holley 12 804 adjustment

Reviewed in the United States on September 4, 2017. The Holley Fuel Pressure Regulator (Part No. Check the status of your . NOTE: P/Ns 12-841, 12-842, & 12-879 utilize 3/8" NPT inlets and outlets. Discussion in 'The Hokey Ass Message Board' started by striper, Aug 12, 2009. 3/8Inch Npt Ports 1 Inch 2 Out. This ensures that it's set too low. By the way, I had an excellent service from this seller (5 stars!). This will ensure that the pump will not continue to operate after the engine is . So this thread has been a great find for me particularly at this time. Mr. Gasket 1561 Fuel Pressure Gauge 1.500 in. Add some heavy ends. Purchased the regulator from Baxter, unit arrived in 4 days.. I have just this Spring started taking temp. It's unlikely that anything's stuck. http://www.jalopyjournal.com/forum/showthread.php?t=386155, Kingman, Arizona - The place on the way to other p, http://www.holley.com/types/Fuel%20Pressure%20Regulators%20-%20Carbureted.asp, (You must log in or sign up to reply here. Please choose a different delivery location. bowls after each run, just to see exactly at what temperature the problems become apparent. couple more questions, Rusty, what exactly are "heavy ends"? It IS variable and a result of the various fuel blend components. The '54 Bentley already has an electric SU pump back near the tank, and it's low pressure output is just about right for the two SU H6 type carbs. Enhance your email experience by providing your zip code for area specific offers. Decrease pressure by turning the adjustment screw counter-clockwise. Copyright 2023, Antique Automobile Club of America. Most certainly also, should that be successful, I will then experiment with IMCT as well. I can only say acetone will lower flash point (light easier) but also lower auto-ignition temperature and thus create knock into too much of a quantity - while a very little bit will raise octane but not lower auto-ignition - so if you go TOO low with kerosene or diesel you can bring back some kick to the fuel with SMALL amounts of acetone. It's a diaphram with a spring. The two will be very close to the same just as would Water and Anti-Freeze boiled in an open pot. Sign up for a new account in our community. The Holley 12-840 fuel pressure regulator features 3/8" NPT in/out ports. I take this to mean that the separate boiling points of the constituents occur at atmospheric pressure but at higher pressure the resulting mix has a single boiling point. You set it to the exact fuel pressure you want. MFG. Click here to find a The issue is simple that one is seeking to "re-blend" their own gasoline from one already sold. 2023 Holley Performance Products, Inc. All Rights Reserved. The regulator is a Holley 12-804, I was told it went down to 1 psi and I have a stock mechanical fuel pump. It feeds fuel directly from the tank to the carburettor. None of them worked. What one is after is new "liquid" fuel which vaporizes easily in open air, lights easily and has a rapid flame spread but NOT a hot explosive one, and burns easily and completely under one atmosphere of pressure - what we call 14.7 to 1 - BUT - and this is most important; does not auto-ignite at a low temperature and WAITS to be lit by the spark after being compressed in the cylinder. YES the boiling point of gasoline can be raised (or lowered) by an additive - depending on what it is - as can the autoignition temperature which will increase "knock" - using the right additive for the fuel you just bought and put in your tank is the trick and it is always going to be hit and miss - depending on what refinery produced the gasoline in the first place. Exclusive, high-quality Global Featured Holley Transmission Kickdown Cable Bracket 20-121; Gold Zinc Steel for 700R4 . Average for the last 12 months. Too much fuel pressure for a given needle and seat assembly can overload the needle and seat and may cause flooding or drivability problems. (see reg-setp.pdf), This is the same design as a Holley 12-803 or 804 knock off, so I looked up Holley's instructions. Mounting Bracket Included. Q: They use gravity feed from vacuum tank mounted under the hood and directly over the exhaust manifold. One needs to have studied Chemistry as I have to actually know how this works. I commented that it was already vented by the clearance around where the float needle projects through the top but he advised that this was not enough and the vent needed to be at least a 1/4" tube and that he could see it venting vapor. . This product is made of high-quality materials to serve you for years to come. 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. ESPECIALLY a 10% ethanol blend - once generically called the gasohol summer blend in that vapor system would really be a problem. I'm suggesting to raise the boiling point by adding heavier or oilier substances such as kerosene. Then I got this good one, to try to get 1.5 PSI to the Kadrons. Once the fuel fills up the float bowls in the carburetor and the needles and seats shut, it starts to build pressure, pushing the diaphragm against the adjustment spring under the adjustment screw and allowing the ball to go "up" against the seat, effectively shutting off fuel flow to the carb. IMCT is found in the paint isle of any hardware or home improvement store usually in quart or gallon cans. 12-804 12-500 Low-Pressure Fuel Regulator (std. Some of these items ship sooner than the others. store I wanted to upload the map, but at 2.73mb, it was too big. For more information go to www.P65Warnings.ca.gov/passenger-vehicle, WARNING: This product can expose you to chemicals including Styrene which is known to the State of California to cause cancer. One must understand the chemical reactions and interactions of blending other hydrocarbons into what we call gasoline and then still have it able to have the same properties desired of the product called gasoline. 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? Thinking Kerosene is probably the way I will go at this point. Take a look at the article below. All petroleum distillates have different chemical properties which change depending on what you mix them with. Will changing the orientation change the preset pressure setting (checkball falling instead of raising)? te4cmCbGnt]&~`N@RPyBTa$=~fo:/T 92YE)3Uofo4Ou].-zowDt*ae^qf9z/?. use a 1/16 - 1/8" restrictor in the end of your fuel line to see if you can set the pressure then. I had hoped that the cooler fuel from the electric pump would solve the problem but it did not. Unfortunately, this fuel pressure regulator does not even come close to regulating the pressure and keeping the pressure down. The reg takes 3/8" fittings and the gauge takes 1/8" fittings. Usually, just runs really lean for a couple of minutes, and will not go above idle until fresh fuel finally clears through. Driving on a warm day in heavy stop start traffic it started vapor locking on a climb - using 10% ethanol fuel with no additive . 4.25 out of 5 stars. I have adjusted a 6-9 lbs pump down. This product is universal and applies to all vehicles. Please use a different way to share. Great feedback from a knowledgeable group, guys! This went on until they developed the cracking process which allowed more flexibility in what they got out of the crude. Profile Page . The reliable, albiet slower, stovebolts never suffered vapor lock because the fuel pump and lines were up front in the airstream of the engine fan. I am intrigued by you statement, "Once these chemicals are blended - the over-all resulting chemical properties - especially boiling point under pressure is changed - they are NO LONGER SEPARATE boiling points in play.". The following vehicles are considered Emissions Controlled Vehicles: *Free Shipping & Handling only offered to the contiguous US on orders over $100, excludes clearance parts and oversized packages. ***The inlet pressure limitation is 7 psi. TURNING THE ADJUSTMENT SCREW ALL THE WAY IN WILL RESULT IN EXCESSIVE FUEL PRESSURE . Each Holley fuel pressure regulator is fully adjustable so regulating the fuel pressure to your engines needs is a simple task. Designed using state-of-the-art technology and with customers in mind. Use with standard pump only -not recommended for maximum pressure pumps. The Holley 12-804 fuel pressure regulator is adjustable from 1-4 psi. Why does this occur only under increased pressure? I have heard true lead (LeadMax2000 or simillar) may do this as well? Enhancements you chose aren't available for this seller. We are sorry. Free shipping for many products! Can i install a fuel pressure guage on the unit itself? This satin finish regulator feature 3/8 pipe thread . But, . [endif]-->