Rudeboy

What prop should I be looking at for some good speed...? Bird is fairly slim, but no F1 plane...

I'd like to get 150 or 160 out of it...

A G62 is capable of about 6.6hp on a pipe at 9,500 rpm...

I have no experience what so ever with planes bigger as .50 size...

max plank

17x18 shuld be about rigth.. ho makes a prop like that ?

Rudeboy

APC

OLD_SLOW and in the WAY

i did a full mod job on my g62 with great results, the exhaust timing was left stock but the piston skirt on the intake side was slightly cut to raise thats side timing a bit , the piston was golfballed lightened and windowed. the transfer were opened flowed and intake side was eyebrowed, crank was knife edged and the rod end trimmed. gaining rpm was not my quest but building torque and hp in the rev range below 10,000 rpm. it went from a static 7000rpm with a 22/6/10 to 8000 with a 24/12 static.
remove choke and fill holes left by it. re work the carb opening to a smooth bell shape , use flathead screws to reduce intake drag. and dont use a velocity stack ....there are only a very few shapes that dont cause a restriction and i havent seen any of those made yet. pipe length is very critical, you can slide pipe whilst the engine is runnin at full speed with a tach then fix pipe at that length. puttin a small GPS on board will give you speed differences as well with an onboard tach. the cylinder and parts are not from a G62 but is represenative of what was done to my G62
the picture of the velocity stack is the most efficient of the designs... a carb draws air in circumferentially and the standard B&B stlye will cause a 5 to 8% retstriction over an open bell mouth carb

Flyer95

My Feedback: (1)

Hi Rudeboy,
I had a 90" little Toni , for a few years ago, powered by a Brison 5,8 gas engine. It was very heavy at 32LBS []. Build from plans and was much more bulky than the F1 racers and did only about 120MPH. I used a APC 24x14 @ 7200rpm on a muffled tuned pipe. How much is your plane gonna weight? If your G62 can turn that 17x18 about 9000rpm, and the weight is less than 18LBS, then 160mph should be an easy match. Good luck

Rudeboy

Flyer, your speed sounds about right on that prop. You need some serious pitch to get some serious speed on these gassers. I believe the giant scale F1-GT guys are using 18x20 props on the GT80 twins.

16 to 17 pounds should be possible depending on finish.

I'm intrigued by Fastrats G62 mod job... from 7000 on a 22x6/10 to 8000 on a 24x12 is quite impressive!

Flyer95

My Feedback: (1)

Rudeboy,
My little Toni was just too heavy and too bulky for fast speed. So in this manner it was a failure []. But it fly very well and was an easy lander, and looked good to. Are you gonna compete with your airplane?

Rudeboy

We've got difficulties keeping Club 20 and Quickie 500 alive over here... so no, I'm not going to compete... just for fun!