Anybody got a spare set of the 2 1/2 inch rear backing plates? Destined for a 68 SB xr7
Just curiousā¦ are you racing?
If not, be careful, as changing this can make the rear brakes to over brake, causing rear lockup & possible accident. Bigger is not always better. Wheel cyl bore size should be considered, as they change depending on the car, motor & trans, and options. A manual brake adjustment valve is a probable item needed.
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Hey Bill, thanks for the FB. No, not a race car, just street with an unnecessary amount of horsepower, and commensurate braking. Say roughly to BB equivalent.
Last time I did this, I indeed added the adjustable proportioning valve, and could dial out early rear lock.
I tend to believe Maier on the RDB conversion being overkill, and think wide R4-S shoes should suit.
Vic Y. told me about this āupgradeā a few decades ago ( dang are we getting Old!) for his Track Cat.
Never found a set, nor found I needed it, but I was not racing.
I ended up putting the valve next to driver seat forward of the seat belt. Makes adjusting it easy on the fly. I can still lock up the fronts just before the rears. Might I suggest looking at Porterfield for compounds that will help alot!
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I think only station wagons and Shelbys used the wider brake shoes. The modern version uses later model Ranger rear shoes, a backing plate from the late 1990ās will do it. Like Bill says unless you are restoring one of the cars that used these originally you are unlikely to enjoy the results.
Vicās ears will be buzzingā¦ thus me pulling brakes from a junkyard 72 Ranchero around 1990 
. Was happy with the results in that particular instance 
Donāt think any of us would argue our cars were āover-brakedā with base drum brakes. I certainly needed a few changes of shorts.
Hi Royce. According Porterfield search, 2-1/2 rears came standard on ā68 427/428 Cougars.
That is incorrect. The shoes are the same size as any other V8 Cougar.
I concure with Royce!!
How about the books for years had the 69 & 70 front bearings swappedā¦
The internet is not the only place they were/are wrong about Cougars!
The plot thickensā¦
LOL the front brake shoes will not fit the rear despite what the internet says.
I have asked this for quite some time ago as well and the feedback i got from alot of people here is the same as been going on. Mostly 67 ford wagons offered these sized backing plates and brake setups. Which are almost impossible to find nowadays. I have gone on numerous forums to no avail to locate a pair as well. I am just going to stick to my original setup and possibly if i do find a pair i`ll play the lottery lolā¦
thanks
pat
OpenTracker has an 11ā kit:
Cobra Automotive offers similar, and still has 10ā dia kits up.
Parts yards should still be an option:
https://mustangsandmore.com//ubb/RearBrakesbySamGriffith.html
Was hoping someone was sitting on a pair.
To my understanding it was a standard upgrade on Shelbys and TransAm cars.
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I am surprised that no one has reproduced standard backing plates. I had to have mine welded on the pads where the edges of the shoes make contact.
Wonder if they recommend a different wheel cyl (size). Welding backing plates on 50 year old cars is a normal part of doing a correct brake job!
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there were at least 2 different sizes 1 3/4 and 2" on the early cougars. WCCC list both sizes of backing plates, shoes, and drums.
Cougars used 2" Shoes on the rear for big block cars either 390, 427 or 428. Not the 2 1/2" as the internet claims.
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The 11ā x 2.25ā kit wonāt fit 14ā wheels. Also, you lose 1 sq in of swept area.
The 10āx2.5ā backing plates were found on 1963-71 Fairlane SW and Rancheros.
My ā67 Race car setup came out of a 1967 390 Fairlane SW. I used 7/8ā wheel cylinders after the NOS Ford Shelby-size 13/16ā wheel cylinders started leaking (and couldnāt find any out of town). An adjustable proportioning value sets the front/rear bias. Initially, I ran the heavy finned rear drums but still managed to turn them blue due to the heat from heavy braking.
Based on my observation, the only difference between the 1969-70 2ā backing plates and the 2.5ā backing plates is the length of the anchor pin - itās slightly longer. I never found a source for new anchor pins. Theoretically, you could machine a new pin and use the 2ā backing plates. The finned drums are the same for 2ā or 2.5ā applications (Torino).
If you make an adapter ring to center the drum, the 2.5ā drums and shoes from a 1991 Explorer will fit. The 1991-94 Explorer 581 shoes have bigger rubbing tabs on the side of the shoes and help guide the shoe better.
Vic Yarberry