This Holley universal low pressure fuel regulator is factory-set to 2.7 PSI, but is fully adjustable from 1 to 4 PSI. Unfortunately, this fuel pressure regulator does not even come close to regulating the pressure and keeping the pressure down. To minimize exposure, avoid breathing exhaust, do not idle the engine except as necessary, service your vehicle in a well-ventilated area and wear gloves or wash your hands frequently when servicing your vehicle. Copyright 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. 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. A larger tank might need two quarts. 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? In fact I can completely remove the adjusting screw and it still does not go down to 3psi. Gasoline vaporizes according to fuel system pressure. Thinking Kerosene is probably the way I will go at this point. For over a century Holley has driven the cutting edge of fuel-system design. Could you explain a little more about how you would run the bypass? The carb should not flood even with the pump running unless it is putting out enough pressure to over come the float bowl shut off mannerism mechanism of the carb. Adjustable fuel regulation from 1 to 4 psi, Holley 12-804 Reg, Fuel Press 1-4 Psi Pol. We currently do not have an estimate when this item will ship. To ensure this condition, the installation of a Holley 12-810 oil pressure safety switch is recommended Holley Manufacturer Part Number 12-804 Manufacturer Holley Assembled Product Dimensions (L x W x H) 3.50 x 3.50 x 2.50 Inches Warranty Warranty information 90 DAY REPLACEMENT IF DEFECTIVE Warnings Warning Text proposition 65 reasons:titanium dioxide, other chemicals WARNING - California Proposition 65 None Report incorrect product information . [endif]--> http://www.bp.com/liveassets/bp_internet/retail/retail_australia/STAGING/local_assets/downloads_pdfs/f/FN_modern_petro_vintage_engines.pdf, ,