A Body Disc Brake Swap 101

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So you bought the a arms etc from Orielly's? It's not always free shipping, but if I order it in store, its much cheaper shipping for certain. In this case, I would be asking for help in a parts list.
Sorry but I never saw your question, no I did not buy anything from oreilley's but brake hardware set and some washers for my brake lines that I didn't need, my 73-76 used and rusty upper control arms came from a guy in Tacoma, WA for $80.00 and my sister brought them to me I bought all my parts from different places, shopped and found the best price mostly on Ebay
 
Anybody have any clearence issues with a 205/70r/15?

I put a hole in the oil pan yesterday on the dart leaving the driveway- the 13s are only 22in tall, and the car is just way too low. I ordered 15" torque thrusts BBP 15x7s. The 70rs are 26.3 but 75rs are 27.1, and both are 8.1 in diameter. I have to order these online, so any words will help here! I want to go with the 27.1 tall if can? I know fine on back, concerned about up front. I hit up brown salvage for an entire used 73-76 Bbp disc brake set up, I want to use that the most, even more than Dr Diff, so it's all stock parts in the future, no need to ever figure out where/what to get if I have to replace something in 5-10 years.
 
Trying to find a couple grease boots for a 67 - 72 spindle. Have all the parts for the drum to disc brake change over, but can't find the MOOG grease boots, without spending almost $60.00 for new ball joints, each. OUCH!!!!! Any ideas?
 
Thanks for your input, S cuder. I have ordered a set of tie rod boots with same pin (.59) and Base (1.61) from that app., but they are not upper control arm boots. They will be arriving next week. Hope they will be better than nothing. Just want to keep the dirt out of the bushings and the grease off the rotors.

I bought some upper ball joint boots on ebay whose seal measures 1.75" inner diameter. They fit the 1973 and later ball joints perfectly. This is on the left. It will fit over the earlier ball joint, but doesn't seal snugly around the rim. The boot on the right is from an old stock 1972 and earlier Moog K704 and measures 1.6". Maybe use a Prothane from the list under the replacement rubber eBay piece?

New Replacement Rubber Ball Joint Boot for Moog K6145T Style Ball Joints | eBay
IMG_20220602_132835804~2.jpg



Another possible solution is to order low price ball joints from Rock Auto. The SKP SK704 sells for $4.86, and the boots look pretty decent. Better than the Prothane ones do anyway, because they have the rim around the bottom to help seal. It seems wasteful, but it could be the best option. The one thing I'd want to know is if they guarantee the picture matches the product. If not, you'd be taking a chance.
 
Im no smart man here, but I just removed all this from a 73 car, and I have new 73+ ball joints will they thread into the 71 UCA? I know the joint is bigger on the 73+ I'm just curious of they will screw into the 71 uppers or should I have removed the 73 uppers?
I read through and it sounds like I have to use the 73 UCA but I guess I'm just verifying I understood correctly.
 
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Im no smart man here, but I just removed all this from a 73 car, and I have new 73+ ball joints will they thread into the 71 UCA? I know the joint is bigger on the 73+ I'm just curious of they will screw into the 71 uppers or should I have removed the 73 uppers?
I read through and it sounds like I have to use the 73 UCA but I guess I'm just verifying I understood correctly.

You need the ‘73+ uppers. The upper ball joint not only has a larger taper on the 73+ cars, it has a larger outer diameter. You can’t thread a 73+ upper ball joint into a ‘71 UCA.

Your alternative option is to use tapered adaptors with the ‘67-72 small upper ball joints (and your current ‘71 UCA’s). DoctorDiff sells them if you want to go that route.
 
I thought so. I just wanted to verify i was reading correctly. Well guess I'll be pulling the parts car back apart again lol
 
I thought so. I just wanted to verify i was reading correctly. Well guess I'll be pulling the parts car back apart again lol
Yeah if you still have access to it that’s probably easiest. Also makes it easier to source parts in the future, you just look up a ‘73+ car for everything rather than having to get half ‘73+ parts, half ‘71 parts etc.
 
