ORIGINAL: Hobbsy
http://www.webra-austria.at/download/en/motor.pdf
Scroll down to the DynaMix carb and item 5 says the DynaMix carb will operate with muffler pressure or a pump, just like any other engine. For anybody with Webra engines tht page is well worth printing. Nobody caught it but the Webra .50 running as a Diesel is wearing an MVVS 7mm carb.
The reason Webra never took off in this country was the lack of instructions written clearly in English, plus a lack of explanation regarding the high compression ratio that would lead to preignition and overheating if conventional US nitro amounts were used without reducing the compression. Why Webra put up with this kind of behavior from their US distributors has always puzzled me. Webra engines are among the best on the planet, as far as I'm concerned.
Ed Cregger