fuel octane rating for header and cr10ek plugs

[almond1000]

I have a 09 nytro shorty and I just installed the excell header and cr10ek plugs from ulmer racing. what is best octane fuel to run with this set up 87 89 91 or 93? here all fuels have 10% ethanol except for 93 octane

 

[shadow44]

should be fine to run 87

 

[sleddingfarmer]

No reason to run higher octane than 87 unless your raise compression.

But I would fill it up with Ethanol free gas if the sled is going to be sitting for a while, and before storage.

 

[thetruck454]

Timing and compression are set up to run 87. No need to run any more.

 

[bottlerocket]

Allen Ulmer sez 87!