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![Power Brake Booster/Master Cylinder Conversion Kit Fits Select 1955-1957 GM Full Size A-Body Models [Disc/Disc]](https://www.jegs.com/images/mini_750/500/555/555-631433.jpg)
Vehicle Info NeededJEGSPART NUMBER: 555-631433
Power Brake Booster/Master Cylinder Conversion Kit Fits Select 1955-1957 GM Full Size A-Body Models [Disc/Disc]
$22999$248.39You Save$18.40
Ships on 09/17/2026
Lowest Price GuaranteeGM Car, Disc Front & Disc Rear
Power Brake Booster/Master Cyl. Conversion KitSelect 1955-1957 GM Full Size A-Body See Fitment Tab for All Applications Disc/Disc 1.125 in. Bore Master Cyl. 8 in. Dual Diaphragm Booster Brass Proportioning Valve Zinc Sold as Kit
JEGS 555-631433 Power Brake Booster/Master Cylinder Conversion Kit Features:
- Fits select 1955-1957 GM full-size A-body models
- For front brake disc/rear brake disc applications only
- 1.125 in. bore dual-bowl master cylinder for improved hydraulic performance
- 9/16 in.-18 and 1/2 in.-20 master cylinder outlets
- 8 in. vacuum dual-diaphragm brake booster
- 3/8 in.-24/9/16 in.-18 proportion valve outlets
- Steel brake booster construction provides strength and long service life
JEGS 555-631433 Power Brake Booster/Master Cylinder Conversion Kit Notes:
- The bottom mount proportioning valve has 2 3/8-24 in. ports for the front brakes and 1 9/16-18 in. port for the rear
Part TypeBrake Master Cylinder and Booster Assembly
BrandJEGS
Package Height10.5
Package Width10.5
Package Length18.25
Weight23.0 PG
Part CategoryReplacement Parts
Master Cylinder StrokeN/A
Brake Booster TypeVacuum dual diaphragm
Master Cylinder FinishNatural
Master Cylinder Bore Size1.125 in. (28.575 mm)
QuantitySold as a kit
Mounting Hardware IncludedYes
Brake Pedal Rod Extension IncludedYes
Bowl DesignDual
Brake Booster Diameter ( In.)8.00 in. (203.2 mm)
Rear Brake TypeDisc
Brake Booster MaterialSteel
Master Cylinder MaterialIron
Master Cylinder Cap IncludedYes
Front Brake TypeDisc
Reservoir MaterialIron
Part FitmentDirect Fit
Reservoir IncludedYes
Package Qty1
Package TypeEA
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Some parts are not legal for use in California or other states with similar laws / regulations
