I recently purchased a Hobby-Lobby V-Diamond pusher jet....looks alot like a bvm bobcat, or kingcat....Anyhow they suggest a AXI 2212/20 1150kv outrunner with a 8x5 prop....I already own a eflite park 480 bl 1020kv....manual on the park 480 suggests a 10x7-12x6 prop...unfortunately I cannot swing anything larger than a 9" prop due to twin boom design of plane. I was just curious if I can find a happy prop combo for this motor that I already own that will still produce great flying attributes? I would use a eflite 40amp esc, and a 3s 2100mah lipo....everything I have is the same stuff they used except the motor....

Obviously the park 480 that I have turns 130 less rpm per volt applied than the axi 2212/20. Which if I did my math right equates to the park 480 turning 1,443 LESS rpm figured @ 11.1v So common sense says to me that I will need to use a prop that will take a bigger "bite" of air per revolution to make up for the fewer rpms turned to fly the model as well as the AXI 2212/20 with a 8x5. Have I confused anyone yet? Am I looking at the scenario properly? I am kinda green still in electrics a little, I am just wanting someone with experience to verify my ideas, or to steer me in the right direction.

Once again eflite recommends a 10x7-12x6 prop, but I can only turn a 9" max due to width between tail booms....how much do I need to go up in size to make up for any rpm loss over the AXI? Would a 9x6 be a good start??? Or do I need a even steeper pitch? Did try a 8X6 on it and it was very weak on the tourqe...would probably reequire a 100ft (exagerrating) takeoff roll!

Any Assistance is greatly appreciated, and thanks for your time in advance! Whew...I will shut up now! Bye!

Regards
Craig Davidson