Disc brake one more time

stu’s68furyiiirat

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Will this work on my 1968 Plymouth fury III someone told me that this will bolt up to my car

IMG_7036.jpeg
 
No, as others have said, it won't fit.
B/E-body LBJs have a smaller bolt spacing than C-bodies, so the spindles won't bolt to your LBJ/steering arms.
The BJ pin-taper sizing is also smaller on those cars.

There were guys perhaps 10 years ago discussing the use of C-body discs on the smaller cars, but it required some machining work to get the parts to assemble.
Then there's the whole discussion of spindle height, alignment specs, and steering geometry.
But you wouldn't get far enough to worry about that with that kit.

I really wonder how well that fits all the years/carlines shown, as some 62-65 A-bodies can have 9" drum brakes, and I've read that those parts are really small, smaller than what is used on the small 10" drums. And we use 11" drums.

IMO your best bet right now, due to our C-body calipers being NLA, is the kit from ECI Hotrod Brakes. (but it's $925)
It has only an 11" rotor, but uses larger-piston GM D-52 calipers, and claims 15-25% more braking than later B-body brakes (which is in the kit you showed).
And it uses no bearing spacers or other claptrap.

Chrysler Disc Brake Kits
 
I've got that ECI brake kit sitting in my room right now, the biggest reasons for me picking this kit were the fact that you can retain the original spindle, and that there are EBC bluestuffs available in the D-52 pattern; I fully intend to take my barge out to the occasional "arrive and drive" style of track day. D-52 pads are everywhere though, so lots of options to choose from. It uses rotors from a 1980 firebird, rockauto sells them. They seem to sell centric/fvp 12162025 rotors which by the pics, appear to have two bolt patterns so these have a chance of fitting over our wheel studs. If these are confirmed to fit, then it will save having to machine rotors to fit our PCD.
Worth noting however that the instructions say to have the calipers towards the rear of the vehicle, but this may result in having to fab up new brake lines as the factory lines go to the front, and there is no rubber line I know of that can reach from the front all the way across to the caliper without consulting a local hydraulic shop. The mounting brackets are symmetrical however, so you can mount them on backwards so the left caliper sits on the right corner, and vice versa which lets you mount the calipers towards the front. Might raise eyebrows, but it saves having to refab the steel brake lines.
 
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AAJ Brakes
is a good alternative
For $300 you get a caliper mounting bracket that bolts to the original spindle and bracket mounting hardware. Plus a list of what caliper, rotor, and hose you need to get.(All readily available)
Brackets for 14 and 15 inch wheels are available
 
Wish I heard about AAJ earlier. The ECI brackets are great, but definitely put a dent in the wallet getting it, and getting the calipers and other hardware off rockauto could only help so much.
 
AAJ Brakes
is a good alternative
For $300 you get a caliper mounting bracket that bolts to the original spindle and bracket mounting hardware. Plus a list of what caliper, rotor, and hose you need to get.(All readily available)
Brackets for 14 and 15 inch wheels are available
Presumably hte AAJ uses the stock hub/bearings/seal, after you remove the drum from it?
Do you know if it will fit behind a 14" wheel?
If so, that $300 is a great option.
 
That centric/fvp 12162025 rotor isn't a direct-fit, at least on paper.

The 11.16" dia give a bit of a chance that it will fit inside a 14" rim, but the 2.201" overall height puts the caliper outboard toward the rim. (15" wheel should be no problem?)
It doesn't specify what the 2nd bolt pattern is, it is visually larger bolts than the .457" and a smaller bolt circle - so perhaps it fits our .5 on 4.5".
The center hole needs enlarged a bit to our 2.81", but that's do-able with a die grinder and a carbide burr if you have the patience.

The .98 x 11.16" rotor size is in B-body territory, and not the later '75-newer one that is 11.75", but the prior/smaller-dia one.
Is it better than 11x2.75" drums we have? Probably, esp with the better-friction D52 pads that are available.
But with heavy braking, I'd be wondering how easily these rotors will warp due to their reduced mass compared to a C-body rotor.

This is for 79-81 Firebird, so only 3 years of usage and only that car (no Camaro, either). Presumably it was for the WS6 handling package.
That's a cult-classic car, but if you go this route might want to buy 3-4 sets of rotors and put them on the shelf just in case these go NLA!

Be aware that hte D52 caliper comes in 2 sizes, for the thicker and thinner GM rotors. One must make sure to get the right one. Sometimes the GM full-size cars use the thinner rotor, one must dig into the measurement page (like the one posted below) to make sure.
This rotor is for the rear of the car, so one cannot simply choose the front caliper and assume it will fit the thickness of the rear rotor. It might match, but must verify.

I will be evaluating this rotor a bit further for sure. It might be what I've been lookign for.



1738808553210.png
 
When I was hunting for rotors on Rockauto I did see that and note the diameter of the hole was almost the same size as the Durago BR5560 rotor that I got and ended up having machined, resulting in the total cost blowing out to even more than if I had just bought the Centric rotors straight from Rockauto and footing the extra cost of shipping from a different warehouse from the rest of my parts.
The BR5560 has a center hole diameter of 71.7mm, while the 12162025 from what I can find is 70.8mm. With the ECI hub, the BR5560 fit snugly on it, my wishful thinking is that one could still get away with a 70.8mm diameter but I'll need to check again if there's any wiggle room on the hub for it.
The reason I suspect the dual bolt pattern of the 12162025 would work was because when I had my rotors drilled, the holes ended up looking exactly like what was seen in the Rockauto pics.
Be aware that hte D52 caliper comes in 2 sizes, for the thicker and thinner GM rotors
Oh boy, wish I knew that. However, the ECI kit does specify what parts are used and even includes part numbers for the bearings too, all this available from Rockauto as well:
This conversion kit uses the following components:
Calipers: 1978-1981 Camaro/Firebird with 10 mm hose bolt connections.
Rotors: 1978-1981 ECI/Camaro/Firebird style rotor with dual bolt pattern, (4 ½” and 4 ¾” BC).
Bearings & Seals:
A2 Outer Bearings (same as stock) SKF #LM11949A6
A6 Inner Bearings (same as stock) SKF #LM67048
SKF Seal #17187
The rotor size may be smaller than the stock drum, but the ECI kit specifies a master cylinder with a 1.031 inch bore, versus the stock 1 inch bore, which sounds like it increases the applied pressure to match that of the drums at the cost of increased pedal travel. And to be honest I don't actually mind extra travel; I feel like the stock brakes are incredibly touchy as they are.
 
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