I have no issues with the 8.5 psi pump the part number is 4862 you might be right on the flow for the part you mentioned there is another version that only flows 80gph. Check it at Mancini. I have no issues with the 8.5 psi not blowing past the seat 6 pack runs strong with no issues. Real world...if there was an issue all you need is a reg after the pump set it to 7.5 psi. A good six pack will run out of steam with the lower psi IMO.