More props & numbers, basically the same setup as above. All APC props this time:

11X 12 at 12,750 and the 11X14 at 11,700 on 15% and a few hundred less rpm on FAI fuel. I could tell the engine was working hard on the 11X14 by the richer needle setting and the extra smoke, it didn't seem like it was static stalled like I have seen the 10X10 props do on other engines.
The pipe is a bit short for these prop to peak on the ground but it may right where I want it in the air. Testing-testing!

An 11X11 or 11X12 may be the best prop to run on my Phoenix Strega if it will hold or unload rpm as the plane moves faster and the prop hooks up. Testing testing.

Other props I tried to answer some questions: APC Sport 13X8 @ 12500 and APC Pattern 13X9 @ 11700.
An A5 glow plug was tried but it lost 200 rpms with these props, went back to the OS #8.