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Holley 12-804 Adjustable Fuel Pressure Regulator, 1-4 PSI

Specs
Material Type:
Aluminum
Sold in Quantity:
Each
Finish:
Chrome
Thread Pitch:
3/8" NPT
Overall Height:
1.91
Notes
This part is flash chromed.
Holley 12-804 Adjustable Fuel Pressure Regulator, 1-4 PSI

Click image to enlarge

Details

Reviews (9)

Q & A (4)

What's in the Box

Info

This Holley universal low pressure fuel regulator is factory-set to 2.7 PSI, but is fully adjustable from 1 to 4 PSI. Use with standard pump only - not recommended for maximum pressure pumps. Fuel pressure regulator includes mounting bracket.

Regulator has a 3/8" NPT tapped fuel pressure gauge port and requires reducer 617-6157 to install the gauge. Fuel pump regulator has 3/8" NPT inlet/outlet ports.

427-12804 Instructions (PDF)

 

Bracket Measurements:

  • 2-1/2" wide
  • 1-1/2" tall and deep
  • 1-3/4" hole spacing to mount the regulator to the bracket
  • Chrome steel construction

Customer Reviews

Rated 4.7 out of 5 by 9 reviewers.
RATING BREAKDOWN
9 reviews
5 Stars
7
4 Stars
1
3 Stars
1
2 Stars
0
1 Star
0
RECOMMEND THIS PRODUCT:

Ken
Verified Purchaser
Verified Reviewer
vermont

not the best choice for DCOE Webers

July 23, 2016
not best for use with DCOE Webbers
Pros:
  • Well Made Like All Holley
No, I would not recommend this product.
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Fred V
Verified Purchaser
Verified Reviewer
Pensacola, Fl.

Good operating regulator

April 06, 2016
I'm using this to regulate a 6PSI pump feeding motorcycle carbs. I previously had one of those round jobs with the round dial on top. Piece of junk; just a flow regulator. The Holley works. I hooked a pressure gauge to it first to test it and it does the job with good flow. Fred V
Yes, I recommend this product.
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Terry
Verified Purchaser
Olean NY

Fixed my carb problem

October 19, 2015
I have been building cars for 40 years and did not know this regulator existed.It fixed the headache I have had with the Speedway 3 reproduction stromberg carb setup.This should be mandatory with this intake/carb combo.
Yes, I recommend this product.
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Roy Boy
Verified Purchaser
Verified Reviewer
St. Charles, mo63304

If needed I would purchase this again

September 09, 2015
Needed this 1-4 psi regulator due to carb setup, Could not have more than 4psi with Blower and crbbs
Pros:
  • Works Great
  • Had To Have This Item
Yes, I recommend this product.
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Rat-Z
Verified Purchaser
Verified Reviewer
Springfield, MO

great product

July 23, 2015
I use this in my Datsun 240z, with dual SU carburetors. Works wonders with the upgraded fuel pump. Holley does not provide the correct barbed fitting sizes.
Pros:
  • Easy Installation
  • Extremely Simple
Cons:
  • Fitting Info Is Wrong
Yes, I recommend this product.
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Willys53
Verified Purchaser
Chadron, NE

Just what I needed!

May 18, 2015
I struggled with the carb on my old Willys jeep pickup for a year after I replaced all the old stuff. It made no sense, was running before I replaced everything, would not run afterwards--until I put on the simple, easy-to-install (did I mention chrome?) regulator. Now she's ready for the parades again!
Pros:
  • Looks Great Works Great
Yes, I recommend this product.
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Nitro286
Verified Purchaser
Austin, TX, USA

Perfect for Model 97 carbs and it's a na

August 22, 2014
Great product for Flathead Fords with model 97 carbs. They require low pressure, 3 psi or less, and this pump will take care of 3 x 2's.
Yes, I recommend this product.
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judo
Verified Purchaser
rosenberg ,texas

I order a lot of differant items from yo

June 23, 2014
Your products are priced right and the deliverry time is excellent.
Yes, I recommend this product.
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Rich
Verified Purchaser
Omaha, NE

easy to install and adjust

September 02, 2011
good quality product
Yes, I recommend this product.
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Page 1 of 1

Product Q&A

4 questions : 4 answers

1 answers

can this be used with a holley mechanical fuel pump producing 8 p.s.I. pressure

streetrodman
Indiana, USA
March 06, 2015

can this be used with a holley mechanical fuel pump producing 8 p.s.I. pressure

Answers

March 06, 2015
EricM
Running the Holley regulator 12-804 and cutting the pressure more than half on your mechanical pump could cause problems and cavitation in the pump. We would suggest running a return line from the regulator as illustrated in the instructions. You can view the instructions here: http://static.speedwaymotors.com/pdf/42712804.pdf
1 answers

does this regulator come with fittings for 5/16 fuel line?

banksy
Moore, OK, USA
April 26, 2014

does this regulator come with fittings for 5/16 fuel line?

Answers

April 28, 2014
EricM
No this does not come with any fittings or adapters. You would need hose barbs to adapt to 5/16" rubber hose such as 91011774
1 answers

Does the bracket come with this regulator to attach to firewall?

40MercFlathead
Missoula, Montana
December 04, 2011

Does the bracket come with this regulator to attach to firewall?

Answers

December 05, 2011
Jason
Yes, this includes a mounting bracket
1 answers

Do you recommend a specific pressure gauge to work with this setup?

Danny
Costa Mesa, CA
May 31, 2015

Do you recommend a specific pressure gauge to work with this setup?

Answers

June 01, 2015
Eric
Expert
Any fuel pressure gauge can be used with this regulator as long as it has a 0 to 5 psi range as a minimum. Most low pressure fuel pressure gauges are 0 to 15 psi. An engine mounted gauge such as 91011851 can be connected to one of the outlets of this regulator if only using one outlet to the carb. You would need reducer 6176157 to adapt the 3/8" NPT of the regulator down to the 1/8" NPT of that fuel pressure gauge.
Page 1 of 1

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