Disc Brakes question

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I am converting to Disc Brakes for 1972 Dodge Dart , it has 9 inch Brake drums and the Disc Brakes supplier tells me i have to install 10 inch Spindles, my question is , do i have to replace the Upper Control Arms and Lower Ball joints when i install the 10 inch spindles ???
 
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Are you using an adapter plate for the brake set up as opposed to factory 73+ Disc parts? If you are, and he wants you to use 10” drum spindles, all the ball joints should work. Changed to big in 73
 
I am converting to Disc Brakes for 1972 Dodge Dart , it has 9 inch Brake drums and the Disc Brakes supplier tells me i have to install 10 inch Spindles, my question is , do i have to replace the Upper Control Arms and Lower Ball joints when i install the 10 inch spindles ???
Let's start with "what are you using" for the conversion. You going with factory 73/ later discs, or is this some conversion aftermarket like Thunderbird or whatever?
 
Let's start with "what are you using" for the conversion. You going with factory 73/ later discs, or is this some conversion aftermarket like Thunderbird or whatever?
Installing SSBC kit, and states must have 10 inch Drum Spindles, i have 9 inch drums
 
The reason that I mentioned downloading the parts manual is that it has the part numbers for the different set ups. It would be easy to look up the part numbers and see if they fit more than 1 application.
Advice... skip adapter setups and go with the later factory parts. Never a problem getting everyday parts and it is factory.
 
The reason that I mentioned downloading the parts manual is that it has the part numbers for the different set ups. It would be easy to look up the part numbers and see if they fit more than 1 application.
Advice... skip adapter setups and go with the later factory parts. Never a problem getting everyday parts and it is factory.
ok, thanks i will look at the information and see what i can figure out,
 
I am converting to Disc Brakes for 1972 Dodge Dart , it has 9 inch Brake drums and the Disc Brakes supplier tells me i have to install 10 inch Spindles, my question is , do i have to replace the Upper Control Arms and Lower Ball joints when i install the 10 inch spindles ???

Installing SSBC kit, and states must have 10 inch Drum Spindles, i have 9 inch drums

It depends, because there are two different spindles for the 10” drums. ‘68-72 the 10” drum spindles used the same small upper ball joints as the 9” drum spindles. But in ‘73 the 10” drum spindles started using the same large upper ball joints as the 73+ disk brakes.

So, it depends on which spindles that kit is designed to use. What’s the part number of the kit?
 
This from the link I posted above.
Now for those owners of cars not covered above, here are some tips for braking upgrades and swaps:

'62-'72 A-BODIES (Dart, Duster, etc.)
If your car now has 9-inch drums, the first step up would be the 10" drums used on all '65-up 8-cyl cars. We frankly wouldn't drive an A-body over 40 mph with the 9-inch drums, for reasons having nothing to do with the brakes. The small ball-joint-to- knuckle bolts, which are loaded in shear, are known to snap, usually at the most inopportune time.

The 10-inch, ‘65-72 drums are a simple R&R bolt-on. You'll need a set of the 10" drum ball joints and the aforementioned larger bolts, of course. The next step up, incrementally, would be to use the factory 4-piston Kelsey-Hayes setup. This has the advantage (or disadvantage, depending on your point of view) of keeping the weird 4-inch bolt circle hubs. If you go this route, you'll still need to swap master cylinders and add a proportioning valve as we outlined in the main text. But these brakes aren’t cheap or common anymore, and are prone to piston siezing if left unattended for any length of time.

The ultimate swap would be the unicast rotors (either size) as outlined above. To do this, you'd need everything in our parts list plus a pair of upper control arms and all four ball joints from a '73-'76 disc-brake A-car. For factory sway-bar cars, the same caveats apply to the A-bodies as we outlined in the main text for the late-sixties B-cars. But then you’ll have brakes up the yazoo. Incidentally, this is what stops the famous Mopar Action “Green Brick”.

'73-'76 A-BODIES
These cars came in two flavors, drum and disc, with the drum cars being similar to the '72-down cars (see above), with the main difference being the use of the larger ‘73-up B/E-body inner wheel bearing. The disc-equipped cars already have unicast rotors, but they used slider-type calipers. The cheapo upgrade is just swap to semi-metallic pads (slider type) and be happy. You can also use the 11.75- inch rotors and yet keep your slider setup by simply using caliper adapters from a '76-up slider- equipped B-body (these were typical on the 2-door versions such as Cordobas). You can also go all the way to the less-likely-to- stick pin-type calipers. For this, just use the adapters on our parts list, along with pin calipers from a '73-up B-body. This is handy because the '73-up calipers use the same hollow banjo-bolt hose attachment method as the original slider calipers, and you'll be able to retain your original hoses.
 
This from the link I posted above.
Now for those owners of cars not covered above, here are some tips for braking upgrades and swaps:

'62-'72 A-BODIES (Dart, Duster, etc.)
If your car now has 9-inch drums, the first step up would be the 10" drums used on all '65-up 8-cyl cars. We frankly wouldn't drive an A-body over 40 mph with the 9-inch drums, for reasons having nothing to do with the brakes. The small ball-joint-to- knuckle bolts, which are loaded in shear, are known to snap, usually at the most inopportune time.

The 10-inch, ‘65-72 drums are a simple R&R bolt-on. You'll need a set of the 10" drum ball joints and the aforementioned larger bolts, of course. The next step up, incrementally, would be to use the factory 4-piston Kelsey-Hayes setup. This has the advantage (or disadvantage, depending on your point of view) of keeping the weird 4-inch bolt circle hubs. If you go this route, you'll still need to swap master cylinders and add a proportioning valve as we outlined in the main text. But these brakes aren’t cheap or common anymore, and are prone to piston siezing if left unattended for any length of time.

