Added a second shim under each needle this evening took it on a test run. I'd say it seemed to be about an 80% improvement. TBS needles due in early next week. I'll get back with the results after they go in. BTW, I discovered by sucking and blowing on the bottom of the gas cap and also the vent hose from the bottom of the tank, air goes only one way, outside to inside the tank through the cap and inside the tank to the outside through the vent hose.