Thank you guys! Ola, contratulations for your flights at WC, I was there!!!

From the various replies it seems this engine has huge flexibility!!! I din't think that it could spin a 18" propeller!!!

I see that in local contests here in Italy the APC 16x14 is also quite used: it could yeld little more speed vs little less vertical thrust?

Everybody agrees about 15% nitro?

Thanks again for your help, very appreciated.