What front brake hoses on a 72 to 73 disk brake conversion

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T-Man700

T-Man700

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I know some have had this conversation before but here goes. I wanted to keep my front stabilizer from my 72 so I swapped the spinals and calibers to the rear. The factory 73 hoses will not work, so I bought a set for a 69 Camaro disk car because someone told me that should work. Well, I'm back to square one. That doesn't work either, unless I ordered the wrong one. They're has to be a crap load of people who have done this. So what do I buy that fits, thanks.
 
T-Man700 said:
I know some have had this conversation before but here goes. I wanted to keep my front stabilizer from my 72 so I swapped the spinals and calibers to the rear. The factory 73 hoses will not work, so I bought a set for a 69 Camaro disk car because someone told me that should work. Well, I'm back to square one. That doesn't work either, unless I ordered the wrong one. They're has to be a crap load of people who have done this. So what do I buy that fits, thanks.
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Found some earlier posts, no need to beat a horse, thanks.
 
I have used both '69 Camaro disc brake hoses and F/M/J (Aspen, Volare, Diplomat, etc.) hoses for rear-hung caliper installations. No problems.
Why did your Camaro hoses not work? Too short? Wrong fittings? Are you sure they sent you the right ones?
 
70 C body... double check me, when I say double-check me I mean make sure the banjo fitting and the threaded end is the same I'm pretty damn sure they are I'm positive I did that in my FMJ swap to sway barred 66 sat... basterds hung em upside down... drove me nuts...
 
Out of couriosity, why wouldn't 72 73 A body hoses fit, assuming the calipers are mounted in the stock orientation?
 
I just did this very conversion on my 69’ bee. I used calipers and hoses for a 1980 volare with rear mount calipers and they worked like a charm. The problem with using calipers intended to be front hung is those cars had the hard brake lines in the front of the upper A arm on the frame so you run into bad hose routing. The cars intended to have rear mount calipers like the late model volare had the hard brake line behind the Upper A arm like drum brake cars have. If you look at the two said calipers you will see that the front hung caliper has the bleeder and hose connection on the top and the rear mount calipers have the bleeder on top and hose connection on the bottom.
 
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Dana67Dart said:
Out of couriosity, why wouldn't 72 73 A body hoses fit, assuming the calipers are mounted in the stock orientation?
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No he swapped the calipers to the rear as many of us do for anti sway bar clearance. The volare ones are "plenty long" What I used I used to know how to find a pic, no more....................

Make CERTAIN you get the bleeders UP (swap calipers side to side)
 
My car was completely apart when when I converted one of my A-bodies to disc brakes. Knowing that the sway bar caliper issue would be a problem I modified the K-member as this was an original big block car. I removed the bottom half of the K-member and replaced it with one from a 73 and up and used the later model control arms, spindles and brake components all located in the stock location.
 
We’ll, Hate to admit it but I bought the rear hoses instead of the front ones about a year ago. Oh well, they didn’t cost too much. Guess I was buying something else from Rockauto and f…ed up. Thanks to all.
 
Jeez, just get a swaybar for '73 and later, use all factory parts, assemble like the factory did, and be done with it.
 
jos51700 said:
Jeez, just get a swaybar for '73 and later, use all factory parts, assemble like the factory did, and be done with it.
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There are factory parts available that work with the early sway bar with no issues.
 
cudascott said:
There are factory parts available that work with the early sway bar with no issues.
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Good point, I'll clarify.

Get all factory parts from a '73-'76 A-body, assemble it like the factory did, and be done with it.

It's not like there's some huge advantage to running the earlier sway bar, and five or ten years from now you're going to have to try to remember what parts you used if you do this mish mash stuff.
 
69 Camaro with a 396 and disk brakes. It's dead nuts perfect. This is the same setup your talking about. Yes this is mine.

20170704_220653.jpg
 
jos51700 said:
Good point, I'll clarify.

Get all factory parts from a '73-'76 A-body, assemble it like the factory did, and be done with it.

It's not like there's some huge advantage to running the earlier sway bar, and five or ten years from now you're going to have to try to remember what parts you used if you do this mish mash stuff.
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Yeah, just swap the entire K frame, replace the LCA's because the 67-72 sway bar tabs are in the wrong spot for the 73+ bar and buy a new sway bar instead of just buying longer hoses for the brake kit you already have. That makes sense.
 
