What disk brake upgrade for a 74 duster, not Wilwood

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Ozyduster

Ozyduster

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I have a 74 duster in Australia and will be doing a 6.4 hemi swap. I potentially have to upgrade the front disk set up, however is there a standard brake upgrade or all after market like wilwood? As my car will be engineered, some engineers dont like engineering after market products with the brakes.
So my question is, is there a mopar upgrade that is from a standard car?
Also all the standard rebuild kits look to be rubbers only do they not sell the pistons in kits as well?
 
well the standard "Add disks to your A body with drums" set up is the later claw slider caliper disk set up used on later 70s US A/MFJ body cars

now that is just a slightly bigger version of what you get on a VJ valiant a Girling Lockheed style single piston caliper on a claw like bracket

you can buy the parts from rockauto

and when i say bigger i mean that the caliper is about 1/16 of an inch different so it won't fit onto an Aussie claw slider bracket used on the VJ VK.

i.e the VJ caliper is local and you can get some off an Aussie Val. id do that and bolt them to the US stub axle and use a US hub/rotor


other option would be second hand 4 pot calipers and rotors off say a 68 barracuda with disks but expensive and hard to find and rotors work on small inner bearing stubs as far as i know.... if your duster has disks currently it has a stub with an inner taper for a bigger inner hub bearing than an Aussie valiant uses.

you could fashion something or buy a kit that uses viper calipers... at least its all mopar

keep in mind that your upper ball joints are the bigger ones (don't fit aussie stubs)
if you already have disks on the car the stub axle you have has a wider taper for the inner hub bearing so Aussie rotors won't fit as they are small inner bearing rotors.
you could use Aussie calipers but you'd need US rotors

alternatively you can fit US stuff to an aussie stub, the caliper brackets and caliper will fit
but your need the inner bearings sleeves from Dr Diff to use US rotors and you'd need aussie upper arms and balljoints or you'd need to ream out the upper ball joint taper to use the 74 upper arm and balljoint currently on the car
.
I guess the first thing i should have asked is what are you upgrading from and what do you want to achieve

your modern hemi is probably lighter than what was there previously

and if it has disks already i'd look to get them working right, designed for narrow crossply equipped 70s car. with radial tyres, get some proper proportioning in place first and see how ya go

otherwise

Brakes :: Front

you could try Home - Hoppers Stoppers Custom Brake Upgrades

other option is sumitomo calipers off a landcruiser hilux 4 pot caliper with the same mounting as a valiant some messing to convert metric holes to imperial sized mounting bolt and you need imperial to metric brake pipes.. i can supply details


Dave
 
What's wrong with the stock stuff that it won't work for you? It's very effective.
 
RustyRatRod said:
What's wrong with the stock stuff that it won't work for you? It's very effective.
Click to expand...
Nothing
the Slider calipers, kelsey pin style or girling claw slider style work well
provided the brake proportioning is addressed.
id rather have 9 inch drums at the rear but that seems to be only me... :)
and provided you have an appropriate bore for the master all should be well.
 
Dave999 said:
well the standard "Add disks to your A body with drums" set up is the later claw slider caliper disk set up used on later 70s US A/MFJ body cars

now that is just a slightly bigger version of what you get on a VJ valiant a Girling Lockheed style single piston caliper on a claw like bracket

you can buy the parts from rockauto

and when i say bigger i mean that the caliper is about 1/16 of an inch different so it won't fit onto an Aussie claw slider bracket used on the VJ VK.

i.e the VJ caliper is local and you can get some off an Aussie Val. id do that and bolt them to the US stub axle and use a US hub/rotor


other option would be second hand 4 pot calipers and rotors off say a 68 barracuda with disks but expensive and hard to find and rotors work on small inner bearing stubs as far as i know.... if your duster has disks currently it has a stub with an inner taper for a bigger inner hub bearing than an Aussie valiant uses.

