BC12D-4-85
SPONSOR
Fairbanks, AK.
We’ve all heard of bootleg 8.5 pistons in a ND 320 with no banana plates, and I’ve always wondered, say a guy is running a 82x42 or 41 borer, are his cylinder pressures any higher with the 8.5’s than they would be with the 7.0’s and a 74x56 or 58 cruise prop? I’ve always wanted a transducer to measure it... maybe some of the engineers/mathmeticiams here can give us a rough idea
Which prop has the lower static rpm on the same engine might be one question. Lower = higher load BMEP at that static rpm - maybe? Then in flight same deal...which produces the higher load or requires more manifold pressure (install a MP gauge to discovert) to achieve the same rpm....the cruise prop I suspect loads the engine while the Borer produces less BMEP.
Gary
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