill up next...

I use at least 91, because thats just the highest that most stations i find have.
Anytime i find the higher octanes I get them without question.

The required octane needed will depend on elevation....even though it's less of an issue for turbo cars. 91 is fine.