It makes no discernible difference to power but if the conditions are sufficiently adverse it will still vapour lock and then you just have to wait until it cools. Holley 12-807 Fuel Pressure Regulator Diaphragm Repair Kit Like many others, I have been considering what to do recently. Somewhat of an inconvenience but that's why it's probably cheaper than other places selling the same part Great product from holley, but these do not come with the supplied tap that's suppose to be in box for the 2 machine screws that mount the regulator to the bracket. . Holly Fuel pressure regulator install | Jeep Enthusiast Forums Find an Automotive Service Professional Add some heavy ends. This Holley universal low pressure fuel regulator is factory-set to 2.7 PSI, but is fully adjustable from 1 to 4 PSI. Vapor lock was just a fact of life for the Fords. None of these contain lead and so should not damage a catalytic converter if you have one, HOWEVER too much IMCT will prolong the burn and may result in unburnt - STILL burning HOT gas being exhausted in the exhaust cycle. Log In / Register Order Status. This will ensure that the pump will not continue to operate after the engine is . Regards, Mike.