disc brake conversion

[philgarvey]

The tech library has gary hamm's tutorial on the disc brake conversion on birds 58-60. Does anyone know if the original master cylinder provides enough pressure or is another master cylinder required.

[jopizz]

You need another master cylinder designed for disc brakes or you can have the old one modified for disc brakes. Dewey's Booster Service is one place that will modify the original one.

John

[philgarvey]

thank you. I just checked out Dewey's. $145 for the modification. As a plan B, do you know if there is a compatible (make model) galaxie? lincoln? year? master cylinder or is mounting on the fire wall a problem?

[DKheld]

Booster Dewey can modify the original bendix under the hood booster to accept a modern style master cyl. The booster provides acceptable boost but not like the small dual action boosters available today.

Dewy rebuilds the boosters as well - the one he did for me has been working great for 10+ years. Believe I used a Granada or Mustang brake master cyl. As you can see the lines exit on the engine side - tight but workable.

You will also need a proportioning or combination valve and split the old single line system into a dual system.
You can't just throw a disc/drum master cyl on there and call it done. The front brakes will be different thus splitting the system and the valve (I used a combo valve). You will also need to plan to move the brake light switch to the rear drum system and extend the wiring.

I converted mine using Granada spindles 10+ years ago but I would recommend the scarebird brackets now available due to alignment issues on the Granada spindles.


Eric

edit - just saw the additional question...

I tried the Galaxie bracket once but it did not fit. May have worked with some mods to the bracket where it bolts to the firewall but then still had the brake pedal rod to deal with. That's when I went with the modified original.
It is possible to cut the old booster off and re-use the brackets for a new booster.
Search the forum on disc brakes - lots of info. Couple of different routes folks have gone. Think if you join the forum by becoming a paid member there is a complete parts list available. Makes it easy.

[simplyconnected]

Let's back up a bit... You have a '59. Does your car have a booster under the hood? If so, you can re-use your firewall bracket and all hardware back to the pedal remains untouched.

If you have a Treadle-Vac system with the booster next to the brake pedal, this job will become a bit more complicated.

In any case, as Eric said, the original booster was fine for drum brakes but it is sadly underpowered for disk brakes. As a bare minimum we use a two-stage 8" booster, that delivers more than 800 psi., from a 1" bore dual master cylinder. If a larger booster would fit, we would use it, but the two-stage 8" does the trick.

The firewall bracket raises the booster 5" and it extends it out from the firewall another 5". This is necessary to clear the shift arms on the steering column. - Dave

[philgarvey]

Thank you all. I have some work to do but that is what the off season is for. Happy new year to all.
respectfully,
phil garvey