ggroyal1

What is the best prop and rpm for the OS91 in a Little Toni? I am using a 14x7 APC at about 10,500 rpm. This is a great flying plane, radar gun shows 107mph. Very nice ARF.
Thanks,
George G. Royal

Flyboy Dave

My Feedback: (21)

If you want speed....you will need a smaller diameter prop, with a lot more pitch.

The 14-7 APC is robbing your engine of too many RPM's. [X(]

juanpipito

I had a 12x10 apc in mine, its the best prop for that engine if you want speed.

rmenke

My Feedback: (13)

juanpipito:

The little toni is a great sport flyer, do not think you are going to get much more out of it, maby 120 with a Jett 90lx or OS vrdf, the best of the best BVM 96. Your OS 91 just does not have the beans needed for any more speed, the plane is very draggy, not intended for anything more than sport flying. If you want to go fast, get a gp viper or similar q-500 and spend a little on a nelson or jett and you should get a cheep 150-160, enough to see if you truly like the fast stuff. If you are stuck with it, you are going to have to spend some bucks to go fast, speed equals money, there is no reasonable substiture. A great start is a Jett 60lx in a formula airframe, engine $425, airframe from 250 to 800, plus some decent gear that is strong, durable and small. Yes, gonna have $1200.00 or so in a good airframe. You can save some airframe dollars if you like to design and build. A easy project is using the Q-500 airframe moments, expand as needed to carry your selected gear, and cowl in the engine area. Stick a viper or similar wing on it cut down to 45" or so. The jett will turn a 8.8 X 8.75 prop 20 to 22k sized and weighs around the typical46 sport engine and runs like a sport engine at the lower end, great idle and transition. Note that current good Q-500 times are near 200 mph with the 52" wing, yours at 45" is more than adequate for the weight and should bring you way up there in the speed area. If you are a novice to speed, the engine will throttle back and let you get used to the thing. Yessssssssss, will be scary fast and still turn. Will become a lawn dart if you do not use good gear. Mine on its first flight had the new Cearmark switch go intermittent while wfo. Got it back when just a speck in the sky, had a few seconds of control, able to turn back to the field, yank throttle back and add some up into the mix. Thing came home, got more control just prior to landing in the field about 400 yards off. New switch, added some nose weight and good to go again this weekend. If you are not a tallented pilot, start with a sport 46 and work your way up. Mans gotta know his limits. ENJOY

buddude8

My Feedback: (10)

I always had my best runs on my os with a 13x8 apc pattern prop. I also changed out my needle with one from a os61. the 91 needle does not give you the fine tuning adjustment like the 61 needle does. That engine is easy to burn up if run to lean.