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GM Disc/Disc Proportioning Valve for 1/2-20, 9/16-18 Outlets

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Specs
Centerline of Holes:
2.69
Material Type:
Brass
Overall Height:
2.00
Overall Width:
1.08
Overall Length:
5.13
Sold in Quantity:
Kit
Finish:
Natural
Outlet Fitting:
Bottom front/Top front are 3/8"-24 IFF (to font brakes), Rearmost port is 9/16"-18 IFF (to rear brakes).
Garage Sale:
No
Notes
Includes hard lines with fittings, hardware, bracket, and brake light switch.
GM Disc/Disc Proportioning Valve for 1/2-20, 9/16-18 Outlets
Product Video
GM Disc/Disc Proportioning Valve for 1/2-20, 9/16-18 Outlets

Click image to enlarge

Watch the video below to learn more about the differences in brake lines, flare types and fittings you may want to consider before plumbing away on your current chassis project.

Details

Reviews

Q & A

What's in the Box

These proportioning valves are similar to what GM used on many cars in the 70's. They are non-adjustable and may require an adjustable valve in the rear brakes (if needed). Block incorporates metering (for front brakes) and proportioning (for rear brakes) into one unit. For use with four-wheel disc brake systems.

Includes hard lines to connect to a master cylinder with 1/2"-20 and 9/16"-18 outlets.

910-31352 Instructions (PDF)

Notes

Bottom Front Port: 3/8"-24 IFF threads - goes to one front brake
Top Front Port: 3/8"-24 IFF threads - goes to one front brake
Middle Top Port: 1/2"-20 IFF threads - comes from master cylinder
Rear Top Port: 7/16"-24 IFF threads - comes from the master cylinder
Rear Most Port: 9/16"-18 IFF threads - goes to rear brakes

Item Details

For M/C with 1/2"-20 and 9/16"-18 outlets.

Customer Reviews

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

RapidRonnie
Verified Purchaser
Plattsburg Mo.
Product Rating

Nice set up

February 24, 2011
Shouldnt have to write a reveiw for something that does what its supposed to do, but, so many things we buy dont work or fit like they should, its nice to find something that does what it should. I have installed several of these on customers cars and have not had any problems with them
Pros:
  • Easy To Install
  • Lightweight
Yes, I recommend this product.
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kbs10
florida
Product Rating

good product

April 08, 2010
had to make a trip to the parts store for a front port plug. my set up only used one port for the front.
Pros:
  • "oem" quailty
  • Easy bolt on
Yes, I recommend this product.
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Page 1 of 1
91031352

Product Q&A

4 questions : 5 answers

1 answers

does it have a plug in for a switch mine has one

dalej
St. Albans, WV, USA
June 19, 2014

does it have a plug in for a switch mine has one

Answers

June 19, 2014
EricM
This does have a switch and the pigtail for it as shown.
1 answers

will this fit a 1979 cadillac fleewood brougham with a 425 4 barrell with 4 wheel disc brakes if not do you have one I need a brake proportitioning valve for a 1979 cadillac fleedwood brougham with a 425. 4 barrel. I have 4wheel disc brakes

dalej
St. Albans, WV, USA
June 19, 2014

will this fit a 1979 cadillac fleewood brougham with a 425 4 barrell with 4 wheel disc brakes if not do you have one I need a brake proportitioning valve for a 1979 cadillac fleedwood brougham with a 425. 4 barrel. I have 4wheel disc brakes

Answers

June 19, 2014
EricM
This may be similar to the stock valve on your car but it may require some fabrication or changing of brake lines or fittings to install. Sorry I do not have a stock replacement valve for your application.
1 answers

when hooking this up, do you have to use both front outlets or can i use just a single front outlet? is there any advantage to using both front outlet

rcallella
January 06, 2014

when hooking this up, do you have to use both front outlets or can i use just a single front outlet? is there any advantage to using both front outlet