you could fashion something or buy a kit that uses viper calipers... at least its all mopar

keep in mind that your upper ball joints are the bigger ones (don't fit aussie stubs)
if you already have disks on the car the stub axle you have has a wider taper for the inner hub bearing so Aussie rotors won't fit as they are small inner bearing rotors.
you could use Aussie calipers but you'd need US rotors

alternatively you can fit US stuff to an aussie stub, the caliper brackets and caliper will fit
but your need the inner bearings sleeves from Dr Diff to use US rotors and you'd need aussie upper arms and balljoints or you'd need to ream out the upper ball joint taper to use the 74 upper arm and balljoint currently on the car
.
I guess the first thing i should have asked is what are you upgrading from and what do you want to achieve

your modern hemi is probably lighter than what was there previously

and if it has disks already i'd look to get them working right, designed for narrow crossply equipped 70s car. with radial tyres, get some proper proportioning in place first and see how ya go

otherwise

Brakes :: Front

you could try Home - Hoppers Stoppers Custom Brake Upgrades

other option is sumitomo calipers off a landcruiser hilux 4 pot caliper with the same mounting as a valiant some messing to convert metric holes to imperial sized mounting bolt and you need imperial to metric brake pipes.. i can supply details


Dave
Click to expand...
Really appreciate the detailed break down!!!! Thanks for the tip on the rotars as would of thought the Ozy a body the same. If engineer is happy with stock disks ill stay with them and just rebuild with new rotors, braided lines etc. Currently my duster is a 74 and just has the standard single pot calipar. I have a 8,3/4 that currently is getting rebuilt and shortened. We will potentially fit Ozy ford disks as easier to get and same stud pattern as mopar. Forgot dr diff does all the brake stuff as purchased his spring offsets
 
and with an 8 3/4 on the back you can use aussie falcon (mid-70s-mid80s) rear disks

the caliper bracket is flat plate and can be sloted to fit without puling the axles shafts and re drilled to the pattern for the 8 3/4 back plate
and the similarities in handbrake cable lend themselves to easy conversion
let me see if i can find the article
 
Dave999 said:
Nothing
the Slider calipers, kelsey pin style or girling claw slider style work well
provided the brake proportioning is addressed.
id rather have 9 inch drums at the rear but that seems to be only me... :)
and provided you have an appropriate bore for the master all should be well.
Click to expand...
Do you run a brake proportioning valve?
 
Dave999 said:
and with an 8 3/4 on the back you can use aussie falcon (mid-70s-mid80s) rear disks

the caliper bracket is flat plate and can be sloted to fit without puling the axles shafts and re drilled to the pattern for the 8 3/4 back plate
and the similarities in handbrake cable lend themselves to easy conversion
let me see if i can find the article
Click to expand...
Yep spot on, my diff guy straight away said to use the ford mid 70s disks as dirt cheap etc etc. Looks like you know your Mopar a bodies world wide haha.
 
yeah I have an RT charger with webers and it had worn out and crusty VH Kelsey pin slider 1 pots on the front with 9 inch drums on the back

short arse car. light in the rear little overhang compared with a dart....The rear would try to overtake my right hand shoulder in a massive broadside skid if i hit the anchors in the wet

after visiting the centre of a rotary/roundabout, ending up like a display or piece of art on the grass in the middle for all to see, near work one night, i decided enough was enough

i took the RT/ VK valiant (under the dash hidden behind the sound deadening) proportioning valve
fitted it
new tyres all round
and i swapped to brand new old stock VJ calipers which I prised out of the hands of a holden dude.

i can now use both feet on the brake if necessary(not been necessary) :) and the car pulls up true

the same could be achieved with a good quality adjustable bias from any local or US source of good parts.

switch off rear and then add in until breaking performance is too your liking and car doesn't scare you by trying to turn round at inappropriate moments.
 
Dave999 said:
yeah I have an RT charger with webers and it had worn out and crusty VH Kelsey pin slider 1 pots on the front with 9 inch drums on the back

short arse car. light in the rear little overhang compared with a dart....The rear would try to overtake my right hand shoulder in a massive broadside skid if i hit the anchors in the wet

after visiting the centre of a rotary/roundabout, ending up like a display or piece of art on the grass in the middle for all to see, near work one night, i decided enough was enough

i took the RT/ VK valiant (under the dash hidden behind the sound deadening) proportioning valve
fitted it
new tyres all round
and i swapped to brand new old stock VJ calipers which I prised out of the hands of a holden dude.

i can now use both feet on the brake if necessary(not been necessary) :) and the car pulls up true

the same could be achieved with a good quality adjustable bias from any local or US source of good parts.

switch off rear and then add in until breaking performance is too your liking and car doesn't scare you by trying to turn round at inappropriate moments.
Click to expand...
O that makes sense, yep my hq holden used to do that, try and over take its self if on the brakes hard. Body work on the duster nearly completed and will have it back soon to start on all the suspension and running gear. Most of it is sorted, just figuring out how much to take off the diff is the next step.
 