72bluNblu said:
Yeah, just swap the entire K frame, replace the LCA's because the 67-72 sway bar tabs are in the wrong spot for the 73+ bar and buy a new sway bar instead of just buying longer hoses for the brake kit you already have. That makes sense.
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I don't think it was stated, but it seems everyone is assuming the use of slider-style calipers. Do you know which hoses to get if you want to do the Mopar 73+ A-body disc conversion on a 72-earlier A-body if wanting to use rear-mount pin style calipers and 11.76 rotors?
 
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jos51700 said:
Good point, I'll clarify.

Get all factory parts from a '73-'76 A-body, assemble it like the factory did, and be done with it.

It's not like there's some huge advantage to running the earlier sway bar, and five or ten years from now you're going to have to try to remember what parts you used if you do this mish mash stuff.
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You know my 66 satellite had a 73 340 but with the steel crank, a van transmission from the late '80s early 90s with the low gear set, I've had the rear end Center chunk part and so many cars and trucks now I've lost track of where it came from and the brakes come to find out where an FMJ conversion, but because K was changed to 70 and up, the PO had rear mounted the calipers but with the bleeders the wrong way..... all I can say is good luck getting the nuts out of the inside of the frame rails that I put on there for that adjustable proportioning valve... it was a hat trick and a half just to put them in! And I probably did it with the mill out, there was more Frankenstein stuff as well I made my own bracket for the four shifter because the van transmission didn't come with the factory mounts for the pivot shaft piece with the two bolts I'll see if I can find it and post it up in another thread
 
1972Duster340 said:
I don't think it was stated, but it seems everyone is assuming the use of slider-style calipers. Do you know which hoses to get if you want to do the Mopar 73+ A-body disc conversion on a 72-earlier A-body if wanting to use rear-mount pin style calipers and 11.76 rotors?
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If you were going to use stock hoses I would use the 73+ challenger hoses. Those calipers would have been front mounted so they should be more than long enough for a rear mount even with the larger rotors. Your other option would be to go aftermarket and get hoses from DoctorDiff, he sells stainless braided lines for that application.
 
72bluNblu said:
If you were going to use stock hoses I would use the 73+ challenger hoses. Those calipers would have been front mounted so they should be more than long enough for a rear mount even with the larger rotors. Your other option would be to go aftermarket and get hoses from DoctorDiff, he sells stainless braided lines for that application.
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Thanks for the reply. It looks like Dr. Diff's stuff is not for pin-style calipers. Other research agrees with your suggestion of the 73+ Challenger hoses (1970-74 E-body/1970-72 B-body hoses) for the 1970-72 B-body/1970-74 E-body pin calipers (as opposed to 1973-78 B-body calipers, requiring the block-ended hose fittings).

My concern is that (for 1972-earlier A-bodies with front anti-sway bars), several respected sources say to avoid rear-mounting the calipers out of concern for flex-line/brake hose routing. I do realize there are multiple kits on the market that do rear-mount the calipers, and I'm not sure what accommodations have been made for safely routing the flexline/brake hose. Notably, all of these kits use slider-style calipers. So, no matter what the solution is to rear-mount sliders on a 1972-earlier A-body with reverse-mounted 1973-76 A-body knuckles, it appears this solution is only for sliders.

I did ask Cass, from Doctordiff.com about this, and he replied custom stainless steel flex lines would be required, but routing would still be questionable. I realize Cass is an expert. I just thought I'd pose the question on here in case someone has different information.

Richard Ehrenberg suggests a solution by simply moving the hardline frame mount from rear of wheel to front of wheel and then running the aforementioned 1970-74 E-body/1970-72 B-body cables.

So it appears, if you want pin calipers, you can't safely "just" rear-mount the calipers and use factory (or even custom) flex-lines. You have to either move the hardline mounting point or else swap in a 1973-76 K-frame, LCAs, upper control arm ball joint (either by using an adapter for the 1972-earlier UCA or else by using a 1973-76 UCA) and anti-sway bar.

