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This is a complete bolt in kit that uses a modern power booster and dual circuit master cylinder (and proportioning valve) mounted to the firewall using the bolt holes for the factory air box. It shares almost nothing in common with the original 1957 and 1958 buick brake system. a new brake pedal is included that pivots from an entirely different location. This does away with the complicated pedal bracket mechanism and gives you a modern 6:1 pedal ratio. The brake pedal bracket and pushrod now go through the factory air vent opening, not the factory location. The brake pedal uses a GM brake pedal pad and has an original appearance and location. A modern GM booster and master cylinder give a significantly improved braking feel and power while adding safety through the dual circuit system. The new firewall bracket bolts to and supports your steering column same as factory. 
This can be used with factory drums, disc/ drum or disc/ disc. Let me know what brakes you have at check out and I will send the correct proportioning valve. 
It will have the pedal feel of a modern car- minimal effort required with a positive and firm feel. No more soft or sloppy pedal! 
Installation is fairly straightforward- no cutting required, this kit doesn't involve anything permanent that can't be undone in a couple hours! You have to remove the driver side air box, vent door, master cylinder, a small section of brake lines, and then this kit bolts in. Brake lines are included and pre-bent. Installation time is about 4 hours. 
Brake Lines: Two brake lines are included. One goes from rear proportioning valve to feed the rear brakes (you will have to splice in to your original rear brake feed).  The other brake line goes from the front of the new proportioning valve to the factory T junction block located near the front driver side wheel and feeds the front brakes (no cutting or flaring needed). 
This is only for 1957 and 1958 Buicks. It fits all models of Buicks for those years but does not fit any other years.
This kit comes with everything including proportioning valve, brake lines, and hardware! All you need is brake fluid and a port on your intake to plug into vacuum. 
Also, you will have more room in the valve cover area that the original air box. so it clears all original engines just fine, and will provide additional clearance for vehicles with a swapped engine. 
The firewall box has water drain spouts and new drain hose is included. water will be able to drain out from the windshield area at this two points. 
What you get: 
  • Firewall box made that is an exact fit for 1957-1958 Buick firewalls
  • Brake pedal bracket, goes through air vent opening 
  • Brake pedal W/ Bushings, clevis pin, and rubber pad 
  • GM style brake booster
  • GM style master cylinder 
  • All new high quality bolts 
  • 2X 3/16" brake lines- custom cut, bent, and flared
  • Proportioning Valve + metal lines (mounts beneath MC, as pictured)  
  • 3/8 Vacuum hose
  • Water drain hose, same function as factory 
  • Misc. hardware 
  • Instructions with pictures
Chrome Parts are available. Brake Booster and Master Cylinder in chrome is +60. The chrome master cylinder is made out of aluminum instead of cast iron.
All metal parts are CAD designed, laser cut, formed with a compuer conrolled press brake, tig welded, and powdercoaed satin black right here in the Pacific Northwest.

1957-1958 Buick Power Brake Conversion Modern Booster and Master Cylinder G13

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