[Aubrey N Bruneau]

I just bought fuel a few days ago... wanted C11... only had C12.
He said that the C11 is for oval track racing with restrictor plates and up to 11:1 compression.
To me, that translates to a typical Stocker engine... often somewhat limited in optimum carb CFM, and modest compression ratio.... IE, cylinder pressures that are not right out there.
Sounds like C11 would be the fuel for most Stockers ?
But damn, this stuff can be hard to get around here.

If your'e under an actual 10.5:1... I'd suspect the C11 would be more efficient.

BTW, I'm no whare near the xpertise level of some of the guys here, but I DO tune...
so don't take me as the gospel... but just a few words from it