Wilwood disc brake kit for mopar A body but using B body spindles

-
duster731

duster731

young gun
Joined
Mar 30, 2010
Messages
1,495
Reaction score
65
Location
Venus Texas
Ok so I have stumbled across an issue..

I bought this Wilwood kit for my 73 duster

Wilwood Disc Brakes 140-11023 Wilwood Forged Dynalite Pro Series Front Disc Brake Kits | Summit Racing

but I am running 70’s B body spindles on the car part#3402638. Now the issue I have stumbled on are the Wilwood caliper mounting brackets, they do not work with the b body spindles. What are my options at this point? Will I have any other issues? I am also adding Qa1 uppers and all brand new suspension parts.

Another issue I foresee is where the Qa1 upper mounts on the left side (pictured below) the tube rides the frame wall and there is also a decent gap in between the bushing and the frame wall. Should I just grind it down so the tube does not touch that area?

IMG_3665.jpeg


IMG_3664.jpeg


IMG_3663.jpeg


IMG_3662.jpeg
 
That Wilwood kit is for an A-body drum brake spindle, and what you have there is a B/E body disk brake spindle. That Wilwood kit will simply not fit that spindle. You’ll either need a Wilwood kit for a disk spindle, or just the rest of the Mopar disk set up.

Your interference point in the UCA mount is common with tubular UCA’s, you can clearance the UCA mount so that the UCA will fit. It’s required with most tubular UCA’s and has been done by lots of folks

IMG_2999.jpeg


The gap between the bushing and the UCA mount will close when you properly torque the camber bolt, as long as the bolt doesn’t run out of threads which has been a problem with some aftermarket camber bolts.
 
The kit you bought is made for '65-'72 A bodies with 10" drum brakes. You have B body spindles on a '73 A body. Of course they're not going to fit. You need to either get the kit for the appropriate year B body spindles that you're using (are they disc or drum spindles? They're all different), or convert to the earlier A body spindles- but that would mean your new QA1 upper control arms have to go. They have the large upper ball joint, and the A body spindles for that Wilwood kit take a small upper ball joint.
Even if you somehow made the caliper brackets fit those spindles, you'll find the wheel bearings are a different size.
See if you can still exchange it for the correct kit.
Edit: I *believe* the kit you need is 1975 DODGE CHARGER Wilwood Disc Brakes 140-15465 Wilwood Forged Dynalite Pro Series Front Disc Brake Kits | Summit Racing , since those are B body disc brake spindles you have.
 
Last edited:
Professor Fate said:
The kit you bought is made for '65-'72 A bodies with 10" drum brakes. You have B body spindles on a '73 A body. Of course they're not going to fit. You need to either get the kit for the appropriate year B body spindles that you're using (are they disc or drum spindles? They're all different), or convert to the earlier A body spindles- but that would mean your new QA1 upper control arms have to go. They have the large upper ball joint, and the A body spindles for that Wilwood kit take a small upper ball joint.
Even if you somehow made the caliper brackets fit those spindles, you'll find the wheel bearings are a different size.
See if you can still exchange it for the correct kit.
Edit: I *believe* the kit you need is 1975 DODGE CHARGER Wilwood Disc Brakes 140-15465 Wilwood Forged Dynalite Pro Series Front Disc Brake Kits | Summit Racing , since those are B body disc brake spindles you have.
Click to expand...
Ha of course that is the one thing I missed. I guess I shall sell this kit and buy the right kit huh? It looks like that kit above is out of stock but I’m sure I can go ahead and buy the cross/drilled rotor brake kit that is in stock
PLYMOUTH DUSTER Wilwood Disc Brakes 140-15465-D Wilwood Dynalite Pro Series Front Disc Brake Kits with SRP Rotors | Summit Racing
 
72bluNblu said:
That Wilwood kit is for an A-body drum brake spindle, and what you have there is a B/E body disk brake spindle. That Wilwood kit will simply not fit that spindle. You’ll either need a Wilwood kit for a disk spindle, or just the rest of the Mopar disk set up.

Your interference point in the UCA mount is common with tubular UCA’s, you can clearance the UCA mount so that the UCA will fit. It’s required with most tubular UCA’s and has been done by lots of folks

View attachment 1716153595

The gap between the bushing and the UCA mount will close when you properly torque the camber bolt, as long as the bolt doesn’t run out of threads which has been a problem with some aftermarket camber bolts.
Click to expand...
Thank you sir. I will definitely get this done to avoid issues.
 
duster731 said:
Ha of course that is the one thing I missed. I guess I shall sell this kit and buy the right kit huh? It looks like that kit above is out of stock but I’m sure I can go ahead and buy the cross/drilled rotor brake kit that is in stock
PLYMOUTH DUSTER Wilwood Disc Brakes 140-15465-D Wilwood Dynalite Pro Series Front Disc Brake Kits with SRP Rotors | Summit Racing
Click to expand...
Just make darn sure you know what you've got for spindles before you order anything else.
You say you've got "'70s B body spindles", but make sure you know what year they are. '70-'72 spindles look nearly identical to the '73-later spindle, but the inner bearing diameter is different- and that kit won't work.
Honestly, I think your best bet would be to get the Stage 2 kit from Doctor Diff- all factory-based parts that were designed to work together, includes the spindles (knuckles), larger rotors than the Wilwood kit, and service parts are available at any parts store. No waiting 2 weeks for proprietary brake pads.
And at $600, it's almost half the cost of the Wilwood kit. One of the best bargains you'll find for an A body, and stellar customer service to boot.
Mopar 11.75" Front Disc Brake Kit (Stage 2)
And guess what else? This kit will work with your QA1 ucas, too; as it uses the large upper ball joint.
 
