ZDZ 40cc
Piston is different -
and there are pipes - also tuned cans available.
The ZDZ40 RE on a tuned can- is a excellent, powerful setup -
My suggestion - get the RE- a 40size KS tuned can-and a header kit for the ZDZ40 RE.
The new 40RE wWalbro carb is probably the nicest 40 setup I have seen-for compact installations.
Power is second to none.