Ideal Octane???

[Sephrion]

whats the ideal octane to run in a 4.6L stroker with 9:1 compression??? I've heard 91 or up but with prices today how will running low octane affect performance? considerably or not?

 

[Dr. Dyno]

Try 89 octane and if the engine doesn't ping, you can then try 87 octane. Use the lowest octane fuel that the engine can burn without pinging.

 

[MudDawg]

I agree with Doc...not only is it more economical to run the lowest octane fuel possible (without having detonation) the lower octane fuel has more BTU per pound of heat energy, increasing the possible HP output.