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71 B body Front Disc Brake Rotors or Conversion?

JG71B

JG71B

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Having no luck finding the right rotors.....tried a member here, forn73 up. Classic Ind lists as 70-72 b body, as does RockAuto. Is there an aftermarket for stock application? A conversion I can use or buy? Appreciate the help
 
You can use 73 and lates A body setup ( which are plenty ), including spindles change and you are done. Sure if your cars is already front disc from factory would be nice to keep them just like it came out, just that rotors are not common.

Search for a Rick Erenbherg (sp?) article called DISC-O-TECH and will find the parts needed with some options.

Dr.Diff get a set already made for that, based on factory Mopar parts from that article.
 
JG71B said:
Thanks but those are 11" conversion replacements. Factory is 10"
Click to expand...

"Precision machined 4130 cr-mo adapters are used to install common, inexpensive '73 and newer 10.95" Mopar A,B,E,F,M,J Body rotors on original '70-'72 Mopar B/E body disc brake knuckles.
Can also be used to install '78 Cordoba 11.75" rotors and caliper brackets."

Right from the description that they work for both. This only changes the bearing size, both rotors use the same bearing.

Factory standard is 10.95" the big ones are 11.75"
 
T2R9 said:
"Precision machined 4130 cr-mo adapters are used to install common, inexpensive '73 and newer 10.95" Mopar A,B,E,F,M,J Body rotors on original '70-'72 Mopar B/E body disc brake knuckles.
Can also be used to install '78 Cordoba 11.75" rotors and caliper brackets."

Right from the description that they work for both. This only changes the bearing size, both rotors use the same bearing.

Factory standard is 10.95" the big ones are 11.75"
Click to expand...
Now I'm confused.....71 uses 1.250" inner. 73 up uses 1.375" inner bearing. What would be my issue with the DrDiff kit I used?
 
JG71B said:
Now I'm confused.....71 uses 1.250" inner. 73 up uses 1.375" inner bearing. What would be my issue with the DrDiff kit I used?
Click to expand...

The adapter slides onto your 71 spindle so you can use the 73-up 1.375" inner bearing thus the rotors.
 
T2R9 said:
The adapter slides onto your 71 spindle so you can use the 73-up 1.375" inner bearing thus the rotors.
Click to expand...
Yes sir. That is what I put on yesterday and am getting a grinding noise
 
I am confused at what your doing. In your original post you were looking for 71 rotors and cannot find them. So you already have the adapters and tried 73 rotors and getting a grinding noise?
 
T2R9 said:
I am confused at what your doing. In your original post you were looking for 71 rotors and cannot find them. So you already have the adapters and tried 73 rotors and getting a grinding noise?
Click to expand...
Lol my bad man.... out of the three sets I have I put a set of rotors on yesterday, all were listed for 71 but all have the larger inner bearing diameter and I happen to have the dr diff spindle kit on hand just in case I ran across this. Sleeves went on fine, the bearings and rotors went on fine but, taking it down the road it sounds like the sleeves are spinning on the spindle themselves. I'm at the point now I just want oem. Someone just mentioned to me that somewhere along the line they updated the bearing and the race is thicker but this is new to me
 
OK, I have not heard of an issue with those sleeves but I can believe that. I used the Dr Diff 73 spindles on my 71 as it was a drum brake car and they fit and function just fine.
 
T2R9 said:
OK, I have not heard of an issue with those sleeves but I can believe that. I used the Dr Diff 73 spindles on my 71 as it was a drum brake car and they fit and function just fine.
Click to expand...
Got 'er button up. 1/2 ignorance 1/2 wrong part# at the part store. All feels like new. Appreciate the help!
 
JG71B said:
Now I'm confused.....71 uses 1.250" inner. 73 up uses 1.375" inner bearing. What would be my issue with the DrDiff kit I used?
Click to expand...


Have you called and talked to Cass, AKA "Dr. Diff"? Best source for your situation and he makes it right with his customers.
 
Nacho-RT74 said:
You can use 73 and lates A body setup ( which are plenty ), including spindles change and you are done. Sure if your cars is already front disc from factory would be nice to keep them just like it came out, just that rotors are not common.

Search for a Rick Erenbherg (sp?) article called DISC-O-TECH and will find the parts needed with some options.

Dr.Diff get a set already made for that, based on factory Mopar parts from that article.
Click to expand...

The Dr. Diff spindles (not sleeves) are good for this. The geometry is correct for a b body. I used them on my '72. Uses 73 and up rotors and bearing sets.
 
yeap... 73 and lates Rotors and related parts are the same to A, B and E bodies ( but spindles and UCA on certain combos )... even M and F. Can't talk about C bodies thought
 
TopBanana72 said:
The Dr. Diff spindles (not sleeves) are good for this. The geometry is correct for a b body. I used them on my '72. Uses 73 and up rotors and bearing sets.
Click to expand...
TopBanana72 said:
The Dr. Diff spindles (not sleeves) are good for this. The geometry is correct for a b body. I used them on my '72. Uses 73 and up rotors and bearing sets.
Click to expand...

These are the exact ones I used for (72 and below b bodies.) Worked perfectly. I like that it is the thicker beefier spindle at the base.

Mopar Reproduction Disc Brake Knuckles for A/B/E Bodies (doctordiff.com)
 
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