Product Summary

Universal Fit, Firewall Position, Tandem Outlet Count

  • GM-style aluminum master cylinder provides a weight savings and longer service life
  • Has 2 mounting holes on a 3-1/4" center for 3/8" or 10mm bolts
  • 1" stainless steel sleeved bore
  • Unpolished aluminum
  • Deep piston design for manual or power brakes
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Key Specs

MFG. Part #91031428
BrandSpeedway Motors
Master Cylinder Bore Size1 Inch
Master Cylinder MaterialAluminum
FinishNatural
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Need To Know

Quick and Easy Returns

Return Policy

Speedway Motors 91031428 Details

As featured on Classic Truck’s Week to Wicked. Watch the transformation here!

Brake fluid can ruin your master cylinder in just a few years. Stop the problem by using a stainless steel sleeved master cylinder. Our sleeved GM-style aluminum master cylinder provides a weight savings and longer service life. It has 2 mounting holes on a 3-1/4" center for 3/8" or 10mm bolts.

  • 1" stainless steel sleeved bore
  • Unpolished aluminum
  • Height from center line to the top most point on the retaining bar is 3.5"
  • 3/8"-24 inverted flare ports on each side
  • 'Standard' or 'Long' thread 3/8"-24 IF male fittings should be used
  • 'Short' thread IF male fittings will not seal properly
  • Includes plugs for the side not used
  • Deep piston design for manual or power brakes 
  • Pushrod NOT included

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

Speedway Motors 91031428 Specifications

KEY SPECS
MFG. Part #91031428
BrandSpeedway Motors
Master Cylinder Bore Size1 Inch
Master Cylinder MaterialAluminum
FinishNatural
GENERAL
PositionFirewall
Brake System TypeDisc/Drum
Outlet CountTandem
Reservoir TypeIntegral
Reservoir IncludedYes
Outlet Fitting3/8"-24 IFF
Overall Width4.3"
Overall Height4.75"
Mounted Length8"
Centerline of Holes3.25"
Sleeve MaterialStainless Steel
Sold in QuantityEach
NotesHas a deep well piston that can be used with a manual pedal. Includes an adapter to fill the deep well so it can be used with a booster.9103186 3/8-24 brass inverted flare male plugs for ports. Or 9103190 steel plugs.

Ratings & Reviews

4.4

39 Reviews

Overall Assessment

Customers appreciate the product's high-quality build and performance, noting its suitability for various car models. The lightweight design of the aluminum master cylinder appeals to many users, and it offers longevity due to its rust-resistant nature. The stainless sleeve was also mentioned as a beneficial feature to prevent potential corrosion. Some customers shared that they achieved a significant improvement in pedal feel and braking system performance after the product installation. However, there were reported issues about leaking and the need for deeper-threaded fittings. Despite this, many customers would purchase again because of its positive impact on their systems.

4.4

39 reviews

5

27

4

7

3

0

2

2

1

3

Most Liked Positive Review

4.0

i'm not sure how to rate a master cyl

your master cyl. seems to be working good light weight operating well

Most Liked Negative Review

1.0

Bad master cylinder

Installed this master cylinder on a completely new system 4-wheel discs bench bleed the master as you should. Could not get the brakes to function properly after bleeding spongy breaks went to the floor. Worked on it for three days installing residual valves and swapping the reservoir's from front to back. Called speedway no help what so ever when asking questions about the functions of the master cylinder. If it had residual vales built in and what reservoir went to the front and which one went to the back they avoided giving me a direct answer i also referred to the Q&A questions and they were contradicting with he told me which is Telling me they don't even know anything about the product they stock. Long story but master cylinder is bad out of the box bought a good master cylinder from someone else works great. Really expected more from speedway.

Filter by Ratings

Yes

4.0

a year ago

Joe

Santa Clarita

Verified

Yes, I use it on my 49 Chevy Pickup to replace my old worn out master cylinder.

Great upgrade for a classic master cylinder

5.0

a year ago

Kurt

Pittsburgh PA

Verified

I love the weight savings of the aluminum and the longevity of the stainless-steel sleeve.

Would Recommend

Nice piece

5.0

3 years ago

Scruffy

Milwaukee, WI

Verified

Used this as a replacement on my 41 Chevy. Used Dot 5 and zero issues bleeding the system and a nice pedal

Would Recommend

Yes, very good product

5.0

3 years ago

Foose

01027

Verified

I used this on my 33 Dodge build, I like the look of it.

Would Recommend

Nice piece, but...

4.0

3 years ago

Scruffy

Milwaukee.

The Master Cylinder itself is a nice piece. Two points on contention though. 1) the bench bleed kit is pretty much a joke, not really made for this master. 2) I wish the front side of the mounting flange was machined parallel to the back side machined surface. The one I received is as cast at about 10-15 degrees from parallel to the back side. Couple minutes in the Bridgeport took care of that and I'm sure voided any kind of warranty...Also don't be afraid to use Dot 5, mine works just dandy using it.

Would Recommend

Lightweight yet stock configuration Master Cylinder

5.0

3 years ago

70' SS

Tennessee

Verified

Fits the bill for the diet my clandestine 70' SS is on to promote stock appearance yet street sleeper/pro stock performance

Would Recommend

good product

5.0

4 years ago

couper

las vegas

Verified

worked great

Would Recommend

Perfect balance

5.0

5 years ago

Big daddy

Wentzville mo

Verified

Replaced a 94-95 cobra master cylinder with this Corvette style and a pv4 proportion valve and the feel is night and day difference. Should of done this years ago.

Would Recommend

I will recommend Speedway to people

5.0

5 years ago

James Jacob

Pittsburg Texas

Verified

Good part along with the rest of the parts of My order that allowed Me to upgrade the braking system for my baby bird

Would Recommend

Good Choice

5.0

5 years ago

Joe

Windsor ca

Installed on my 62 C10 with disc drum brakes.....works well, good pedal feel

Would Recommend

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Showing 10 of 39 reviews

Questions & Answers

28 Questions • 21 Answers

Maybe a stupid question but could you use this in a drum/drum setup? Thanks

by Daniel

• 7 years ago

1 answer

I am using your vette style master cyl in a disc/ disc hot rod . Does it matter which resevoir is plumbed to the front brakes?

by JON

• 7 years ago

1 answer

Can this master cylinder be used with disc/disc brakes?

by Bill

• 7 years ago

5 answers

I have a 72 K10 that I have put a Dana 60 with Disk Brakes under and the front axle is a Dana 44 with Drum Brakes. I need a Proportioning Valves so I can get different Braking from the rear axle depending on the load that I have on the truck. I have two questions ; First is there a special Master Brake Cylinder that I should use, and second, what Proportioning Valve should I use

by Dave

• 8 years ago

4 answers

Hello, will this mount to my 1969 C 10 with front disc, rear drums? Thank

by David

• 8 years ago

5 answers

Will this work on a 76 Nova with manual brakes? Front Disk rear drum.

by Kenneth

• 9 years ago

1 answer

Wondering if this will work on my 1939 chevy coupe. Just added rear disc so I need a master that will work for my 4 disc brake setup.

by Eddie

• 9 years ago

1 answer

What is the stoke of this master cylinder?

by Kam

• 9 years ago

1 answer

Will this fit and work on my stainless 8" booster dual diagphram ? Also, will it be sufficient for a disc/disc setup?

by CherryBrah

• 9 years ago

1 answer

Sirs, how much of a weight difference is there from a similar GM iron unit? Thank you

by Steve

• 9 years ago

1 answer

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