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Dual Diaphragm 7 Inch Stainless Brake Booster

SAME DAY SHIPPING! Order within the next 2 hours 38 minutes and receive same day shipping

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Specs
Centerline of Holes:
3.38
Material Type:
Stainless Steel
Sold in Quantity:
Each
Overall Thickness:
5.00
Finish:
Polished
Outside Diameter:
7.00
Bolt Hole Pattern:
3.38" x 3.38"
Rod Length:
4.00
Garage Sale:
No
Notes
Dual diaphragm booster. Pushrod is 3/8" fine thread.
Dual Diaphragm 7 Inch Stainless Brake Booster
Dual Diaphragm 7 Inch Stainless Brake Booster
Dual Diaphragm 7 Inch Stainless Brake Booster

Click image to enlarge

Details

Reviews

Q & A

What's in the Box

These show-quality polished stainless steel 7" boosters feature a dual diaphragm housing for use with heavier cars or pickups. Accepts most power brake master cylinders.

  • Pushrod stud is 3/8" fine thread
  • Master cylinder studs are two 3/8" coarse studs across from each other on 3-3/8" centers
  • Booster is 5" thick

Booster Tech Tip (GIF)

Learn more about selecting the proper brake booster for your vehicle by reading our tech article. Brake System Selection.  

Application

  • 5" thick from master cylinder mount face to firewall mount face
  • 4" long firewall mount face to end of pushrod
  • Four stud pattern is square pattern with 3-3/8" stud centers
  • Pushrod stud is 3/8" fine thread
  • Master cylinder studs are two studs across from each other on 3-3/8" centers

Specs

  • 5" thick from master cylinder mount face to firewall mount face
  • 4" long firewall mount face to end of pushrod
  • Four stud pattern is square pattern with 3-3/8" stud centers
  • Pushrod stud is 3/8" fine thread
  • Master cylinder studs are two studs across from each other on 3-3/8" centers

Customer Reviews

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

Stanley57
Verified Purchaser
Oxnard, CA, USA

the stainless look as good chrome.

March 22, 2015
The dual diaphragm 7 inch stainless brake booster fit perfect for my car. No more hard brake petal. The car now stop with little effort when I applied the brake. I'm very please on dual diaphragm 7 inch brake booster overall performance. Thank you!!!!
Yes, I recommend this product.
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Flatsmando
Verified Purchaser
Atlanta, GA, USA

Got the wrong part but it worked out bet

September 10, 2014
Ordered the wrong part for my master cylinder. Unable to locate correct booster so changed master. Very pleased with result. Good product and fast shipping. I now have a more common combination. The booster looks good too.
Yes, I recommend this product.
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Larry
Verified Purchaser
Rolla, Missouri 65401

Looks good fits

October 06, 2011
I haven`t finished the instillation but product has an excellent appearence and will look good in the engine compartment of my 1957 Chevrolet.
Yes, I recommend this product.
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Page 1 of 1

Product Q&A

6 questions : 6 answers

1 answers

Vacume problems How much vacume does this require? I have a 1970 Mustang with a 351 Cleveland that only provides 12 " ov vacume. I would like ot install a power brake booster, but have been running into problems with the amount of vacume that is required.

ADrian
Iowa
January 16, 2013

Vacume problems How much vacume does this require? I have a 1970 Mustang with a 351 Cleveland that only provides 12 " ov vacume. I would like ot install a power brake booster, but have been running into problems with the amount of vacume that is required.

Answers

January 16, 2013
Jason
Power brake boosters require 17" of vacuum or more to function properly. Smaller boosters may require up to 22" of vacuum to function proper.
1 answers

what booster or booster kit would be best to use with a 3000 lb +or- weight car with stick shift, suspended pedals of my own design and a clearence problem for the clutch master cylinder. thanks in advance AWA

AWA
Tucson AZ
February 18, 2012

what booster or booster kit would be best to use with a 3000 lb +or- weight car with stick shift, suspended pedals of my own design and a clearence problem for the clutch master cylinder. thanks in advance AWA

Answers

February 21, 2012
John
Part number 91031460 On a 3000 plus pound car we recommend a dual diaphragm power booster. Booster requirements are 18-20 inches of vacuum to achieve full power assist. For disc/drum a 1” bore master will suffice and for four wheel disc a 1 1/8” master is recommended when used with a booster.
1 answers

