Disc brake swap

[Larry S.]

I have built a 392 hemi, and was going to put it in a 68 Coronet, but as things sometimes do, the plan has changed. I just bought a 70 Cuda and now the hemi is going in it. The thing is, as heavy as these old hemis are, I figured a swap to disc brakes on the front would be a good idea. I located the parts (A body spindles, C body rotors etc.) for the Coronet swap in a local yard. What I need to know is will the same parts work on the E body? I don't recall if the magazine article I got the parts swap info from said whether it also applied to E bodies or not, and I can't find the magazine now. I also came across a late model lightweight master cylinder in a K car, but it is on a power booster. I don't think I will be able to use a power booster due to the valve cover interference from the hemi. Will this thing work okay without the booster for my application? I know that I will have to use the aluminum adapter from MP to bolt it on, but I don't know how it will function without the booster. Thanks for the help.

[Thunderstruck]

You can't use C body rotors on A body spindles. Don't use a K car M/C it's setup for a diagonally split brake system (LF and RR hooked together, RF and LR hooked together) that your not set up for. Use an M body M/C. You may not need the MP adapter plate. When I added that M/C to my 65 Cuda all it took was a 5/16" plate to space the M/C out far enough to properly hook up with the manual brake pushrod. You might be able to bolt the M body booster up to your Coronet but don't forget that the brake pedal assembly is really different when you compare power to non-power setups. You can use a power M/C in place of a non-power M/C with the only issue being pedal feel. It'll be harder. In fact I prefer it and my wife, 5'6", 130 lbs, doesn't have any issues with it. For rotors look for 76 and up B body 11.75" rotors, easy visual- if the rotor is larger in diameter than the splash shield it's the 11.75", if the rotor is smaller it's the 10.87" rotor, same splash shield was used in either case. I can buy the big rotors for $29.99 each, Aimco brand from Autozone (look for the bigger stores that stock the rotors).

Steve

[Squad]

you can use 73-76 a-body spindles,76-78 b-body or 79 up r body police rotor mopar part no (4126545 for 15inch wheels only), Diplomat, volare police(3880685 14inch wheels), 70-72b-body 70-74 e-body calipers, caliper adapters for the 15 inch only is from a 76-78 B-body(pin type) For the 14's use the adapter from 70-74 E-body,70-75 B-body. Hoses from the 70Ebody will work. It sounds like a lot of work but it is the best combo . A rear adjustable proportioning valve may be needed.

[Larry S.]

Hey guys,
Thanks for the advice. I just got back home with my new toy, and it turns out it already has disc brakes! I will go ahead and get the other parts and use them on the Coronet, now all I need to do is figure out what I want to do with the Coronet (all out race car or street machine). Hmm....decisions, decisions.

[PRO]

A LITTLE NOTE REMEMBER E-BODIES ARE LONGER WHEELBASE B-BODIES. ALL COMPONENTS NOT AFFECTED BY WHEELBASE, NOT TRACK, INTERCHANGE. ALSO YOU HAVE GROUPS BY YEARS 1967 AND PREVIOUS, 1968-1970,1971-1974,1975-1979.HOPE THAT MAKES IT EASY TO REMMEMBER...PRO..

[Larry S.]

Thanks Pro, I kinda figured the chassis was basically the same, but I didn't know the E body had a longer wheel base. I had this 392 hemi fitted to the B body (headers, motor mounts etc.)and have been told that the engine compartment on the E body is basically the same, so everything should bolt up okay in the Barracuda.

[Christopher]

Actually the E-body has a shorter wheelbase,it's 108 for the Cuda and 110 for the Challenger.The E-body is basically a B-body with a A-body wheelbase.The B-body wheelbase is 117 or 119 depending on the style of body.Not trying to correct anyone,just in case someone new to Mopars is reading this and might get confused.

[GILBO]

when putting disc on a 68 cuda, it had 10" brakes what i need too know is if i can use the adapters etc. off a 73 to 76 dart when changing the spindles. also i'm planning to change the 11"drums on my 69 charger r/t can i use the rotors and adapters off the same 73 to 76 a body or do i need to find adapters off a diff. model

[This message has been edited by GILBO (edited December 02, 1999).]

[451boy]

Reply to the last post: Yes you can use the adapters, calipers, spindles, and rotors from the '73-'76 A body when swapping onto a B body. You should even use the A body hoses. Everything goes right on there like it was designed to (unless you have a sway bar of course!) Or you can step up to the later model 11.75 rotor and the adapters that go with them. Use the A body spindles and calipers though. These are the simple combinations. You can also fool around with reversing the spindles to gain sway bar clearance but then you have to sort out the caliper/brake line issue. I think there is a clean way to do it but I haven't built one yet that way. 80's Chrysler cars had rear mounted calipers and rear hung hoses so I think they will work but you'll have to weld a tab onto frame to hold the hose. There might be another combo which doesn't require welding but I haven't seen it yet.

[GILBO]

thanks 451boy, i was about to give up on getting an answer. the magazines were really hazy on that part or said to use a b-body adapter and rotor etc. did'nt make a lot of sense to me. knew someone had to have done this, and know for sure! thanks again.

[This message has been edited by GILBO (edited December 06, 1999).]

[451boy]

Gilbo, easy way to think about it is in terms of sets of parts. There is a big adapter and a little adapter just like there is a big rotor and a little rotor. Either combo works with the same spindle and caliper. You just have to keep the adapter and the rotor matched up in size. Actually it is hard to make a mistake since you can't physically put the big rotor on when the small adapter is there, they run into each other.

What I do when I do this swap is go to a wrecking yard and find the spindles and calipers from an A body, then go find the rotors and adapters from a B or R body. I bolt the whole thing together and buy it as a unit. The parts guys don't know I took parts from two cars and so I only have to pay for what I need.

[Larry S.]

Hey 451boy, thanks for the info. That idea of separating the parts into groups really helps simplify things! Thanks to all you other guys who posted on this topic also. This site has been a really big help, I think I've found a home here!