As someone else spoke: the engine was made in a inboard/outboard boat version. That one really turned up the revs, I hear. I don't know if the boat versions are still available. Have to ask K&B. One thing about it: Bill sent the original crank back to me. So if you need another, you can have it.

I dug mine out to re-familiarize my self with it. I have the original manuals from K&B. The engine was designed to run around 22 - 23K RPM according to the manual. Another thing that the supplementary sheets lead me to believe is that they were expecting the user to use upwards of 25% nitro. If you'd like, I can scan those sheets and Email them to you, presuming you obtain the engine.

When Bill told me to prop it to run 18K on the ground, I suppose that he was expecting that it would unload to over 20K or so in the air, on a slick race bird. You used to have to cut and try on that kind of deal. Nowadays you can instrument the model in order to find out how much the prop unloads. The .60-size pipe wasn't my idea. It was what Bill suggested. I never tried it out. I have never even run my engine.

Have fun with it,

CR