Disc Brake swap on 69 drum brake equipped Super Bee

[pwtjr]

Need a little insight on upgrading the front brakes on my 69 Superbee.

A buddy of mine sold me a setup off his car, a 71 Duster. The brake spindles came off of a 75 Dart. He went with new K member-rack&pinion-coil over setup and donated the whole shebang to me. Said use whatcha can ....

I know there are a multitude of posts on this very subject, and I've done my best to read most of them. All good info. That's why I know the spindles will be ideal on my car.

1st question: He supplied the lower A arms (original off his Duster), which have all new shafts and bushings and stiffener plates. I notice the sway bar attachment point is different than on my control arms. I was wondering if anyone makes a sway bar or sway bar links that will allow me to just use the control arms and mount the calipers in front like they are supposed to ? Or can I even use those lower control arms on my B Body?

2nd question: If they are not usable or no one makes a sway bar link, then I will do like most everyone else and mount the calipers in the rear. So pretty much swap sides and swap Lower Ball Joints? There is not caster built into the spindles or anything like that? I assume caster setting is all done with the Upper Control Arm bushings/settings right?

3rd question: With the calipers mounted in rear, what brake line does everyone use and who do you get it from? I've seen posts with various options and opinions on this.

4th question and final: I know I will need a different master cylinder per my car is originally a 4 drum non-power car. But can I retain the combination valve and just add an adjustable proportioning valve to the rear brakes or do I need a whole new combination valve too?

Thank you for reading. Thank you more for replying with any info. Sorry for multiple questions but they are all related and I'd like to know what I'm up against here before I tear into the greasy 46 year old front end.

Regards,
Paul :eusa_think:

 

[Deleted member 214]

Did a similar swap on my 70. I can help with half your questions...

1) Use the lower control arm and ball joint already on your car.

2) no problem in suspension geometry in this swap.

3) I forget!

4) Don't know.

 

[Trashdog67]

4. I used the original combination valve and spliced a proportioning valve into the rear brake line. No problem.

 

[pwtjr]

Sweet, I was hoping to retain that valve and do just as you said. Appreciate the info.

I'm going to assume if I go to a local Napa I can just buy a master cylinder for a 75 Dart with manual discs? There is some chatter on other posts about issues with the brake pedal rod. This is also something I guess I should have asked about....

 

[CoronetDarter]

Dr. Diff (Cass) has most if not all the components you need. I bought my disc brake conversion kit from him. Cass sells the ss brake hose, bendix style m/c, combo valve, etc. He's a great guy to deal with too. www.doctordiff.com

 

[pwtjr]

Sounds like just what the doctor ordered.

Thank you I will check out his website

 

[terzmo]

I just used the 73 spindles...same as your 75's and installed the rotors...caliphers...new brake lines..no prop valve and no new master cylinder and the car stops excellent. Third car I've done this on....oh...and a frontend alignment. Nothing new to the suspension except the spindles....Good luck and enjoy

 

[pwtjr]

Interesting. I would have thought the master cylinder would be a must. So your pedal feel is good and all? Maybe worth throwing the spindles on there and see what I get with current one.

Thanks for the info

 

[Propwash]

The master cylinder should be a must. Your non-power drum/drum master has residual valves in the master ports. You do not want a residual valve holding residual pressure on Disc's, like they do with a drum brake. They're needed in a drum application to overcome spring pressure. In a disc car they will cause brake drag, brakes heating up and eventually brakes locking up. Another difference is reservoir size/capacity. Typically in a drum/disc combo M/C, the disc side of the master has a much larger reservoir vs. the drum, for the extra volume needed on the disc side. B-Bodies of your year/model did not come with manual Disc/Drum combo's, so you won't find a factory type M/C for your year/model, but plenty of folks convert to the A-Body manual Disc/drum master, just like the one you mentioned.

As far as your pedal rod goes, I couldn't tell you if that A-Body rod will work or not. Like mentioned they didn't have a factory disc/drum car in your model/year. Just remember, you need to have a certain pre-gap from the end of the rod to the back plunger/piston of the master. Too much gap and you excessive pedal play before braking. Too little play and the brakes will never fully disengage, drag, heat up and eventually lock up. A Factory Service manual should give you the proper gap. I'd say if you can't make the factory A-Body rod work, go with an aftermarket adjustable. You can find them pretty easily.

As far as your brake lines, check out the link coronetdarter provided or surf the member restoration threads here on FBBO. There is a lot of us over there that have converted to an A-Body style braking system at the wheels. Myself, I have the caliper's mounted to the rear and got my lines from "Right Stuff"

Good luck

 

[pwtjr]

Thanks for the input and taking the time to write all of that, very helpful. Everyone is so nice and willing to help on this site. Very very cool guys. Now if it would just warm up a bit here in Indiana, atleast to above zero, I may be able to get back out to the garage and turn some wrenches on my beast.
I believe the garage shall be getting a furnace of its own sometime this summer in preparation for next winter. I can only stay out there so long with that noisy stinky salamander
Once again, thank you all so much.

 

[Propwash]

Not a problem, glad to help. I hear ya on the cold! Pretty brutal.

 

[hunt2elk]

The master cylinder should be a must. Your non-power drum/drum master has residual valves in the master ports. You do not want a residual valve holding residual pressure on Disc's, like they do with a drum brake. They're needed in a drum application to overcome spring pressure. In a disc car they will cause brake drag, brakes heating up and eventually brakes locking up. Another difference is reservoir size/capacity. Typically in a drum/disc combo M/C, the disc side of the master has a much larger reservoir vs. the drum, for the extra volume needed on the disc side. B-Bodies of your year/model did not come with manual Disc/Drum combo's, so you won't find a factory type M/C for your year/model, but plenty of folks convert to the A-Body manual Disc/drum master, just like the one you mentioned.


Good luck

The master cylinder I have been using which was made possible by Wayne-The Ramman and sold through Pirate Jack/MBM, still has a residual valve on the rear reservoir only but not the front reservoir.