RE: OS FGR Blackhead vs Webra 10ccm Blackhead
I got a chance to run these two engines yesterday. Unfortunately, the battery in my tachometer went dead before I could complete the tests.
The last time I ran the Webra I was not happy with the transition. This time I added an extra head shim (total of two) and used a new Fox Gold RC Long plug. Wow. The transition is as instant as any of my new OS's. I can let it idle for a few minutes and it will go to full throttle without any hesitation or coughing. Very quick and smooth. So, if you have an old Webra with the early TN carb, try my remedy.
Webra Blackhead. Stock muffler. All props OOP Top Flite wood Super-M's. Powermaster GMA 5/22. 65° and clear.
11x7 - 11,691 - 1.2hp - 7.2lbs static thrust
11x7.5 - 11,406 - 1.19hp - 7.16lbs static thrust
11x7.75 - 11252 - 1.18hp - 7.11 static thrust
11x8 - 10,861 - 1.09hp - 6.76lbs static thrust
What is interesting is that in a magazine ad from 1970 Webra claimed 1.72hp per cubic inch. Multiply that by .61 and you get 1.05hp. That was either a conservative rating or my engine is on the strong side.
I will test the OS FGR next to see how it stacks up. Stay tuned.