Ed, last night I found information on another Cozy with 6 cylinder 
Subaru 230 HP, same reduction ratio and the same prop.
At fine pitch like me, he was getting 4400 rpm and was able to get 
2000 fpm at 80K on take-off.
I fully intend to do fast taxi tests before flying.
Buly

Buly,

 

Another option is to check the static thrust (in pounds of KG if you are so inclined) at T.O power. This might be somewhat difficult with a pusher, but I imagine that you can chain, or tie the main gear to a structure in back of the airplane (keeping the tie-down mechanism out of the prop arc.) Comparisons for pushers might be tough, but you can probably get comps from RVs that are flying.

 

Rich