Thanks for the quick respone lfinney,

I've played around with the pipe lenght a little. It doesn't seem to solve the problem. I think you may be on to something when talking about a possible air leak in the backplate or carb mount. I'm going to check that out. I'll let you know when I figure something out. I don't have a lot of time to work on it (and it's cold outside here) so it may be a couple weeks before I get a chance to check it out.
Ralph White