Join Date: Jan 2001
Location: Lubbock, TX USA
Re: Does Octane Matter????
Back to the octane issue.
Octane rating is basically a fuel's degree of refinement. The more refined, the higher the octane and the higher compression you can run without detonation. Assuming a combo is optimized with timing and carburetion, you can run pi$$ gas with low compression but if you try to run that same stuff in a 15:1 race engine, it'll detonate itself to death. One side effect of the refinement process is that the higher the octane, the slower the burn. So, if you have a 9:1 engine that's happy on 87 octane, it'll actually make less power on 110 since it takes longer for the flame front to burn across the piston top.
Later model cars can make more power with higher octane, though. The computer controls timing and it'll push timing as far as it can without detonation. You will make a bit more power on higher octane with these engines, but not past about 93. It's not instant, either, it takes time for the computer to relearn the new fuel and timing scheme.
FCS Harmony Racing
Momma always told me not to look into the eyes of the sun.
"But momma, that's where the fun is!"