what octane

[300exboy #15]

i was wondering what octane level should i run in a 300ex motor with a wisco piton kibbles heavy duty valve springs a 400ex carb dmc exhaust web cam stage 3 no air box lid and twin air air filter

[400eXr1d3rZ]

what ratio piston do you have? 10:1 11:1 12:1?

[Mx_523]

Anything above 11:1 compression piston requires race gas. If you have a 11:1 or lower compression you should be find with pump gas.

[300exboy #15]

11:1

[heath720]

i would just run premium pump gas unless your really serious about racing you could run race gas.

[bwamos]

Premium Pump is just fine on an 11:1 300ex.

If you get detonation.. you're running lean.