8 3/4 SBP 10x1.75” Drum Help*

[b-body fan]

Hmmm.. just spitballing but I’m guessing the axle shaft length is correct? I didn’t use OE style bearings either. Not that it makes a difference. I used green bearings from Dr Diff. Offset of the axle? I’m stumped..

 

[cudamark]

Looks far enough in your photo. The bearing cone needs to be pressed all the way to the stop. If you see a gap between the inner race and the stop/shoulder on the axle shaft, it wasn't pressed in far enough.

 

[b-body fan]

Here is a picture of an A body 8 3/4” backing plate. The flange offset is 1 7/16” or 1 3/8”, I would check the offset of your current backing plates to confirm that you have the correct backing plates. Did you get the complete set of 1.75” drums and backing plates together, or are these pieces that were put together separate? Most people don’t know anything about the small bolt pattern stuff, which is all I run on my A body cars. I have a few extra sets of everything if you find out you need any or all of the components to make up a complete set. Including the original style bell flanged drums.

View attachment 1716403983

1 1/16” flange to rub pad

1 23/32” Flange hight (Offset) and I guess we can call that 1 3/4”

Does that make them LBP backing plates?

 

[b-body fan]

I compared the old 2.5” setup that came off the car with LBP axles and the plates in question and they are both 1.75 flange offset

Clearly the plates are the problem here

Thanks to all for the responses and informative details.

 

[Dana67Dart]

Yep the plates are BBP (2.5 most likely)
You can not sit and A Body backing plate flat on a table like that. The bumps for the e brake cables raises it up.

 

[Swinger 340]

I compared the old 2.5” setup that came off the car with LBP axles and the plates in question and they are both 1.75 flange offset

Clearly the plates are the problem here

Thanks to all for the responses and informative details.

View attachment 1716404443

View attachment 1716404444

Instead of saying the plates are the problem, why not just buy the drums to match the plates you have, if I'm ready the story correctly.

 

[cudamark]

Because they don't make 10 X 2 1/2 brake drums with the small bolt pattern.