I don't think this is new information; it's just clarification and a renewed search to see if there has been any other solution. It seems most people use the sliders, so most discussion is about the sliders. But for the sake of accuracy, the pin-calipers also need to be part of the discussion. It's possible to use them, but requires more changes.

Maybe this point will help the next guy contemplating a disc brake conversion decide what's best for him and his car.
 
1972Duster340 said:
Thanks for the reply. It looks like Dr. Diff's stuff is not for pin-style calipers. Other research agrees with your suggestion of the 73+ Challenger hoses (1970-74 E-body/1970-72 B-body hoses) for the 1970-72 B-body/1970-74 E-body pin calipers (as opposed to 1973-78 B-body calipers, requiring the block-ended hose fittings).

My concern is that (for 1972-earlier A-bodies with front anti-sway bars), several respected sources say to avoid rear-mounting the calipers out of concern for flex-line/brake hose routing. I do realize there are multiple kits on the market that do rear-mount the calipers, and I'm not sure what accommodations have been made for safely routing the flexline/brake hose. Notably, all of these kits use slider-style calipers. So, no matter what the solution is to rear-mount sliders on a 1972-earlier A-body with reverse-mounted 1973-76 A-body knuckles, it appears this solution is only for sliders.

I did ask Cass, from Doctordiff.com about this, and he replied custom stainless steel flex lines would be required, but routing would still be questionable. I realize Cass is an expert. I just thought I'd pose the question on here in case someone has different information.

Richard Ehrenberg suggests a solution by simply moving the hardline frame mount from rear of wheel to front of wheel and then running the aforementioned 1970-74 E-body/1970-72 B-body cables.

So it appears, if you want pin calipers, you can't safely "just" rear-mount the calipers and use factory (or even custom) flex-lines. You have to either move the hardline mounting point or else swap in a 1973-76 K-frame, LCAs, upper control arm ball joint (either by using an adapter for the 1972-earlier UCA or else by using a 1973-76 UCA) and anti-sway bar.

I don't think this is new information; it's just clarification and a renewed search to see if there has been any other solution. It seems most people use the sliders, so most discussion is about the sliders. But for the sake of accuracy, the pin-calipers also need to be part of the discussion. It's possible to use them, but requires more changes.

Maybe this point will help the next guy contemplating a disc brake conversion decide what's best for him and his car.
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I think you're getting too far into your head on this and listening to entirely too much noise on the internet. The routing differences between the pin and slider style calipers are not that different. I have heard arguments against both the front and the rear mount calipers, depending on which hose route that particular person thinks is factory. But both front and rear mounted calipers were used by the factory, and the hard line take off location did not change. The primary issue is the length of the hose, and in your case that shouldn't be an issue. The other issue that comes up is direct interference, like with some of the B-body calipers that have the bottom mounted hose which literally hits hard parts on an A-body application. That shouldn't be the case with E-body pin type calipers.

Here's the deal, I've run front mounted pin style calipers on my '72 Challenger with 11.75" rotors. The Challenger has its hard line location/hose take off to the rear as well, so it runs its hose line from behind the UCA to the forward caliper. My '74 Duster came with factory disk brakes, it has a rear mounted hard line, and the 73+ calipers were front mounted. And I've run the calipers to the rear too, the 13" Cobra kit from DoctorDiff that's on my Duster now has the calipers to the rear and uses the factory hard line mount too. Hasn't been an issue, and I've run them that way for tens of thousands of miles. I don't know why the pin style calipers being rear mounted would be such an issue. Yes, I get that the hose location on the caliper is a little different, but it's not insurmountable.

I would just buy a set of '73 Challenger hoses and see if it works, since those should be the cheaper option. It's not hard to check the routing, just cycle the steering lock to lock and the suspension up and down. There's really no "routing" to do with the calipers to the rear, it's really just making sure the hoses are long enough to allow the full travel of the suspension and steering. If there's an issue you should be able to address it with a custom hose, which isn't that big of a deal. The Challenger hoses thread right into the caliper, if that doesn't work then a banjo end with a bolt should solve the problem.
 
I used the 69 Camaro lines.
Another FABO member suggested 73 Roadrunner lines, I think I may change.
 
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