I've come across a possibility. I found, in a box of old parts at a hobby shop, a sleeve and piston for a .12 Force engine which shares the same dimensions (almost) with the O.S. CZ-2 I'm trying to get running. The guy at the hobby shop was kind enough to let me take it for free.
I was hoping all I would need to do would be slip the new piston into the old sleeve. But the new piston slides right through the old sleeve. So my next option is to replace both the sleeve and piston, but, even though the ports are oriented in the right directions, there are differences in the space they take up vertically.
There are three differences actually:
1) the new sleeve itself is 1.5mm shorter than the original.
2) the transfer ports are much shorter and don't connect to the channels in the engine block. So they need to be cut larger to match the old ones.
3) The boost port is also shorter, although I'm not sure this is critical. What might be critical is the omission of a hole in the piston to match the boost port orientation.
Do you think there is a chance this piston-sleeve can be modified to run in the CZ-2 engine?
And, if so, do you think it can be done with simple tools? I have a Dremel tool which I have seen used on YouTube to modify ports in nitro engines.
