ORIGINAL: servoguy
Hello,
I am not sure if any one can help, but I really need some comments on my KMP GEE BEE with the GMS 1.20 engine....
I just bulit it up, have no idea what size of prop to use, the owner of the hobby shop told me to use 15 x 13, but according
to the instruction manual of this engine I have , the range is within 14x 8 ~ 16 x6..... and I just learned from the introduction paper
of my friend's GMS .47 , it says GMS1.20 uses 16x10 for sports,16x8: for racing, 18x5, 18x6 for scale ??!!
Does anyone have the experience on this engine with a scale plane like Gee Bee ??
Thanks...........
THe KMP is like the GP just a little heavier and the wings are 72"insted of 66" In my pic I posted one is GP and one is the KMP. I'm not to familure with the GMS, but I would start with the 16X8 or 18 x 6 as my second choice. The 15 in prop won't be out past the cowl very much.The first # is length and second is pitch. The reason he is saying go with the 15 x 13 is that the motor will rev high and the pitch will give you more forward thrust. Pitch equates to feet forward and will mean speed, but will also load up the motor and you need wind across those wings. I'll check and see whatI have on mine later and get back to you.