What is a good material to use us a "heat blocker" on the carb adapter. I making the twisting plate out of the aluminum I would like to know what is the good material to use as a gasket to limit the heat transfer from the engine to the carb.
Where can I buy it?

Thanks,

Any thick gasket material from the auto parts should suffice

Look for some that is at least 1/8" thick

Ideally you could make a spacer out of Delrin, which is a hard plastic substance. In a pinch, I have even made isolator manifolds out of wood, well coated with epoxy. Held up just fine...

AV8TOR

as far as gasket material, I have bought this rubber /cork material..it comes rolled up its about 10 inchs by 18 inchs, I cut gaskets out of it and punch holes for the openings, I have even used it for exhaust gaskets and it does a fair job...

I bought it at a local auto parts store ARNOLDS, it was only about 7 bucks a piece, I use it for other things like rubber washers and such,