The ultimate swap would be the unicast rotors (either size) as outlined above. To do this, you'd need everything in our parts list plus a pair of upper control arms and all four ball joints from a '73-'76 disc-brake A-car. For factory sway-bar cars, the same caveats apply to the A-bodies as we outlined in the main text for the late-sixties B-cars. But then you’ll have brakes up the yazoo. Incidentally, this is what stops the famous Mopar Action “Green Brick”.

'73-'76 A-BODIES
These cars came in two flavors, drum and disc, with the drum cars being similar to the '72-down cars (see above), with the main difference being the use of the larger ‘73-up B/E-body inner wheel bearing. The disc-equipped cars already have unicast rotors, but they used slider-type calipers. The cheapo upgrade is just swap to semi-metallic pads (slider type) and be happy. You can also use the 11.75- inch rotors and yet keep your slider setup by simply using caliper adapters from a '76-up slider- equipped B-body (these were typical on the 2-door versions such as Cordobas). You can also go all the way to the less-likely-to- stick pin-type calipers. For this, just use the adapters on our parts list, along with pin calipers from a '73-up B-body. This is handy because the '73-up calipers use the same hollow banjo-bolt hose attachment method as the original slider calipers, and you'll be able to retain your original hoses.

And? The 73+ 10” drums use the larger ball joint as well as the larger wheel bearing.

And SSBC conversion the OP asked about isn’t in that article. Rather than making the OP sort through a bunch of information he doesn’t need, why not get to the point?

Ultimately what he needs to know is which set of 10” drum spindles he needs for the kit he bought. And that has more to do with the SSBC kit and what spindle it needs than anything else.
 
Point is to use all factory parts. Aftermarket conversions are always a chore. Over the counter parts are always( at least to me) the best way to go. The factory knows more than anybody what the correct set-up is. Millions installed, parts everywhere if you wear out or break something. Return the kit...,
 
Point is to use all factory parts. Aftermarket conversions are always a chore. Over the counter parts are always( at least to me) the best way to go. The factory knows more than anybody what the correct set-up is. Millions installed, parts everywhere if you wear out or break something. Return the kit...,

Oh BS. There are plenty of great aftermarket kits out there, many of which will outperform a lot of the factory parts.

And again, that’s not what the OP asked. Sure, personally I wouldn’t use a conversion kit that also required a spindle swap since you can use factory disk parts if you do a spindle swap. But that wasn’t the question and the OP has a different kit. So why not actually answer the question and help?
 
It depends, because there are two different spindles for the 10” drums. ‘68-72 the 10” drum spindles used the same small upper ball joints as the 9” drum spindles. But in ‘73 the 10” drum spindles started using the same large upper ball joints as the 73+ disk brakes.

So, it depends on which spindles that kit is designed to use. What’s the part number of the kit?
thanks for your information, the kit I have is SSBC A153-1 SSBC USA Drum to Disc Brake Conversion Kits , my mechanic called SSBC and they told him that they are designed for 10 inch front brakes spindles
 
thanks for your information, the kit I have is SSBC A153-1 SSBC USA Drum to Disc Brake Conversion Kits , my mechanic called SSBC and they told him that they are designed for 10 inch front brakes spindles

Based on the application list and the advertised year range for the kit it appears you need 10" drum spindles for a 67-72 A-body. That is important because there are 2 different versions of the 10" drum spindle, either 67-72 or 73+. For your car the 67-72 spindles don't require any changes at the upper ball joint or UCA, and just an increase in the bolt diameter for the lower ball joints compared to the 9" drum spindles. The 73+ 10" drum spindles use the later larger upper ball joints, so you'd either need a UCA swap to 73+ UCA's and upper ball joints or a set of ball joint taper adaptors. They also use a different wheel bearing, so, it makes a difference for the kit, the early and late 10" drum spindles would not be interchangeable for the kit either.

So, based on what I see you shouldn't need to do anything with the upper ball joints or UCA's. You will need to either drill your lower ball joints for the larger diameter bolts or buy new ones, and source the larger bolts. And you will need to find a set of 67-72 10" drum spindles. They're not reproduced, so, you will need to find a good used set.

I would agree that the SSBC kit was probably not the best choice because you have a source a used set of spindles for it. As opposed to using a kit that's based on the 73+ disk spindles, because they're reproduced and readily available and use an improved larger wheel bearing. But those would require ball joint adaptors or new UCA's, so, there's always a trade off.
 
Based on the application list and the advertised year range for the kit it appears you need 10" drum spindles for a 67-72 A-body. That is important because there are 2 different versions of the 10" drum spindle, either 67-72 or 73+. For your car the 67-72 spindles don't require any changes at the upper ball joint or UCA, and just an increase in the bolt diameter for the lower ball joints compared to the 9" drum spindles. The 73+ 10" drum spindles use the later larger upper ball joints, so you'd either need a UCA swap to 73+ UCA's and upper ball joints or a set of ball joint taper adaptors. They also use a different wheel bearing, so, it makes a difference for the kit, the early and late 10" drum spindles would not be interchangeable for the kit either.

So, based on what I see you shouldn't need to do anything with the upper ball joints or UCA's. You will need to either drill your lower ball joints for the larger diameter bolts or buy new ones, and source the larger bolts. And you will need to find a set of 67-72 10" drum spindles. They're not reproduced, so, you will need to find a good used set.

I would agree that the SSBC kit was probably not the best choice because you have a source a used set of spindles for it. As opposed to using a kit that's based on the 73+ disk spindles, because they're reproduced and readily available and use an improved larger wheel bearing. But those would require ball joint adaptors or new UCA's, so, there's always a trade off.
Thank you for your good information, ( much appreciated ) I will proceed in getting the 10 inch spindles and i will follow up with the installation to see how it goes. nm
 
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