cmb91 rs

[bsmtboy2]

I am running a cmb91rs in a 44in twincraft, and i have the Cmb 90 pipe. What is a good length to start at for this motor from plug to weld of pipe. I am running 50% Technology fuel, with a Prather 260 prop. Any suggestion are greatly appreciated.

 

[BigChuck]

Go to the 15cc pipe. Measure 11 1/4 from center of plug to Fisrt tuning band. Go to a 270 Prather.

Ambient temps may want pipe to be longer. Add length if needed. But this will work. It is a proven set up.

Oh, 44.......................Hang on!!! :lol: :lol: :lol:

 

[RaceMechaniX]

Charles,

I ran mine at 11.25~11.75" depending on the prop and fuel.

Tyler

 

[bsmtboy2]

thanks guys i will start there and go with the 270 prop. I am gonna have to wait until next week to find a 15cc pipe.

 

[Thomas Hulbert]

thanks guys i will start there and go with the 270 prop. I am gonna have to wait until next week to find a 15cc pipe.

Head scratch....

90 pipe = 15cc :blink: :blink: :blink: :blink: :blink: :blink: :blink: :blink: :blink:

 

[BigChuck]

90 cmb pipe and MAC products 15cc pipe are two very different pipes.

 

[Michael Costanzo]

hi, i have used a x-665 with a pipe len at 113/4",50% nitro. mike.