Identify Disc Brakes on Dart?

MoparGuy68 said
Thanks for the responses guys!

Is the "track width" different from front to rear only on A-Bodies?

I owned a 71 Challenger for over 12 years, and never noticed a difference in width from front to rear.. This Dart, I could tell when I first laid eyes on it..

After reading all the replies, it seems like I should have had some issues with wheels on my Challenger that I didn't have..

The Challenger had its factory manual drum brakes front and rear. It came from the factory with 14 x 5 steel wheels, with dog dish caps and trim rings. I had 225/70/14 tires mounted on them.

Back in 1992, I wanted to replace those wheels with 15 x 7 steel wheels. I knew absolutely nothing about small bolt pattern / large bolt pattern, or that there even was such a thing or a difference. I went to two junk yards in Southern California, where I was living at the time. The first yard had a pair of 15 x 7 wheels marked as coming off a "73 Dodge Van". The second pair of 15 x 7, that I found, at another yard, were marked "77 Chrysler Cordoba".

The 73 Dodge Van wheels would mount on my Challenger's drums both front and rear without issue. The 77 Cordoba rims would only mount on the front drums, they would not mount on the rear drums. So the Van rims were on the rear, and the Cordoba rims on the front, for the last 6 years I owned the car, with my factory dog dish caps mounted on them, sans trim rings. All I needed to do to the rims, was have them sandblasted, then I painted them the body color GB5 Bright Blue Metallic. I mounted 245/60/15 Goodyear Eagle ST tires on them and the car looked pretty cool after that. Only issue was my turning radius was reduced somewhat with the wider rims / tires on the front.

From what I read, it sounds like my 73 and 77 rims should have been large bolt pattern, and my car's drums and original wheels should have been small bolt pattern..

And I just don't recall ever noticing any difference in track width from front to rear.. And I looked at the car a lot! I never tired of looking at it lol.

The 5x4", small bolt pattern wheels only came on A-bodies, nothing else. All B/E bodies came with the 5x4.5" bolt pattern, so did the C bodies and the later R and FMJ bodies, most vans, all the half ton the trucks, you get the idea. Your '71 Challenger would have been BBP regardless of what brakes it had.

As far as the track width difference front to rear, it's not unusual. A-bodies have a much larger front to rear difference than the other Mopars of the era though. The E-bodies were pretty close to the same front to rear for track width.

rustycowll69 said
70-74 Challenger is an E-body, and they are all big bolt pattern. It's sister E-body car was the 70-74 Barracuda, which was also big bolt pattern.
I believe all early, and some later A-body 63-"about" 72 cars came with small bolt pattern, drum and 4-piston disk brakes. The gray area comes when Ma Mopar began to install the single-piston floating caliper disks around '73(I think). They changed to BBP on the A-body cars with the optional single-piston floating caliper installation. Of course, in order to have BBP rear wheels to match, those cars had to come with BBP rear axles. I THINK, they came with the so-called 8-1/4" rear axle. I don't think there ever was an OEM A-body BBP 8-3/4" rear axle. I believe at some point, maybe '75 they ran out of all the SBP drums, and axles and ALL the last A-bodies came with just BBP.

The A-bodies all had the 5x4" bolt pattern up through 1972, drum or disk. In 1973 the disk brakes were redesigned to be more uniform across all the car platforms, using single piston calipers and the same rotors, wheel bearings, and upper ball joints. So, all of the A-bodies 73+ with disk brakes were BBP, and they could have either a 7.25" rear axle, which also came in BBP starting in 1973, or the 8.25 rear axle, which were all BBP. There was never a factory BBP 8 3/4 A-body rear axle, 1972 was the last year for 8 3/4's in A-bodies. The weird part was that the front drum brake equipped A-bodies continued to be SBP even after '73. The spindles changed, so they used the same large ball joint UCA as the disk brake cars, and larger wheel bearings, but the front drums stayed SBP. All of those cars had /6's and 7.25" rear axles. V8 cars all got disk brakes from 73+, so, they were all BBP cars. Even /6 cars with certain options got disks and the BBP rears, my /6 '74 Duster did. The SBP drums went away for sure in January of 1976, when a federal mandate kicked in and all cars went disk in the front.