I've got a pair of backing plates that have Ford script and part number "CIAA-2213-A" on one and "CIAA-2214-A" on the other. They are for, I believe, 11" brakes, hopefully right & left, and I'd like to know what they came off of and how wide a shoe they're designed for. I'm ***uming different width shoes required different offset backing plates. Can anybody help me out ? Thanks, -Bob
Correct me if I'm wrong, but don't all 9" backing plates have the same backspacing? I believe the shoe width is made up with the drum width and axle spacing.
Not always. Take for instance the 1/2 ton trucks. From '57-'72 Ford used the 9" rear. All of them have the same spring spacing and the same drum to drum measure (that means they have the same width flange to flange) 61". They did through those years have different width brakes and that was made by backspacing the backing plates. I have a '68-'72 with the widest of that series brakes and the backing plates are "backspaced". I just bought a '57 from another HAMBer and the backing plate is just about flat. I can't verify all applications but at least for this one the wider brakes were accounted for based on the backing plate.
You are correct sir! C = Decade = 1960's 1 = Year = 1961 A = Line = Galaxie/Full size p***enger cars A = Engineering Dept. = Ch***is EDIT: These would be for 11" x 2.5" brakes.
Are you sure? I know the axle flange to the housing flange distance is not the same on all 9" and that is where they make up the difference in the drum width, with the housing flange to housing flange being the same. I could be totally wet, but take a look at both of those backing plates you have and see if they're different. Like I said, I could be wrong, but I'd be curious what you find!
I seem to recall getting into trouble with a couple of late 50s 9" backing plates being different offset, so the measurements I made for the axle and drum were off by 1/4". I sure would not count on all of them being the same.
I measured some more. For the two 1/2 ton rears they both measure 56.5" flange to flange and as I said before they both measured 61" drum to drum. As you can see in the picture though, the backing plates are clearly different. The '68-'72 has an offset of 1-1/4" and the '57 has an offset of about 1/2" plus about 1/4" for the thickness of the flange so 3/4". The difference is 1/2" on these measurements. NAPA lists the '72 brakes as 2-1/4" and the '57 as 1-3/4" or 1/2" total. My guess is that this is true for all backing plate spacing. Think about it this way. If all backing plates were the 3/4" back space like the '57 I have. The backing plate bolts to the flange so is always in the same relationship with the bearing. The only way they then could have wider brakes is to have the axle stick out past the bearing more, or have more back spacing on the backing plate. I think the only reason they had different flange to flange (drum to drum) was only to fit the width of the different cars properly.
MNFalcon is correct. I have a 57 rear, axle flange to flange is 57 1/4. I put on the wide TBird brakes (backing plates, etc) and the axle flange to flange is still 57 1/4. The difference in brake shoe width is made up by the backing plate offset.
You guys are confusing brake offset with back spacing. Offset is from the axle face to the housing flange. Back space is brake width minus offset. Make sense?
Thanks for taking the time MN Falcon, good info. It's scary that one of the major rear end manufacturers that sells the complete brake kits told me that the backing plate spacing on 9" rears are all the same. They probably only sell one back space, so thats what they say.
Sorry, when I said "offset" I was talking about a physical offset that I saw in the backing plate. I did not know that offset was an official terminology used for the distance between the axle face and housing flange. As I surmised above then, the offset (axle face to housing flange) would likely be very similar on all 9" rears, as you really wouldn't want more axle sticking out past the outer bearing, as that would make the axle weaker. IMHO I will try not to mix my terminology in the future.
Just wondering why you would use 2.25" shoes? What years had that size? '61 Galaxie shoes (60-62 are the same) are not that expensive. They range from $14 to $30 per set depending on whether you want riveted or bonded.
The spacing between the housing flange and the axle flange changed in late '66 or early '67. I had some mismatched parts, and needed to find new brakes that would fit the earlier housing. Stuff off a '66 Galaxie fit my '59 housing. Of course, the previous housing was a '67..... ain't that always the way?
"Just wondering why you would use 2.25" shoes? What years had that size? '61 Galaxie shoes (60-62 are the same) are not that expensive. They range from $14 to $30 per set depending on whether you want riveted or bonded." Good point - I just wanted to use a real good set-up I had on hand because I'm trying to see how "ecconomically" (i.e. cheap!) I could build a quality, traditional rod, as I did back in the early 60's. I may just go ahead and get & use some 2-1/2" shoes. Thanks for everybody's input. The unselfish sharing of knowledge on HAMB never ceases to amaze me. It also amazes me how much I DON'T know after all these years !
I was faced with $400 for brakes to fit my small bearing housing or $80 for big bearing ends with a set of nearly new truck drums that a friend gave me. Since I will need axles anyway, I took his drums and swapped my ends to get my brakes for under a bill. Being truck drums, late '70s I guess, they are 2.5" wide. HUGE for a 2400 lb. car. I plan to turn the flange off the back of the drum to make them look smaller. It's about an inch of cooling material I won't need. Should lose a few lbs, too.
Well if you're trying to be economical then it totally makes sense! I'm sure all of us here can understand that. (BTW If you look for shoes at a Napa, don't be alarmed if they list them as 11-1/32" diameter.)
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