Phill I am a little slow responding. Email problems. I ran a Zenith carb on my 2180 VW conversion for 20 years after trying a number of different cabs in the beginning. It worked very well. I had rigged up a speedometer cable to control the mixture with a homemade U joint at the carb. The only problem I had in the beginning was I could not get it to idle properly. The problem was when I would turn the idle screw in far enough to get it to run it would be off the idle circuit and could not control the idle mixture with the idle mixture screw. After a call to the Zenith about my problem with my ? Air Boat? engine, I drilled about a 3/16 inch hole in the throttle plate, that enabled me to turn the idle screw back to where is was drawing fuel from the idle circuit at idle. It seems I also drilled out the main jet slightly, it was a little lean at full throttle at lower altitudes. I did not seem to have mixture problems at different throttle settings, but did not have a mixture meter, only a EGT on one cylinder. . The fuel distribution was excellent, even with my home made intake system. Most of the time I could lean the mixture until the engine would just quit, no stumbling. The Zenith will ice, so you need a good carb heat system. The only thing I did not like was you could not glance at the mixture knob and have a visual on the mixture position . On my new engine I have a Revflow with the tornado device behind the carb. I will give it a try. I have test run it and it seem to work OK. I like the vernier mixture control. If it gives me any grief I will build a manifold to use the Zenith again. I found a photo of a Zenith on a Q 2 where a system of gears attached to the main mixture needle allowed the use of a vernier control. I could email a photo to anybody interested. As I said, I have started my new engine for the first time, getting closer to flying it. As a side note, the barber pole stripes I put behind the fuel sight tube works well. Easy to see the fuel level. Roger Bulla [email protected]
