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Holley Billet Adjustable Regulator

Holley 12-840


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Holley Billet Adjustable Regulator $89.25
Billet Adjustable Regulator
  • Carbureted Applications
  • Adjustable 4.5-9 PSI
  • 3/8" NPT Ports

  • Holley 12-840 Details

    HP Series Regulators

  • Used in systems where a return line is not needed
  • Use with electric or mechanical pumps
  • Adjustable from 4.5-9 PSI for precise fuel pressure adjustments
  • One inlet, two outlets

  • Specifications:

    Mounting Bracket Included
    Fittings Included
    Boost/Vacuum Reference Port
    Gauge Port
    Inlet Attachment
    Female Threads
    Outlet Attachment
    Female Threads
    Pressure Range (psi)
    Sold individually
    Regulator Finish
    Black/Clear anodized
    Regulator Location
    Regulator Material
    Billet aluminum
    Regulator Style
    Inlet Size (in.)
    3/8 NPT
    Outlet Size (in.)
    3/8 NPT
    Outlet Quantity
    Inlet Quantity
    Manufacturer's Part Number:

    Holley Billet Fuel Pressure Regulators are part of a complete line of fuel system products. They are precision machined from 6061-T6 billet aluminum for strength and durability. They feature a black bright dip anodized body and a clear bright dip anodized top for corrosion resistance. Holley Billet Fuel Pressure Regulators are available in a variety of configurations.

    HP & Dominator Series
  • Demand and return style regulators available.
  • CNC machined from 6061-T6 billet aluminum for strength.
  • Black bright dip anodized body and a clear bright dip anodized top for corrosion resistance and good looks.
  • All regulators feature a 1/8" NPT gauge port.
  • Carbureted and EFI versions available.
  • All regulators include a mounting bracket for easy installation.

    Ultra HP & VR Series
  • Can support 3,000+ HP engine applications that require high flow fuel volumes.
  • EFI regulators are adjustable from 40-100 PSI base pressure.
  • Carbureted regulators are adjustable from 4 to 9 PSI base pressure.
  • Compatible with gasoline, methanol, and E85* (*requires draining and flushing after each race).
  • 1/8" NPT gauge port.
  • Designed for use with the Holley Ultra HP and Ultra Dominator Brushless in-line fuel pumps.
  • Can be referenced on a 1:1 ratio - includes a barb fitting and a -4 AN fitting for reference connection.
  • 2 port regulators feature a 10 AN O-ring inlet/outlet and return.
  • 4 port regulators feature a 10 AN O-ring inlet and return with (4) 8 AN O-ring outlets.

  • 12-840 - Holley Billet Fuel Pressure Regulators is rated 3.5 out of 5 by 2.
    Rated 2 out of 5 by from Disappointed!! Erratic pressure could get it to adjust properly and got stranded with the car??
    Date published: 2016-05-09
    • y_2018, m_7, d_20, h_5
    • bvseo_bulk, prod_bvrr, vn_bulk_2.0.8
    • cp_1, bvpage1
    • co_hasreviews, tv_1, tr_1
    • loc_en_US, sid_10001_10001_1617517, prod, sort_[SortEntry(order=RATING, direction=DESCENDING), SortEntry(order=SUBMISSION_TIME, direction=DESCENDING)]
    • clientName_jegs
    Items You Need
    Some parts are not legal for use in California or other states with similar laws / regulations