I was talkign with the LHS last night, and the guy said that basically nitro cars will have the rich when full, lean when empty problem - he claimed no matter what.

I have been checking around in the RB Forums as well, and lots of guys with the Rb's are having issues that I guess are more evident somehow, I dunno. I was running mine last night and when I would bring it in for fuel it would be idling pretty high (lean), and I would just pour the fuel in and let the lid shut and the motor would idle right down as it went back rich. It was pretty amazing.

And then it didn't run as well for a while. So I definetely have the problem.

I guess my question is: All these guys that claim to have "fixed" the problem (and they all do it different ways which makes me skeptical), have they really fixed it, or is it in their head? If what the LHS said is true, then it "can't" be fixed.

There were some guys on the RB forum talking about running a piece of fuel tube from the little pressure hole under the cap, down into the bottom of the tank. They claimed that helped. One guy said he made his pressure line 8" long, and used a small fuel fitler in line with the guts taken out - I guess as a sort of pressure tank to help "smooth the pulses from the tight pinch of the RB."

So, is it that a motor that flows more exhaust needs a bigger tank to help mediate the pressure difference between full and empty tank? Is that what you're getting at?