I'm a huge fan of Wilwood, and have used them many times. I prefer 4 wheel disc brakes as well.

If you want something other than stock up front, but it has to be Mopar, i'd look into Viper Brakes up front.

Check this site out. Cass has a lot of brake kits and options for you to choose from.

Brakes :: Kits and Assemblies - page 2
 
Viper Kit Check your caliper clearance as most 18" wheels will clear, but poorly designed 17" wheels may not clear.
 
i'm sure wilwood are great but the issue in Australia is that the rules dictating what you can fit to your car differ in each state or territory and you have to get your modification approved by a qualified engineer in order to allow it to be legal with that states version of the Department of transport even something as minor as a change of track at the front can cause issues if it goes out of the bounds that were set by the manufacturer of the car

i.e in the US you would need to get someone from SAE to do a custom report on your specific car and submit it to a 3rd party in the local department for vehicles and roads, to approve your addition of aftermarket brakes

i.e you spend more on the paperwork than on the actual purchase and fitment

hence if you are engineering a motor swap keeping some of the rest of it nearer standard can help your wallet and sanity

things may have changed i last lived there 20+ years ago

hence i doubt this decision is being driven by a dislike of Wilwood products its more likely a dislike of paperwork and bureaucracy.

in many US states you have it easier, you can build what ya like

Australia and Europe (france and germany mainly) not so much

liking Wilwood and being in a position to fit Wilwood, two different things

and the calipers without rubber seals on the pistons would not be approved


Dave
 
Dave999 said:
i'm sure wilwood are great but the issue in Australia is that the rules dictating what you can fit to your car differ in each state or territory and you have to get your modification approved by a qualified engineer in order to allow it to be legal with that states version of the Department of transport even something as minor as a change of track at the front can cause issues if it goes out of the bounds that were set by the manufacturer of the car

i.e in the US you would need to get someone from SAE to do a custom report on your specific car and submit it to a 3rd party in the local department for vehicles and roads, to approve your addition of aftermarket brakes

i.e you spend more on the paperwork than on the actual purchase and fitment

hence if you are engineering a motor swap keeping some of the rest of it nearer standard can help your wallet and sanity

things may have changed i last lived there 20+ years ago

hence i doubt this decision is being driven by a dislike of Wilwood products its more likely a dislike of paperwork and bureaucracy.

in many US states you have it easier, you can build what ya like

Australia and Europe (france and germany mainly) not so much

liking Wilwood and being in a position to fit Wilwood, two different things

and the calipers without rubber seals on the pistons would not be approved


Dave
Click to expand...
Spot on mate!! Engineers will not pass a lot of willwood options for whatever reason. Lot easier to get standard issue brakes over the line. Hopefully just need to upgrade the rears and rebuild the fronts
 
roccodart440 said:
how in depth are these communist assholes inspecting every car that passes through their shop? Do they really know what they are looking at?
Click to expand...
Hahha, its because my car isnt yet registered. It will be registered with either a Hemi or a turbo 318. So engineering company then tells me what they require to sign it off. Brakes, chassis stiffening etc and complying to the newer motor emissions if hemi. The engineering company build serious cars, st legal 1000hp cars etc etc. So they know what they are talking about. Not just a pen pusher. Then with their paper work i go down and register car. When girl at desk says no such thing as a hemi duster i hand paper work over. If hwy patrol pull you over your car has a mod plate so nothing ilegal about the car etc. I know you guys see this as control but also stops morons building some completely unsafe car and killing themselves or someone else.
 
