How to adjust Holley regulator? | Team Chevelle 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. TURNING THE ADJUSTMENT SCREW ALL THE WAY IN WILL RESULT IN EXCESSIVE FUEL PRESSURE . Post in the forum instead. NPT Inlet Attachment: Fuel Pressure Regulator; Holley fuel pressure regulators are designed to precisely control the fuel pressure from the fuel pump to the carburetor. Does this need to be mounted upright or is it ok on its side? Show details From the manufacturer You could arrange them on a scale from naptha gas, gasoline, kerosene, stove oil, diesel fuel, light lubricating oil, heavy lubricating oil, grease, asphalt. Point and secure it into a clean container Inlet pressure of 7 psi limitation means your pump can not put out more than 7 psi to the regulator for it to properly operate. It does however produce an irritating fume that irritates the eyes and mucous membranes when burning in gasoline. Too much fuel pressure for a given needle and seat assembly can overload the needle and seat and may cause flooding or drivability problems. Going to check my VW bus fuel pump pressure. Google ethyl acetate and pay attention to it's "pure" boiling point, and remember IMCT is a blend of a white gas family of a petroleum distillate and ethyl acetate. Never had it act up while running, but since E10 fuel came along it is borderline getting started after hot shutdowns. Reviewed in the United States on January 15, 2021. Its a bypass arrangement with non return valves to prevent reverse flow and is operated by a switch for use in event of vapor lock. Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising. Most certainly also, should that be successful, I will then experiment with IMCT as well. I mix Industrial Maintenance Coating Thinner (IMCT) around 1 oz per gallon - which is basically a blend of petroleum distillate in the paint thinner / mineral spirits (once called also "white gas") family and ethyl acetate and not only does it cure vapor lock it increases octane because you can feel it in the power and acceleration. Then I got this good one, to try to get 1.5 PSI to the Kadrons. ESPECIALLY a 10% ethanol blend - once generically called the gasohol summer blend in that vapor system would really be a problem. Show details http://www.bp.com/liveassets/bp_internet/retail/retail_australia/STAGING/local_assets/downloads_pdfs/f/FN_modern_petro_vintage_engines.pdf, ,