Front Disc Brake Conversion Confusion

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SpeedThrills

SpeedThrills

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I know there are a zillion threads on FABO about front disc brake conversions. They mostly all regard unique situations. I couldn't come up with answers to my situation. So here goes:

I have 74 Dart Sport (cloned onto a 70-71 Duster) it's a slant car with 9" drums and SBP. I've replaced the rear brakes with the 9" Ferd I'm installing. They're 9.5" drums that I have found out are GM. I have no idea why, I discovered this after I bought the D150 pro street truck it was in for parts. (I bought 4 1/2" BP wheels and found they wouldn't fit. I'm redrilling the axles.)
Anyhow, I need to upgrade the 9" fronts to A) increase stopping power, and to B) change the BP to 4 1/2.
I'd like stay with something on the lighter side, as it is a street/strip car. Wilwood has this kit:Wilwood Disc Brakes - 1974 Dodge Dart Demon All - Front Brake Kit No.: 140-15465
But it says I need to have a factory disc spindle. Also needs master cylinder, adjustable proportioning valve, and maybe other stuff?
PST has this kit:i-23158284-front-manual-disc-brake-conversion-kit.html It appears to have everything, including master cylinder, adjustable proportioning valve, control arm, spindles.
I plan on rebuilding the front suspension. This seems to have most of the replacement suspension parts included. I don't know the weight, but the completeness is appealing.
Is the PST the ticket? Any other options?
Actually, I wouldn't mind 10" drums, probably from a B-body to get the BBP? That should be cheaper than the PST, but I would have to get a MC, pro valve and?
But again, the completeness of the PST works for me.
 
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DrEamer said:
The other option is the Doctor Diff kit, very good after the sale service/tech as well.
10.95" Front Disc Brake Kit (Stage 1)
Click to expand...
Thanks, Doc. I'll have to call them (and PST) for details.
They look the same, except Dr. Diff has no MC for A body w/ man brakes (mine), no control arms and ball joints, and no adjustable proportioning valve, unless the distribution valve is for that purpose. If that's the case, it won't work because my GM rear drums will require adjustable F-R bias.
The $435 goes up a bunch when I add the items PST includes.
PST has free shipping, Dr. Diff $293.00!
 
Looks like Scarebird kits only fit up to 72. They show a couple different kits. I'd have to call to see what I need to do to make one work. Mopar There are two kits that come close. It's not clear, but it looks like one is for SBP and one is for BBP. Then, it still needs the MC and adjustable proportioning valve.
 
SpeedThrills said:
I'm definitely leaning towards the PST kit. Anyone have experience with it?
Click to expand...

PST is a site vendor, that I believe gives forum members a 10 percent discount, as to their quality, I don't know. The reason I brought up Doctor Diff, is because I have bought quite a bit of parts from them, and I know them to work. Also, Cass has answered any questions before, and after the sale. I'm sure the PST stuff is all right.
 
DrEamer said:
PST is a site vendor, that I believe gives forum members a 10 percent discount, as to their quality, I don't know. The reason I brought up Doctor Diff, is because I have bought quite a bit of parts from them, and I know them to work. Also, Cass has answered any questions before, and after the sale. I'm sure the PST stuff is all right.
Click to expand...
Thanks, Dr Reamer. I understand what you're saying. I can certainly appreciate good help from a vendor.
I'm up in the air on this one. I'm going from Wilwood and the related parts (most expensive, I think), and redrilling my 9" drums for my Prostars 4 1/2 BBP and using an adjustable proportioning valve (least expensive, probably).
 
Mopar Action featured a brake swap years ago that used your knuckle. You'd use the 11.75" factory rotor and use a 4 piston caliper. Not sure if it was early Viper or wilwood. Andy F might have been the source for the caliper bracket. Might be worth looking into as it uses stock rotors.
 
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sccachallenger said:
Mopar Action featured a brake swap years ago that used your knuckle. You'd use the 11.75" factory rotor and use a 4 piston caliper. Not sure if it was early Viper or wildwood. Andy F might have been the source for the caliper bracket. Might be worth looking into as it uses stock rotors.
Click to expand...

I think Doctor Diff may have bought the rights from Andy F for the Viper caliper brackets.
Viper Caliper Mounting Brackets for Mopar DRUM Knuckles

Also, he has a kit to use GM calipers that might be easier to source parts. Neither bracket is kit is super cheap at $200 of more.

https://www.doctordiff.com/front-disc-brake-caliper-brackets-for-11.75-on-drum-knuckles.html
 
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SpeedThrills said:
Thanks, Doc. I'll have to call them (and PST) for details.
They look the same, except Dr. Diff has no MC for A body w/ man brakes (mine), no control arms and ball joints, and no adjustable proportioning valve, unless the distribution valve is for that purpose. If that's the case, it won't work because my GM rear drums will require adjustable F-R bias.
The $435 goes up a bunch when I add the items PST includes.
PST has free shipping, Dr. Diff $293.00!
Click to expand...

I stock everything you listed, and much more. USA ground shipping is not $293.

Stage 1 brake kit $445
10.95" Front Disc Brake Kit (Stage 1)
Adjustable prop valve $35
Adjustable Proportioning Valve
A-body front suspension kit including assembled upper control arms $335
Mopar Suspension Rebuild Kit
Aluminum master cylinder package $95
Mopar Aluminum Master Cylinder Kit
TOTAL $910

Of course many options are also available such as Hemi booster assemblies, suspension hardware, drilled/slotted/plated rotors, stainless flex hoses, pre-bent brake lines etc...
 
sccachallenger said:
Mopar Action featured a brake swap years ago that used your knuckle. You'd use the 11.75" factory rotor and use a 4 piston caliper. Not sure if it was early Viper or wilwood. Andy F might have been the source for the caliper bracket. Might be worth looking into as it uses stock rotors.
Click to expand...

Yeah that is a blast from the past! I was messing around with disc brake conversions 20 years ago and that was one of the combinations I came up with. Somehow I figured out that the late model A body drum knuckle used the same exact spindle as the disc knuckle. A lot of people didn't believe me when I told them that including Eberg. But he quickly came around once he looked up the bearing cross reference info. Since a rotor slides right on it just took a little reverse engineering to develop a caliper bracket. I tried a few different calipers but eventually decided the early Viper caliper was the best (and coolest). It was a nice little conversion kit that worked pretty well but eventually Viper calipers got hard to find so I gave up on it. Cass redesigned it and made it better which is cool. I eventually upgraded my cars to 17 inch rims and 13 inch rotors but I still use Viper calipers.
 
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