Professor Fate said:
Just make darn sure you know what you've got for spindles before you order anything else.
You say you've got "'70s B body spindles", but make sure you know what year they are. '70-'72 spindles look nearly identical to the '73-later spindle, but the inner bearing diameter is different- and that kit won't work.
Honestly, I think your best bet would be to get the Stage 2 kit from Doctor Diff- all factory-based parts that were designed to work together, includes the spindles (knuckles), larger rotors than the Wilwood kit, and service parts are available at any parts store. No waiting 2 weeks for proprietary brake pads.
And at $600, it's almost half the cost of the Wilwood kit. One of the best bargains you'll find for an A body, and stellar customer service to boot.
Mopar 11.75" Front Disc Brake Kit (Stage 2)
And guess what else? This kit will work with your QA1 ucas, too; as it uses the large upper ball joint.
Click to expand...
Exactly!!!

Yeah I’m away from all of my casting numbers, I’m not sure if those are ‘70-72 or ‘73 up but the bearing is different and it’s pretty much impossible to tell just by looking at the spindle
 
Professor Fate said:
Just make darn sure you know what you've got for spindles before you order anything else.
You say you've got "'70s B body spindles", but make sure you know what year they are. '70-'72 spindles look nearly identical to the '73-later spindle, but the inner bearing diameter is different- and that kit won't work.
Honestly, I think your best bet would be to get the Stage 2 kit from Doctor Diff- all factory-based parts that were designed to work together, includes the spindles (knuckles), larger rotors than the Wilwood kit, and service parts are available at any parts store. No waiting 2 weeks for proprietary brake pads.
And at $600, it's almost half the cost of the Wilwood kit. One of the best bargains you'll find for an A body, and stellar customer service to boot.
Mopar 11.75" Front Disc Brake Kit (Stage 2)
And guess what else? This kit will work with your QA1 ucas, too; as it uses the large upper ball joint.
Click to expand...
The casting numbers are listed above on what spindles I have. I sold 2 OEM brake kits and the point of this conversation is simply for performance. At this point I think it’s best to sell the kit to buy a Wilwood kit that will work with my application. I’ll measure my bearing size on the current setup and go from there. Thank you for the info
 
duster731 said:
The casting numbers are listed above on what spindles I have. I sold 2 OEM brake kits and the point of this conversation is simply for performance. At this point I think it’s best to sell the kit to buy a Wilwood kit that will work with my application. I’ll measure my bearing size on the current setup and go from there. Thank you for the info
Click to expand...

If performance is your concern, the 11.75” Mopar disk set up will stop better than that Wilwood kit. The later factory 2.75” diameter piston calipers with a 11.75” rotor generate more stopping force than the 4 piston Wilwoods. Brand name aftermarket doesn’t always mean higher performance.
 
duster731 said:
The casting numbers are listed above on what spindles I have.
Click to expand...
Casting numbers don't necessarily equate to a part number- the same raw casting can be finish machined into several completely different part numbers for different applications.
 
Professor Fate said:
You might want to read post #40 in the following thread for some unbiased first-hand experience in this:
Aftermarket brakes for a 70 Dart?
Click to expand...
The current situation I’m in is for the same amount of money I can go down the street and pick up the Wilwood brake kit from Summit (employee discount) compared to spending $100 for shipping from Dr. diff. So I have to think about this.
 
What is most important?
a) Kit that fits
b) Kit that stops
c) Kit that you can go buy brake parts over the counter later (such as pads)
d) Brand prestige

I installed 1973 disc brake spindles on my 1972 Duster to bolt on all the factory correct style 1973 11” power disc brake system with rear drums, with correct single diaphragm 10” booster, 4 bolt master cylinder, and OEM style proportioning valve and have zero complaints. Ok, one complaint, 4 bolt master commits me to a very specific brake booster, no modern booster substitutes, but that’s my only issue, and a rebuilt booster fixed that, but it was a month long search. Otherwise, due to being just OEM replacement parts, they all just fit as they should and worked properly together, from RockAuto.

I have bought parts from Dr Diff, not brake parts, but rear differential rebuild parts, and guess what I didn’t have to do, rebuy those parts, because all the parts were right for my application, 489 SureGrip. Dr Diff does a lot of business with members on here because he knows what it takes to work for their application, as long as said application isn’t a total Frankenstein with no clue what is bolted to it. At that point one needs to just start over with factory correct…. Ditch the B body parts.

In my experience rebuilding my 1972 Duster, the biggest struggles I went through were pinion angle, driveshaft length, rear brake shoes, rear axle brake lines, rear axle brake T fitting and hose, and rear wheel offset. I bought axle shims twice, driveshaft twice, rear brake shoes twice, rear axle brake lines twice, rear axle brake T fitting and hose twice, and rear wheels twice. I would have been ahead to buy an A body 8-3/4 and rebuild it instead of entirely rebuilding and staying committed to the B body 8-3/4 that was in it when I bought the Duster. Oh, and it has a 7260 yoke on the pinion because I accidentally stayed committed to it when I replaced pinion and used crush sleeve instead of crush sleeve eliminator… good thing I don’t race… but that would be yet another revisit in the future.

I can not stress this enough, ditch the B body spindles on your A body car and buy A body spindles correct for whatever application you have and brakes you plan to equip it with, you are already buying twice because of it…

And things can be worse. The first three months I had my car completed and drivable this summer, after a 2.5 year rebuild, it was not entirely enjoyable because I was chasing driveline vibrations!!! And it took that long to figure it all out just to spend another $1000 sorting it out… all because a B body rear axle was installed. Since the pinion angle was set wrong when perches were moved and shimming affects the driveshaft length and that affects angles… I was locked in a battle of numbers and vibrations…
 
Last edited:
Looks like you got the wrong kit.
 
You must log in or register to reply here.
-

Back
Top