I have a chassis for a 1986 Chrylser Fifth Ave, discs in front, drum in back. Will this work on my car? Thanks

September 01, 2011

I have a chassis for a 1986 Chrylser Fifth Ave, discs in front, drum in back. Will this work on my car? Thanks

Answers

September 01, 2011
Zach
As far as this brake booster being capable of functioning correctly, yes this will work. However, this is a universal brake booster. The mounting arrangement may be different than the original master cylinder and or brake booster your car may have had originally. Here are the specs to help you determine if this will work for you: 5" thick from master cylinder mount face to firewall mount face, 4" long firewall mount face to end of pushrod, Four stud pattern is square pattern with 3-3/8" stud centers, Pushrod stud is 3/8" fine thread, Master cylinder studs are two studs across from each other on 3-3/8" centers
1 answers

I have a custom built car using the master cylinder from a 87 corvette,but the builder didnt design the system with a booster.If I have the room,will this booster work with the 87 corvette MC?

Jim
Indiana
June 14, 2011

I have a custom built car using the master cylinder from a 87 corvette,but the builder didnt design the system with a booster.If I have the room,will this booster work with the 87 corvette MC?

Answers

June 16, 2011
John
This booster requires a master cylinder designed to work with a booster or a master cylinder that is a combination manual or power brake master cylinder. Difference is the piston in the master cylinder. A regular hydraulic manual booster has a deep bore in the piston visible from the rear where the push rod enters and helps keep the push rod in place. A boosted master cylinder has a slight dish in the piston where the “spud” on the booster makes contact with the piston. There is always a slight gap between the small “spud” push rod and the piston allowing the piston to return all the way when the pedal is released. The internals on the master cylinders is basically the same and the Corvette style master cylinders we offer are adaptable to either braking system. Included in the box is a dished cylinder or adapter that slides into the deep bore of the master cylinder piston changing it to a slight dish and from a manual to a power master cylinder.
1 answers

I have one of these boosters and a master cylinder with the shallow hole in the back. After doing some research I find that there should be no more than 1/32" clearance between the pushrod on the booster and the hole in the rear of the master. I have abou

Tim
Victoria B.C.
April 10, 2011

I have one of these boosters and a master cylinder with the shallow hole in the back. After doing some research I find that there should be no more than 1/32" clearance between the pushrod on the booster and the hole in the rear of the master. I have abou

Answers

April 18, 2011
Jack
The pushrod on the booster is adjustable so you should be able to adjust that to take up the clearance.
1 answers

Can I use this booster with a wilwood aluminum master cylinder?

Brett
TO
September 24, 2011

Can I use this booster with a wilwood aluminum master cylinder?

Answers

September 27, 2011
John
This booster can be mated to any master cylinder with the common two bolt horizontal mounting pattern designed to work with power brakes. Wilwood master cylinder number 8352608555 or 556 can be used as the master cylinder is designed to work with manual brakes as it comes or by inserting the slug into the piston bore it reduces the bore to a slight dish to match up with the booster. Simply verify the master cylinder can be used with a power brake application.
Page 1 of 1

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These show-quality chrome 7" diameter boosters have a single diaphragm for use with lightweight cars. Accepts most power brake master cylinders.

  • Pushrod stud is 3/8" fine thread
  • Master cylinder studs are two 3/8" coarse studs across from each other on 3-3/8" centers
  • Booster is 3-3/4" thick

Booster Tech Tip (GIF)

Learn more about selecting the proper brake booster for your vehicle by reading our tech article. Brake System Selection.  

Single Diaphragm Chrome Booster Master Cylinder Combo
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These show-quality brake combos come with a 7" single diaphragm chrome plated steel booster and a chrome master cylinder with a 1" bore and dual 3/8"-24 IFF outlets (on both sides). Includes plugs for unused ports.

Suitable for use with front disc/rear drum brake systems.

Booster Tech Tip (GIF)

Brake System Builder's Tip (Link)

Learn more about selecting the proper master cylinder for your vehicle by reading our tech article. Brake System Selection

Adjustable Proportioning Blocks With Brake Light Switch
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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.  

Chrome Power Brakes Master Cylinder
(Part #91031446)
                        

This beautiful chrome master cylinder is highly versitile featuring outlets on both sides and a 1" bore. Has 3/8"-24 IFF outlets (includes 2 plugs for unused ports).

