Does any one know what octane is best for an FC?

 

87 or even 85 if you live where its available for a N/A (GTU, GXL, SE, Convertable) 91 or better for turbo

 

Cool thanks. I live in S.F. 87? Realy? I thought it would require higher octane. I remember I had and 85 GSL-SE. I ran it on the cheep **** when I first got it. I put 89 in it and it gave it bigger *****. Or at least it felt that way.

 

For a S4 or S5 non turbo, the lowest octane you can get will give you the most power.

Remember it is not the Octane that gives you power. Octane is the rating of how much the fuel resists detonating when compressed. Higher the Octane number, the more the fuel resists detonating under compression.