Originally posted by Jazzy
By way of comparison, a Royal .46 was running a MA 11X6 prop and revving up quite a bit with healthy speed and acceleration. The prop was switched to an APC 11X6 and the engine ran much differently. Low speed acceleration improved but top end speed and RPMs suffered.
Jeff
Jazzy,
The fact that the Top End RPM suffered is due to load and increase pitch from the APC prop. The MA maybe rated at 11x6, but in reality it's probably not. On the other hand, APC are pretty accurate when in come to pitch and that's why you noticed the engine suffered from it. Put a pitch gage to it and you'll know that the MA 11x6 in not what is all up to be.
An 11x6 prop on a .46 is Too Much prop for the engine. A good prop would be 11x5 or 10x6. Hope this clarify the misconception with engine suffering from APC 11x6 prop.
Sam