For use with power brake boosters - NOT for use with manual brake systems. Suitable for use with front disc/rear drum brake systems.

Brake System Builder's Tip (Link)

Learn more about selecting the proper master cylinder for your vehicle by reading our tech article. Brake System Selection

Universal Frame Rail Power Brake Pedal Mount
(Part #91631987)
                        
  • Mounting bracket sets off frame rail 2 inches for clearance 
  • Push rod center is 4 inches from frame rail mounting bracket
  • Uses standard GM booster with 4 bolt mounting holes, 3-3/8" centers
  • 10-1/2" tall brake pedal arm with clevis and push rod
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Wilwood 261-13270 Aluminum Tandem Master Cylinder Kit with Bracket and Valve
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These Aluminum Tandem Chamber Master Cylinder kit from Wilwood comes with a Combination Proportioning Valve, mounting bracket, fluid tubes and mounting hardware. The Tandem Master Cylinder represents the latest in refinements in brake pressure actuation and fluid control. The slotted flange mounting makes it a simple bolt on for many OE mounts including the popular Chrysler, Corvette, GM, and Ford Mustang bolt patterns and is compatible with manual or power brake system applications. Master cylinders are available with a 1-1/8” bore size and they come in your choice of standard, ball burnished, or black E-coat finishes.

The combination proportioning valve substantially simplifies wiring and brake proportioning adjustments on vehicles with custom brake systems. The combination block maintains full isolation between front and rear fluid circuits and is specifically designed to accompany the Tandem Chamber Master Cylinder. The combo valve and bracket are black E-coated for a performance look and long lasting durability. Stainless steel fluid tubes are precision bent with preinstalled stainless tube nuts for a simple bolt-on installation between the Combination Proportioning Valve and the Wilwood Tandem Master Cylinder. Stainless steel button head fasteners thread into the bracket for a simple installation and years of durable, rust-free performance. Simply connect the fluid lines, bleed the system, and you're finished.

  • Bore size: 1-1/8"
  • 1.1" stroke
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  • Fit size 1: 3/8"-24 IF or 1/2"-20 IF
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  • Integral res type
  • Aluminum
  • Choose from standard, ball burnished, or black E-coat finish

Wilwood Tandem Master Cylinder Kit Product Data Sheet (PDF)

New Product Release (PDF) 

Universal Power/Manual Master Cylinder, 1 Inch Bore, Corvette-Style
(Part #91031445)
                        

These high-tech corvette-style master cylinders were designed using OE specifications and 100% tested.  They have a 1" bore and are suited for disc/drum combinations. Each master cylinder is ported on both the left and right sides, allowing for installation in many different applications. This exclusive design features a mating flange that works with applications requiring 3-1/8” through 3-3/8” bolt patterns.  These master cylinders will work with manual or power brake systems and can be quickly changed with the included adapter pin to plug the deep well.  The wide body and low profile gives this master cylinder the clearance you need when installing in tight areas and yet it maintains a large volume of fluid necessary for 2 and 4 wheel disc brake applications.

  • 1" bore
  • 3/8"-24 IFF outlet ports on both sides
  • Plugs are included for the unused ports
  • Mount spacing is 3-3/8" on center
  • Works with power or manual brake systems
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Brake System Builders Tip (Link)

Learn more about selecting the proper master cylinder for your vehicle by reading our tech article. Brake System Selection. 

Item Details

Dual reservoir master cylinder
1" bore, Shallow Hole, Dual Port, Plain
Power/Manual Master Cylinder, 1-1/8 Inch Bore
(Part #91031440)
                        

Corvette-style master cylinder has a 1-1/8" bore and is suited for disc/drum combinations. Features dual outlets so the plumbing can come out either side of the master cylinder. These master cylinders will work with manual or power brake systems. They come with a deep-well piston for manual brakes and an adapter to fill the deep well for use with a power booster.

  • 3/8"-24 IFF outlet ports
  • Plugs are included for the unused ports
  • Mount spacing is 3-3/8" on center
  • Works with power or manual brake systems

Brake System Builder's Tip (Link)

Note: Customers intending to use this as a manual brake pedal assembly should note that the pushrod and boot are not included.

Learn more about selecting the proper master cylinder for your vehicle by reading our tech article. Brake System Selection