70 GTX Disc Brake Conversion

[Dave C]

This is my first B Body and obviously there are no front springs. I have done disc brake conversions on cars with coil springs. In that case, supporting the lower control arm was required. Does any one have a step by step, preferably with photos on the correct way to do this so I do not screw things up. Thanks

 

[moparedtn]

Professor Ehrenberg wrote the "bible" on this (using all factory parts in the swap, no less)
many many moons ago called "Disc-O-Tech" :
https://www.allpar.com/history/mopar/brakes/disc-main.html

 

[coronet68mx]

Yeap, moparedtn is right, although you'll see that at least in the U.S. find an A body for your conversion is almost impossible nowadays, all of them are gone now, not here in Mexico I have two sets, but there are other source for your conversion using the existing drum spindle, some other members will be kind enough to direct you in the right direction, good luck in your search.

 

[Fran Blacker]

Finding the pin type caliper brackets for 11.75" rotors is hard and expensive . Kits are the way to go. Did the "Disc O Tech" conversion in 2001.

 

[Billccm]

Dr Diff is the best for the money here

 

[Dave C]

Great, thanks so much. One question, I see he has a jack stand under the assembly. I know that a vehicle with coil springs must be supported under the lower control arm. Does this assembly also need to be supported when the spindle is removed? Also when the lower ball joint is replaced?

 

[coronet68mx]

Great, thanks so much. One question, I see he has a jack stand under the assembly. I know that a vehicle with coil springs must be supported under the lower control arm. Does this assembly also need to be supported when the spindle is removed? Also when the lower ball joint is replaced?

Be very careful with the torsion bar, when release the pressure, there's a bolt for that.

 

[moparedtn]

Did you think these cars don't have springs at all?
Of course they do - they're called torsion bars!

Any aftermarket kit you may select to go with (including some that ARE available without
the need for replacing the existing spindles) are going to come with instructions.
Disc-O-Tech walks you right through things as well.
Do your homework.

 

[Fran Blacker]

Easy to reliever tension on torsion bars. Download a service manual at mymopar go to tools and reference . This will take there. http://www.mymopar.com/index.php?pid=31

 

[themechanic]

This is my first B Body and obviously there are no front springs. I have done disc brake conversions on cars with coil springs. In that case, supporting the lower control arm was required. Does any one have a step by step, preferably with photos on the correct way to do this so I do not screw things up. Thanks

They have power and non power brake instructions here:

https://www.getdiscbrakes.com/knowledge-base/mopar/mopar-instructions

PST is a vendor on here and offers member discounts. The brake kits differ here and there. It depends on what you have and what you want to do.

 

[coronet68mx]

Did you think these cars don't have springs at all?
Of course they do - they're called torsion bars!

Any aftermarket kit you may select to go with (including some that ARE available without
the need for replacing the existing spindles) are going to come with instructions.
Disc-O-Tech walks you right through things as well.
Do your homework.

 

[Dave C]

Thanks, appreciate it

 

[chargervert]

I usually use 73-74 B or E body spindles, with 73-74 rotors. The 73 -74 rotors cost about $50 each,,as they are unicast one piece rotors. The 70-72 rotors cost about $250 each and are a two piece assembly. Dr Diff sells a bearing race kit to fit the 73-74 rotors to the 70-72 spindles. The 73-74 spindles have a larger diameter. Then I order 70-72 B or E body pin type calipers, brake hoses, brake pads and mounting hardware. Usually I can do the conversion for around $300 total, not including the master cylinder upgrade.