Power Brakes ina 68 with JMC hydraulic clutch

[jcode68]

Well, I spent a lot of time on this forum, calling vendors and researching various options for installing power brakes in my 68 Fastback. I hit many walls since I am running the JMC hydraulic clutch kit. There were many people on this forum who were very helpful during my research, but at the end of the day there wasn't one Stangnetter with a 67/68 power disc brakes running the JMC clutch that could provide absolute information. Since I took the plunge and worked through this install, I decided to write it up and provide an official post that will hopefully help others considering this swap. I'll apologize in advance since this is a long one with many pics. The write up is also part of my Cardomain pages and references other project work I have done.
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Okay, now that I have power to spare, I needed a serious upgrade to the 38 year old manual 4 wheel drum brake system from Ford. I had a few requirements when shopping for a performance front brake system: <?***:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o></o>
1)Wanted to retain my 15" Torque Thrust wheels
2)Wanted to upgrade to power assist brakes
3)Wanted a high performing and good looking setup that wouldn't rust over the first time it got wet.
4)Perhaps most important, needed to be compatible with my JMC Hydraulic Clutch install. <o></o>
I spent a lot of time comparison shopping the big 3 - Baer Brakes, WilWood and Stainless Steel Brake Company (SSBC). I decided to go with SSBC based on quality, reputation, price, completeness of their kit and I could use my 15" wheels. (important to point out, none of the brake companies offer a power booster setup that is compatible with the JMC Hydraulic Clutch kit. More on this below) <o></o>
I ended up going with their Force 10 kit and upgraded the 4 piston calipers to include the red powder coat finish. The rotors are slotted and plated with their "Xtra Life" plating to protect against rust. The kit I got was for manual front disc brakes and did not include a power booster. As I stated above, my research determined that the only power booster that would co-exist with my JMC Hydraulic Cutch kit on a 67/68 Mustang was the OEM booster made by Bendix. I was able to locate a brand new Bendix booster, matching master cylinder and brake pedal (yes you need a new pedal as well) from a guy who had planned the exact same swap in his 68. He changed his mind and decided to go with a hydroboost setup and let these parts go for a good price. Ok, now I have all the parts, let's go through the install: <o></o>
Installation of the SSBC kit was pretty straight forward. I started by removing the original front drums as a complete unit, leaving just the original spindles, which were in great condition. Here's a pic of the new dust shield and caliper mounting bracket installed: <o></o>

The kit includes everything you need including inner & outer bearings, grease seal and attaching hardware. Just needed to pack the bearings with fresh grease and put them on the original spindles and follow the bearing tourque procedure:

 

[jcode68]

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Next was to install the brake pads (included) into the calipers and then bolt them to the bracket. This part of the install was a breeze. Most of the work was installing the power booster and the replumbing involved.

On to the Master Cylinder
This is the best picture I have to show what I started with - see the crusty non-power master cylinder in the corner?:

Upgrading to power brakes is pretty involved as you will see. It involves changing out the brake pedal assembly for the correct length pedal, which requires removal of the pedal assembly up behind the dash, which requires removal of the steering column... Here is are a couple of shots with everything removed:

You can get a good shot at the JMC Hydraulic Clutch master cylinder in these shots. It's gonna be tight!
Here's a shot of the pedal support assembly on the bench.

 

[jcode68]

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Adding the Bendix booster requires slight fabrication to the pedal support. There are 3 threaded fittings that need to be removed - see photo:

Just needed to grind the welds on the other side and punch them out to expose the holes. Here's a shot of the finished product:

This shot shows the difference between brake pedals - the power brake pedal is the longer one:

Was pretty straight forward to swap the pedals. I also checked and greased all the bushings on the clutch pedal while it was on the bench.

Here's a couple pictures of the Bendix booster:

And new master cylinder:

 

[jcode68]

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You will also need to increase the opening of the hole in the firewall about a 1/2" on top to accomodate the new booster. I used a small hack saw and made several straight cuts and then used vice grips to bend the metal until it broke. I was pleased with how clean the hole was when I was finished:

Here's a shot with the booster mocked in place. Notice how tight it is to the JMC clutch cylinder - BUT IT FITS!

I mocked up the booster and master cylinder and bent up new lines from MC to distribution block (I decided to keep the original distribution block as it was in perfect condition). Also needed to install and plumb a proportioning valve for the rear brakes since a 4 wheel drum brake system does not have one. You can see it in the pic below:

Back on the inside, here is an under dash shot with everything removed and brake hole enlarged:

I put the pedal support back into place next, here are a couple of shots:

 

[jcode68]

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Here's a pretty good underdash shot showing the new booster rod assembly and brake switch mounted to the pedal:

Back up top, I got the booster and master cylinder mounted for the last time. The second picture shows just how close it comes to the shock tower - got about 3/4" there:

Here's a final shot of the plumbing with the master cylinder installed. It's a very tight fit, but everything is in there.

The steering column is back in and everything is complete. I now need to bleed the system, hookup the vacuum hose and go for a test drive. I'll post another update probably this weekend with performance information.

 

[180 Out]

Great post(s)!

One thing you might want to check before you get everything buttoned up and bled is firewall flex when you step on the brakes. Have someone apply the brake pedal while you watch from under the hood. If you see the MC/booster moving too much you might want to consider getting a reinforcement plate from Modern Driveline. However much firewall you get is going to be pedal motion that's not translating into hydraulic line pressure; the result is a squishy pedal.

 

[jcode68]

Great post(s)!

One thing you might want to check before you get everything buttoned up and bled is firewall flex when you step on the brakes. Have someone apply the brake pedal while you watch from under the hood. If you see the MC/booster moving too much you might want to consider getting a reinforcement plate from Modern Driveline. However much firewall you get is going to be pedal motion that's not translating into hydraulic line pressure; the result is a squishy pedal.

Thanks for the tip, I will check into this. The firewall seems pretty firm, especially with the heavy guage steel pedal support on the inside giving more support. I hope it's not an issue since I really don't want to have to pull this apart again

 

[dawtips]

Nice write-up.