I don't know if this is what you are looking for or not, but it is one I was considering when I was playing with my gas four stroke. I got mine to run pretty good on a butterfly carb, but was thinking of buying this one. I subsequently sold the airplane with the engine, so the experimenting never went any further. If this carb is not specifically for a four stroke, you could probably make it work with nothing more than the addition of a small return spring under the fuel pump diaphram. I had to add one to my butterfly carb to make it work on the four stroke as well. (I just used the spring out of the carb that came with the engine originally.)

Anyway, check it out: http://www.davesmotors.com/s.nl/c.88...t.A/id.4132/.f

AV8TOR