which is faster- VP C-11 or C12

[FastbackTom]

Originally Posted by Alan Roehrich

The problem with the "burn rate, burn retardant, octane" theory is that there are a lot of Stock and Super Stock racers who keep a 5 gallon sealed pail of VP C25 in their trailer for heads up runs, and switch to that from C11 or C12 for a heads up or class run. If you look at the octane ratings, if the "burn rate, burn retardant, octane" theory held true, every one of those guys would slow down, unless they were retarding the timing and/or detonating on C11 and C12. C25 will also show better on the dyno as well. And C25 is capable of supporting 15:1 compression.

Good stuff, Alan. So help me understand what's going with C25 octane 113 versus C12's 108 octane...

Why would a guy be able to just throw in C25 and pick up power in a stock or super stock engine, with relatively lower CR? I believe you, it just doesn't add up inside my brain.