Ozyduster said:
Hahha, its because my car isnt yet registered. It will be registered with either a Hemi or a turbo 318. So engineering company then tells me what they require to sign it off. Brakes, chassis stiffening etc and complying to the newer motor emissions if hemi. The engineering company build serious cars, st legal 1000hp cars etc etc. So they know what they are talking about. Not just a pen pusher. Then with their paper work i go down and register car. When girl at desk says no such thing as a hemi duster i hand paper work over. If hwy patrol pull you over your car has a mod plate so nothing ilegal about the car etc. I know you guys see this as control but also stops morons building some completely unsafe car and killing themselves or someone else.
Click to expand...

Most states have inspection regs.

So once you make it through that inspection, couldn't you just do what you wanted?
 
yeah but then the car in front of the cop, doesn't match the recorded modifications so it invalidates your insurance and roadworthy test if needed in that state

i.e they throw 2/3rds of the book at you

the last 1/3rd would be no licence

gets expensive and you'd probably be getting the bus from then on... at least for a while.

some states will tow and impound and may move to destroy an illegal car depending on what you did to be in front of the cops/court in the first place.

they don't mess about

dave
 
What cop pulls your wheels off and checks your brakes on the side of the road?

I guess follow the laws if it's that strict. I'm glad I don't live in Aussieland, especially after seeing what they did to you guys since 2020.
 
roccodart440 said:
What cop pulls your wheels off and checks your brakes on the side of the road?

I guess follow the laws if it's that strict. I'm glad I don't live in Aussieland, especially after seeing what they did to you guys since 2020.
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I think he is a bit off the mark. If i for example changed the brakes so they are not legal if i had a big crash insurance may not cover. They try scare you with the if someone dies you are in the **** etc. Driven heavily modified cars my whole life, been done for too low and thats it, put back to correct height and went through the pits then dropped it again. They only impound your car if excessive speeding or doing burnouts etc. Not for unroadworthy etc. Dont beleive everything u read about Covid here, usa heavy right used us as a scare monger for usa and lied like said we had prison camps which was false. Simply had to quarantine for two weeks if you wanted to go interstate. The quarantines were usually hotels rented by government. However victorian state goverment got heavy handed with lock downs where as all other states were fine. To be honest when i traveled to usa and canada as soon as flights opened i felt more restricted there
 
roccodart440 said:
What cop pulls your wheels off and checks your brakes on the side of the road?

I guess follow the laws if it's that strict. I'm glad I don't live in Aussieland, especially after seeing what they did to you guys since 2020.
Click to expand...
None of them
but the suspicion is enough.

I lived in NSW for 5 years a long time ago now, i'm a white european. I had a number of cars all of which were none standard in one way or another and all of them might be considered of a style that marked me out as coming from a greek lebanese or italian background.

I got ticketed twice for having a towing hitch/ball on my car that obscured the licence plate. didn't matter that it was standard factory fit tow bar on a valiant with a standard licence plate in the correct position

they pulled me over, and maybe when they spoke to me i wasn't what they expected but they still ticketed me.
local cop pulled me twice in 2 weeks for the same thing.

country NSW/ACT boarder there is a big police collage Goulburn is the place

the freeway splits and has a huge central median with trees and bushes. ideal for cops to hide in with vehicle

driving that area at 2am one night, in a hurry, and on a deserted road out of nowhere a pickup truck (UTE) covered in hunting lights CB antennas etc past me at what must have been 120MPH

being an idiot i upped my speed to maybe 90 thinking, he's right, why hang about out here in the middle of nowhere in the middle of the night still a good few hours from my home

I carried on for maybe 3 or 4 miles and he was long gone...
nothing in front nothing behind

At which point from a place where i assumed nothing behind me
the cop car switched on full head lights and blue flashers
that one was expensive
i tried to call them out bad move
i.e you are breaking the law by driving behind me with no lights on

yeah mate but i'm not the one whos getting points removed and a fine am I.

Don't mess with NSW police

so my experience has obviously coloured my view :)

dangerouse and standard no problem
My car passed its roadworthy with noisy wheel bearings and ripped engine mounts

modified and safe you are in some cases a target for bored cops

Or you were it may be totally different now :)

at the time sydney police had 2 pickup trucks with rubber bumpers specifically for pushing cars off the road that were parked in a position they didn't like....! which always had me baffled and amused :)

Dave
 
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