8 3/4 Backing Plates

[R72Demon]

Were do you measure from on backing plates to know what size they are? I need to make sure I have the correct backing plates for A-body with 4" bolt pattern. Thanks.

 

[pettybludart]

Were do you measure from on backing plates to know what size they are? I need to make sure I have the correct backing plates for A-body with 4" bolt pattern. Thanks.

Lay the plate flat,and measure from the floor to center?I could be wrong?I,m pretty sure though.

 

[R72Demon]

Ok, thats kinda what I figured, but just wanted to make sure. Thanks.

 

[pettybludart]

Ok, thats kinda what I figured, but just wanted to make sure. Thanks.

I do have good backing plates off of a 72 demon 8 3/4,for 10x1 3/4 brakes.This is how I found out when I got my Moser axels for 10x2 1/2 brakes.Duh!Let me know if you need plates?Cheap!

 

[jiw700]

Lay the plate flat,and measure from the floor to center?I could be wrong?I,m pretty sure though.

i,m lost,what are you measuring for backing plates or drums?

 

[Small Block]

I'm with 700 on this one. Are you wanting to know the diameter for the drums? Bolt pattern will be irelevent. Clue us in. Thanks
Small Block

 

[pettybludart]

i,m lost,what are you measuring for backing plates or drums?

I believe he wants to measure them so he knows what size he has for buying parts?Shoes or drums.

 

[R72Demon]

I was just trying to find out what backing plates I have, since there is 10x 1 3/4 and 10x 2 1/2 plates.

 

[jiw700]

I was just trying to find out what backing plates I have, since there is 10x 1 3/4 and 10x 2 1/2 plates.

10" backing plates are 10"backing plates,1 3/4" and 2 1/2" are brake shoe width's.if i'm not wrong a-body rear sbp are 1 3/4" and new drums are still available,i just did mine a few weeks ago.

 

[metallidart]

I just measured my 10" a-body backing plates, and my 10" 2.5" backing plates. Laying a straightedge across the mounting flange, on the side of the shoes, from the straightedge to the raised part the shoe rides on is about 1/2 an inch on the a-body backing plates. On the 2.5" backing plates, it measures an even inch. Coupled with the difference in the axles (if I remember correctly the big bolt pattern axles are about 3/8 longer on the flange side) thats where the difference in shoe width comes from. I can post pics later if anyone needs them, I have to take the kids to the circus now.