Ok, I've got the Golberg Tiger 60 with a Magnum xl-80rfs on it. Currently running a 13x6 prop. If I go full throttle and pull vertical, the plane will climb, then slowly slow down then stall, I want the plane to be able to climb vertically(unlimitted), so I'm being told I should go with a .91 size 4 stroke for the added power. I just found a web page that recommends a 12 X 8 prop for my motor.... will this help climb performance, or make it worse for my plane? Or should I go with a bigger motor? I was just told at my flying club to always go with a bigger motor than what the manufacturer recommends, Golberg recommends a .70-.80 4 stroke for my plane, so I went with the .80, the guy I spoke with told me to go with a .91 and I'd have great power for all future aerobatics....
If I go with a .91 4 stoke, any recommended prop sizes? any advice would be great. Thanks