The new Tower Hobbies flyer advertises the new OS .46AX engine.

I don't intend to buy it, but the ad includes suggested prop sizes, which could be considered out of the ordinary.
The suggested sizes are 11x6 - 11x8 and 12x6 - 12x7...

This engine is supposed to be quite close in power, to the now defunct FX.


The OS.46FX that I had, with the muffler baffle removed on 5% nitro, used to spin an Master Airscrew 11x6 (black) at 12,300 RPM.

An 11x6 APC would bog the engine down into the 11s as would an 11.5x6 (Bolly and APC). I never dared trying an 11x7...

12x6??? 12x7??? Is this engine meant to be run (deep) into the 10s? Or should it be raced to utilize more of its available output, at around 14K?

The Tower web site, BTW, also lists the 10.5x6 (which is equal in load to a 10x7), but this size was not even mentioned in the flyer.