NR 91 Head Clearance?

[Blackout]

What is working good on 50% nitro?

Thanks!

 

[RonShaw]

Craig,

Start at .012-.015 for 50%. If anyone is specifically using 50% I am sure they will post to help you narrow this down even further. Thanks.

 

[John Knight]

15-17% will work fine and not overly stress the engines or bearings. I always focused on good reliability and engine longevity first. Still do.

 

[Mark Bullard]

The prototype engine that I have been running has about 10 gallons of fuel run thru it and it has not been baby. Head is set at 0.012" and running 55% with 22% Klotz oil

 

[Blackout]

O.K., thanks guys.

I'm at 0.015" now, but the engine is acting like it needs to go lower, so .012" it is.

I ordered a head shim kit last night.