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Octane ratings

Posted: Tue Sep 01, 15 3:23 pm
by sublimemike
What would be our equivalent to US 100 Octane? I know their fuel is rated different to ours.

Posted: Tue Sep 01, 15 4:17 pm
by RobTwin
Not sure of the exact figures but I read somewhere that you add 5-6 points to the US number to get the UK/EU equivalent... :-k

Posted: Tue Sep 01, 15 5:44 pm
by latil
https://en.wikipedia.org/wiki/Octane_rating Yes 5 points is about right.

Posted: Tue Sep 01, 15 6:25 pm
by John
So 100 in the states would equate to 105 over here then? ;)

Posted: Tue Sep 01, 15 9:31 pm
by sublimemike
Seems so John. I've seen something in the states but it needs 100 Octane minimum. It's not going to happen unless the motor gets pulled to pieces , pistons etc 12.5- 1 compression - just too mad, I thought it was going to be. Race fuel only it sounds like.

Posted: Tue Sep 01, 15 9:57 pm
by John
Yeah sounds a bit much. You could try retarding the timing but all a bit of a gamble

Posted: Tue Sep 01, 15 10:10 pm
by sublimemike
Yes John , 454 Chebby , Ally heads, the timing is around normal 18 intial 38 max, possible scope to decrease.....