Originally Posted by
the Wasp
yes Sir, the Xoars are real loaders, they don't flex as much as APC's. if you go to the Tach page you will see that the FA180 will turn an APC 17x8w at 8900 to 9100.
Jim
8900 with 15% nitro is spot on. It would take 30% nitro to reach 9100.
FWIW, some of the crazy numbers I see on those tach pages is one of the reasons I set up my own testing standards. Apc props, 15%nitro/17.5% oil, F plugs, a sturdy test stand and the static thrust calculator I have posted links to so many times.
I discovered two helpful things in doing that, one is I can determine the health of my engines and the other is that I don't have to take a handful of props to the field to make my plane fly right.
.103 X CC is an excellent way to determine expected hp from our Saito singles set up as noted above.