Its an SC. Also known as "Super Custom" glow engines.

South Aero Engine Company makes them in Zhuzhou Hunan China.

The motors are also sold as ASP, SY, and under other names. Clever marketing from the chinese - why restrict yourself to one distributor for your product when you can have 2 or 3?

I have owned three or four SC / ASP's in the past. I then developed a taste for the expensive ...

SC's are popular budget motors in the UK and Australia. They seem to be OK although they are not up to Super Tigre, OS, Irvine etc in finish. They have good piston / liner fits in the ABC variants with true chrome plating that doesn't seem to peel. But carbs on these motors can be hit and miss. Many put OS carbs on them if they get a poor carb on theirs. The cranskhafts are also not surface hardened. Good news - can be straightened if bent a little out of true in a hard landing. Bad news - they can fail if under severe stress. I broke 2 crankshafts when I dieselised my SC 46 and 32. I went back to glow operation for these motors after that.

I still have my old SC 32. I believe the quality of these engines is improving all of the time. The latest run are now copying all aspects of the OS "FX" design (ie semi-square heads, rnv, etc).

I think J Perkins Distributes them un the UK. I don't have a website for SC but if you want to look at them go to www.justengines.org.unseen and click on the ASP engines button. They are exactly the same motor as the SC's.