Answers

January 06, 2014
EricM
You can plumb it either way. There is not advantage either way other than ease of routing or number of fittings required.
2 answers

can i use this with front disc rear drums. i purchased your 7" booster and master cylinder 9106001 but when i got ready to install it looked at my reciept and its a disc disc and i have disc drum . will this still work whith this proportioning valve. and can i use 3/16 lines to front and 1/4 to rear. Thanks john

littlejohn
Gray Court, SC 29645, USA
December 10, 2012

can i use this with front disc rear drums. i purchased your 7" booster and master cylinder 9106001 but when i got ready to install it looked at my reciept and its a disc disc and i have disc drum . will this still work whith this proportioning valve. and can i use 3/16 lines to front and 1/4 to rear. Thanks john

Answers

March 04, 2013
mlswanny
Hi John, yes this proportioning valve will work, however a residual check valve will need to be installed in the rear line. Wilwood makes a very nice one part number 835-2601876. If you do not have the capabilities of installing this in the line, the prop valve you bought will need to be switched out to function properly! And yes you can use 3/16" front, 1/4" rear. Just keep in mind brake systems work best with pressure not volume, therefore by installing 3/16" on the rear system this will actually give you a higher, harder pedal. By reducing the size of the line, you reduce the volume and up the pressure. The same theory applies to the 1" bore master you purchased. If your pedal is to spongy or just wont stop the car get a master with a smaller bore. I usually try to run a 7/8 bore on most of my installs. All the way from a single piston caliper to 6 piston caliper...
December 10, 2012
Jason
We apologize for the confusion and the master cylinder you received under kit number 9106001 is a one inch bore and will work with disc/drum just fine. The proportioning valve will work with ¼” lines to the rear if so desired if your rod is plumbed that way. The larger line to the rear helps reduce the pressure to the rear to help insure even braking front to rear but is not required. We offer the needed reducer fitting if needed
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This adjustable proportioning block allows you to run lines from the master cylinder to the block and then to the appropriate wheels. What is neat about it is that it also contains the proportioning valve and brake light switch. This dramatically reduces the amount of fittings needed and potential leaks.

The adjustable proportioning valve regulates rear brake pressure, helping to maintain correct brake bias between front and rear brakes. It is designed for dual bowl master cylinders. The distribution block connects to the master cylinder and distributes brake fluid to all four wheels. An easy to turn handle with directional arrows makes it simple to either increase or decrease rear brake pressure.

The block accepts 3/16" brake lines and the inlets and outlets on this unit are 3/8"-24 inverted flare females.  It has two inlets from the master cylinder, two outlets to the front brakes and one outlet to the rear brakes.  It includes five stainless steel 3/16" fittings and wiring pigtail for rear brake light switch. Mounts to any convenient location. This is not a direct factory replacement for original blocks. Some line modifications may be necessary.

910-31358 Instructions (PDF)

Learn more about how adjustable proportioning valves work by reading our tech article. Brake System Selection.  

Wilwood 260-11179 Adjustable Proportioning Block
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This block has the proportioning valve built-in to the rear brake ports and a stop light switch built into the front brake ports. All ports are 3/8"-24 inverted flare female.

  • Compact design simplifies mounting, plumbing, & wiring
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  • Rear circuit has a single inlet and single outlet with the adjustable proportioning valve
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Proportioning Valve Installation Instructions (PDF)

Brake System Builder's Tip (Link)

Detailed Schematic of Proportioning Block 

Learn more about how adjustable proportioning valves work by reading our tech article. Brake System Selection.   

GM Disc/Disc Proportioning Valve for 3/8-24 Outlets
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These proportioning valves are similar to what GM used on many cars in the 70's. They are non-adjustable and may require an adjustable valve in the rear brakes (if needed). Block incorporates metering (for front brakes) and proportioning (for rear brakes) into one unit. For use with four-wheel disc brake systems.

Includes hard lines to connect to a master cylinder with 3/8"-24 outlets.

910-31366 Instructions (PDF)

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Brass adapters. Select from:

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