ORIGINAL: rainedave
MJ, that's interesting because APC lists the 12.25x3.75 as a C/L prop and I've always suspected that the G.51 was originally developed as a C/L engine.
AFAIK the G51 RC engine came out first and then the CL version which has a different liner with lower exhaust timing. The CL version has the exhaust opening at 70 BBDC while I believe (never had one to check) the RC is about 74 BBDC. Maybe sometime I'll fit an RC carb to mine and see how fast it'll turn similar props. I won't be using nitro though
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