Log In / Register Order Status. Some parts are not legal for use in California or other states with similar regulations. I have the one I have set up in a deadhead setup. This part is Backordered. ). The Holley 12-804 fuel pressure regulator is adjustable from 1-4 psi. For the best experience please upgrade or visit the site on another browser. $5 Off Your $100 Mobile App Purchase . Inlet from fuel pump is at bottom. Can anyone speak to the validity of this or is anyone currently using an additive for this? Holley recommends applying PTFE paste to the NPT thread of the fittings before installation on these applications. Neither the Holley instructions nor anywhere I can find says what the maximum inlet PSI should be allowed to the regulator - but I was told it was 16 psi and one other spot on the web says something similar. Click here to find a Holley HOL 12-804 12-804 Fuel Pressure Regulator Brand: Holley 436 ratings | 33 answered questions Amazon's Choice in Automotive Replacement Fuel Injection Pressure Regulators by Holley $4119 FREE Returns Adjustable fuel regulation from 1 to 4 psi .220" (7/32") restriction 3/8" NPT ports ( 1 in, 2 out) Mounting bracket included Pre-set at 2.8 PSI Open the unit and check the spring color, Reviewed in the United States on April 9, 2018. Discussion in 'The Hokey Ass Message Board' started by oldrelics, Oct 12, 2010. By 1913 it was the other way around. holley blue fuelpump pressure erratic. Another thing you can do is wire the fuel pump to be hot in run and start through an oil pressure switch - so if the motor shuts off or looses oil pressure the fuel pump shuts off too. TURNING THE ADJUSTMENT SCREW ALL THE WAY IN WILL RESULT IN EXCESSIVE FUEL PRESSURE . Loosening the regulator locknut and turning the adjustment screw clockwise increases the pressure. I feel lucky that this did not damage my generator because at one point I saw 30lbs of pressure while trying to start the generator. In a deadhead design the fuel comes into the regulator from the bottom past a check ball which is held open by a pin on the diaphragm. There was a problem adding this item to Cart. Please use a different way to share. Does it come with the hose fittings or to be bought separately? In the fuel use map in the Exxon or Mobil gasoline websites, there are a few places where the Reid Vapor Pressure spec is varied from other fuels. Many thanks for taking the time to clarify this interesting subject . Use with standard pump only -not recommended for maximum pressure pumps. Most certainly also, should that be successful, I will then experiment with IMCT as well. There are two kinds and they look the same. Installation was made more complicated by the absence of a port for a pressure gauge, which means Rusty, thanks so much for this information. Interesting theory. My plan was to install a fuel pressure regulator on the line going to the generator so that the bypass valve needs less fine tuning to maintain the same pressure in all temperatures. Holley 12-804 Fuel Pressure Regulator Installation Instructions . A vapor lock condition would be caused. For cars that require 4.5 to 9 PSI, the Holley 12-803 is the right model. . But the heavier elements will raise the boiling point of the mixture. Error posting question. Regards, Mike. As you can see from what it replaces - it is "hot" solvent - but not quite as hot as acetone in its ability to dissolve other things. use a 1/16 - 1/8" restrictor in the end of your fuel line to see if you can set the pressure then. The peak was reached in the sixties when heavily leaded gas of over 100 octane was available. Second, you adjust this regulator by turning the hex screw on top - does anyone happen to know how many pounds one or more full turns would produce etc? Unfortunately, this fuel pressure regulator does not even come close to regulating the pressure and keeping the pressure down. This item cannot be shipped to your selected delivery location. At first it seemed fine, set it to 1.5 PSI and away we go. I put it . Reviewed in the United States on September 4, 2017. (that is this one in the image below) The adjustment spring under the adjustment screw is pushing down on the diaphragm holding the ball off it's . Otherwise it's good. 9 really is max. The 12-803 4.5-9 psi spring is plain, (just the gold colored plating) the spring is accessible and replacable The cheap dial units are terrible. All Holley regulators are pre-set at the factory so there is no guesswork when first installing the regulator. From that time on octane ratings slowly rose, helped by the addition of more and more tetraethyl lead. With this set up, pressures throughout system varies only very slightly from atmospheric, lower up to the vacuum tank and higher in the gravity feed from the vacuum tank to the carburettor. Kerosene diesel fuel or stove oil will work. Show details From the manufacturer and a rotary click style one here on the shelf pete, you are welcome to borrow them to troubleshoot your problem.. let me Know. Right & left, Customer Reviews, including Product Star Ratings help customers to learn more about the product and decide whether it is the right product for them.Learn more how customers reviews work on Amazon. Q: Holley Bracket Secondary Adjusting Lever Kit Steel Gold Iridited Holley 4150.