bonedaddy41 6800 with a 24x10 is to much for this engine. It will unload in the air and the max hp is based on that type of rpm but 6150-6400 is perfect for this engine. Be very careful you hang a ring at that rpm or spilt a piston and you will have more problems than you want. I think you have the exception vs. the rule with those types of rpms.
ORIGINAL: bonedaddy41
I am running the Evolution 58gx in my 27% BME Oracle Pitts
and am VERY happy with it. The Pitts weighs 19# and has unlimited vert swinging a 24x8 (7000rpm) and 24x10 (6800rpm) on 30:1 break-in mix running rich enough to coat the landing gear and left wing. I'll let you know how things go once I start leaning it a bit.
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