I took the complete spindle and calipers, left the lowers and uppers but I have new lower balljoints so I figured those can stay I'll just bolt the new 73 balljoint to the LCA but I'll take the 73 uppers off tonight and swap them rather than have to buy them later down the road when I assemble front end in the 71
 
Hi Bruce , This was an outstanding article. I did 2 of these swaps , but it was almost 30 years ago now. On my 71 Dart , I used the SBP set-up , and on my 69 Barracuda I used the 73-76 BBP set-up like you're doing here. I would just say the donor cars were a lot easier to find in junkyards back then. I even wrote an article about doing this conversion , and used some photos , and hand-drawn illustrations. This was for my Mopar club's newsletter. Anyway kudos to you for a clear , concise practical and well-written article. Here I find myself now 30 years later in the exact same situation I was back then. I have 2 cars I'm working on, a 70 Valiant and a 68 Barracuda , and 2 disc brake set-ups ; the SBP for the Valiant and the BBP for the Barracuda. Since the Valiant is a 4 door slant six commuter car , and the Barracuda is a 318 , which I plan to replace with a 360/408 stroker engine , that's why I'm doing it in this manner. The problem for me now is that I can't find my original article , or my notes , and one important detail escapes me. This is specifically related to the SBP set up. The new rotors are bare rotors , and have to be mated to the hubs using new wheel studs. I can't remember if I separated the 9" front drums from their hubs , and used those hubs with my new rotors , or if this would even work? Maybe you or someone else on this forum knows the definitive answer.
 
Hi Bruce , This was an outstanding article. I did 2 of these swaps , but it was almost 30 years ago now. On my 71 Dart , I used the SBP set-up , and on my 69 Barracuda I used the 73-76 BBP set-up like you're doing here. I would just say the donor cars were a lot easier to find in junkyards back then. I even wrote an article about doing this conversion , and used some photos , and hand-drawn illustrations. This was for my Mopar club's newsletter. Anyway kudos to you for a clear , concise practical and well-written article. Here I find myself now 30 years later in the exact same situation I was back then. I have 2 cars I'm working on, a 70 Valiant and a 68 Barracuda , and 2 disc brake set-ups ; the SBP for the Valiant and the BBP for the Barracuda. Since the Valiant is a 4 door slant six commuter car , and the Barracuda is a 318 , which I plan to replace with a 360/408 stroker engine , that's why I'm doing it in this manner. The problem for me now is that I can't find my original article , or my notes , and one important detail escapes me. This is specifically related to the SBP set up. The new rotors are bare rotors , and have to be mated to the hubs using new wheel studs. I can't remember if I separated the 9" front drums from their hubs , and used those hubs with my new rotors , or if this would even work? Maybe you or someone else on this forum knows the definitive answer.
Unfortunately, Bruce is no longer with us. He lost his cancer battle back in 2011. He was a wealth of information and one cool dude and a good local friend to me and online friend to a lot of people. He is sorely missed. That said, the 9" hubs will not work with disc brakes, at least I believe that was your question.
 
Unfortunately, Bruce is no longer with us. He lost his cancer battle back in 2011. He was a wealth of information and one cool dude and a good local friend to me and online friend to a lot of people. He is sorely missed. That said, the 9" hubs will not work with disc brakes, at least I believe that was your question.
Wow , I didn't realize his posts were from that long ago! Very sorry to hear about Bruce, though. My sincere condolences to his family and friends. So the missing pieces then , are the original SBP disc front hubs
 
Wow , I didn't realize his posts were from that long ago! Very sorry to hear about Bruce, though. My sincere condolences to his family and friends. So the missing pieces then , are the original SBP disc front hubs
Yeah, and they ain't easy to find. I've often wondered if it's possible to somehow make the drum hubs work, but it's probably not, or people would have been doing it.
 
Only solution is re work with mustang rotor that I can think of.
Can those be made to fit on the Mopar disc spindle? Seems it would take a lot of work to retain the small bolt pattern.
 
What a great thread !
After looking at SBP wheel options for a while now, I've decided to go to BBP. I have a 77 volare, complete I can strip the parts off of. Looks like most everything I need for info is here.
 
What a great thread !
After looking at SBP wheel options for a while now, I've decided to go to BBP. I have a 77 volare, complete I can strip the parts off of. Looks like most everything I need for info is here.
There's no arguing the multitude of wheel options compared to the SBP.
 
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