I have a converted one that was a 28 with a broken cylinder that someone gave me. I bought a hopped up 32 piston and cylinder from a guy on here and made a 32 out of it. It runs real good. 18-8 @ 7500.

This picture is from the Carr Precision website. They sell conversions.

I have two converted and they have C-H iginitions on them.

I used a 1/2" carb on both engines.