McCulloch engine - what size?
 

I just purchased a conversion McCulloch engine made form a new cylinder. The seller is unsure of the displacement but it seems to be about 40 cc. It weighs 4 lb 8 ounces bare but with sidemount muffler, so probably 4 lbs bare. All we know is that it turns a 22 x 8 at 6000 vs 5200 for the same prop on my well run-in CH Zenoah G38. It turns a 20x10 at 7600. Does anyone know what size engines McCulloch made in this range? Their modern Chinese stuff is 32 and 35 cc. It unlikely that a 35 would turn a 22 x 8 800 rpm more than a good G38.

RE: McCulloch engine - what size?
 

You gott'a include a photo to help id it.

RE: McCulloch engine - what size?
 

I would, but all you can see is the head. All the rest is a conversion. Would just the head help? I was curious as to its displacement only. I can't find what McCulloch made in the 40 cc range. I fired it up today installed and it will turn a 20 x 8 at 7700 rpm so it's quite a bit more powerful than a G38. It is truly remarkably smooth all the way from idle to full throttle. It was converted by Tom Perry.

RE: McCulloch engine - what size?
 

Maybe Tom knows what size it is?

Enjoy,

Jim

RE: McCulloch engine - what size?
 

That's the point, he never measured it. He got the cylinders new complete with crank installed etc. and saw no reason to take them apart to measure them. If it ain't broke, don't fix it and I'm with him. I'm just curious is all.