Side Port 21 CMB, Any Knowledge??

[crrcboatz]

With the discussion on the Picco 21 SP, I was wondering if anyone has any idea on the hp/rpm rating on an older CMB I have NIB. I want to put it in a Pistoliro Bandit 21 Mono as a sport boat and would like to know what to expect with an OPS 29-40 pipe and 40% nitro.

Comments appreciated

Regards Curt

 

[tracerbob]

Is that the one with the round exhaust port? If it is, I ran one in a small sprintcat in the late 80's. Thing would scoot! Got sixth place in the 91 winternats in 20 hydro. To me thats not bad for a cat.

 

[crrcboatz]

Yes it has a round exhaust flange. Rod Guerity adapted a nova rossi head for it and did some timing work on the cylinder. I know it will not run with today's Macs and CMBs but for a young man in my neighborhood in that hull would it be a good first 21 mono or not give him much of a chance if he decided to race it?? The boat would remain mine but he thinks if he gets the hang of the thing his dad might talk me into building him a better rig for Christmas.

The lower nitro, 40% and the pipe I spoke of set at say 8 1/4 would be about the best I can offer him without letting him run my AC 21 mono which I do not want him on the wheel with.

Anyway, if anyone has a feel for this let me know. I am just not a k&b guy but I would like to think this motor would keep up with the stock k&b 21???

Regards Curt

 

[tracerbob]

You would'nt have a source for pistons/sleeves and rods would you? I threw a rod in mine (a sad day) and I would like to revive it as a play motor. Also, mine had a slide carb and the crank had three grooves cut into surface of the crank center. sort of a turbo thing going on there. I think mine was originally a car motor. I ran a x440/3 tucked in real close to the tunnel to let the thing scream.