Bill:

What I was trying to do with the last post was to see if you, W8 and I could agree on the 3 things I stated there. I tried to distill information from a number of sources including this thread: http://www.rcuniverse.com/forum/m_26.../tm.htm#267362
I think you have made additional points, but I still wonder if you agree with me.

One of the conclusions I came to was that the words "regulator" (ala Cline) and "regulation" as pertains to the VP20 and 30, while they suggest simularity, hide significant differences in terms of, among other things, the type of carburetor which can successfully be used.

I think that is part of the problem with the Webra/UAV 120s with the TNII carb when a pump is added. It may be a "regulating" pump, but it still delivers a pressure at the carb, that is outside the design parameters of that carb.

I have used the Cline "regulator", with crankcase pressure and a closed system, with the 120 (without pump) with the TNII with no problem, indeed it made the engine run more reliably. But, I believe that this experience outline in this thread suggests that the TNII does not work well with the pump that comes with those engines. I suppose the proof will be in the pudding, when I try the Promix II.

If I am correct, and given the email from Webra Austria mentioned above, I do not understand why Webra distributes pumped Webra 120s with the TNII carb. They sell another version of the 120, with pump, with the Promix II carb, which they indicated is the carb to use with a pump.