I really don't want to get into an online debate here. All I can tell you is that the instructions that came with my VP-30 (1 1/2 yr old) clearly states do not run muffler pressure to the tank. I also called the nice folks at Perry and discussed this with them. They said do not run the muffler pressure, and explained why. I have been running the VP-30 on my ST 2300 for over a year with the clunk 16 inches behind and 2 inches below the carburetor spray bar. Tank is vented to the outside air. Performance is outstanding at all throttle settings, and airplane attitudes.

For your own peace of mind I suggest you call the folks at Perry Pumps and ask their advice. 630-858-3160. They are very nice and knowledgeable and will be more than glad to help you and answer your questions.

I'm outta here