Brakes Mark VII Brakes

Beau Granbois

Active Member
Oct 9, 2012
39
4
29
NE Montana
I have a '90 LX that I'm doing a brake swap and axle swap from a 91 Mark VII. I'm wondering if I could/can use the brake booster and master cylinder? I was looking at it the other day and the reservoir on the Mark VII is pretty big, compared to the stock mustang. I'm sure it will fit, I'm just wondering if theres any problems with using it. Thanks
 
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Check to see if it is a 2 or 3 line master.
I believe you will find it is a 2 line, but not sure.
They sell kits to convert your car to 2 lines.

Have you measured the rear?
It is like 2" wider with the Mark axles. (The housing is the same width, the axles stick out substantially more.)
I figure you have, but just checking incase you hadn't.
 
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No. Mark uses a sort of hydroboost setup. It's not compatible unless you want to drag the whole system over which involves running lines to the power steering

The 1991-1992 Mark 7 use a different type of rear brake. It was used only those two years, and on the 1993 Cobra R (contrary to popular belief, and Ford's own M2300-K instructions, the Cobra R did not get the same rear brakes as 94-98 Cobras) . It's a 10.5" vented rotor with a Varga caliper VERY similar to the Sn95 caliper. Unsure of the piston size, but checking rockauto.com shows it to be a 2.12" diameter piston (almost 54mm). If it is a 54mm rear caliper, you can use the same brake setup as a 84-86 SVO as they also use the same 73mm front brakes as the Mark 7 and a 54mm rear caliper

The SVO Mustang is similar to the mark 7 and uses a 1 1/8" bore MC. I beleive the MC on the Mark 7 is the same, but steel. It can be used, but use your current vacuum booster. The issue will be doing a 3-2 port conversion using an MC threaded in SAE on the car with metric lines. I beleive MM sells the adapter kit

http://www.maximummotorsports.com/store/index.php?main_page=index&cPath=49_140_517_520_539
 
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Thanks 5L5, what MC would you suggest I run? I've read that 94-98v6, 94-95gt, 94-95cobra, And 85 towncar can be used? What about a booster? Can I use the stock 4 cyl one thats on it or do I need to get a different one as well? Thanks for your help.
 
No. Mark uses a sort of hydroboost setup. It's not compatible unless you want to drag the whole system over which involves running lines to the power steering

The 1991-1992 Mark 7 use a different type of rear brake. It was used only those two years, and on the 1993 Cobra R (contrary to popular belief, and Ford's own M2300-K instructions, the Cobra R did not get the same rear brakes as 94-98 Cobras) . It's a 10.5" vented rotor with a Varga caliper VERY similar to the Sn95 caliper. Unsure of the piston size, but checking rockauto.com shows it to be a 2.12" diameter piston (almost 54mm). If it is a 54mm rear caliper, you can use the same brake setup as a 84-86 SVO as they also use the same 73mm front brakes as the Mark 7 and a 54mm rear caliper

The SVO Mustang is similar to the mark 7 and uses a 1 1/8" bore MC. I beleive the MC on the Mark 7 is the same, but steel. It can be used, but use your current vacuum booster. The issue will be doing a 3-2 port conversion using an MC threaded in SAE on the car with metric lines. I beleive MM sells the adapter kit

http://www.maximummotorsports.com/store/index.php?main_page=index&cPath=49_140_517_520_539
Thanks 5L5, what MC would you suggest I run? I've read that 94-98v6, 94-95gt, 94-95cobra, And 85 towncar can be used? What about a booster? Can I use the stock 4 cyl one thats on it or do I need to get a different one as well? Thanks for your help.
 
Which MC depends on your rear calipers. Can you measure the pistons? Are they 2.12" in diameter, or 1.7" in diameter??

The fronts are 73mm in diameter.

SO, if your rear calipers are 2.12", you want an 84-86 SVO MC with 1 1/8" bore (you might be able to use the mark 7 MC, but it's cast iron).

If your rear calipers are smaller..1.7", you'd want a slightly smaller MC like a 94-95 GT MC which is a 1 1/16" bore


Do you have pics of the rear brakes? I just want to verify they are the correct ones i'm talking about.
 
I'll see if I can get some on my lunch break. Will it be alright with the rims still on if i can get a good shot? I was planning on using the mark vii rear axle and I believe they are the stock brakes. The Mark is a LSC if that makes a difference?
 
No. Mark uses a sort of hydroboost setup. It's not compatible unless you want to drag the whole system over which involves running lines to the power steering

The 1991-1992 Mark 7 use a different type of rear brake. It was used only those two years, and on the 1993 Cobra R (contrary to popular belief, and Ford's own M2300-K instructions, the Cobra R did not get the same rear brakes as 94-98 Cobras) . It's a 10.5" vented rotor with a Varga caliper VERY similar to the Sn95 caliper. Unsure of the piston size, but checking rockauto.com shows it to be a 2.12" diameter piston (almost 54mm). If it is a 54mm rear caliper, you can use the same brake setup as a 84-86 SVO as they also use the same 73mm front brakes as the Mark 7 and a 54mm rear caliper

The SVO Mustang is similar to the mark 7 and uses a 1 1/8" bore MC. I beleive the MC on the Mark 7 is the same, but steel. It can be used, but use your current vacuum booster. The issue will be doing a 3-2 port conversion using an MC threaded in SAE on the car with metric lines. I beleive MM sells the adapter kit

http://www.maximummotorsports.com/store/index.php?main_page=index&cPath=49_140_517_520_539

Also need to consider that maintenance parts for those rear brakes are harder to find and expensive... rotors, calipers, etc... and won't get anymore common as time goes on.

I was going to bring these things up, but the OP was pretty short in his first post and seemed to know what he was getting into.

As for the brackets, you can buy some from the link provided, or you can google the "bracket flip" to mod your existing brackets to work with Fox axles.
 
I'll see if I can get some on my lunch break. Will it be alright with the rims still on if i can get a good shot? I was planning on using the mark vii rear axle and I believe they are the stock brakes. The Mark is a LSC if that makes a difference?

yeah just sneak a shot of the caliper between the spokes or from the backside of the rim where the tailpipes are. You are using the entire axle as is?

You might run into an issue with the e-brake. It's been some time since i've been under a Mark 7, but i think the way the brake is mounted is different. I think the mark 7 uses a floor pedal to set the brake? The only Mustangs to receive those brakes from the factory were the 107 Cobra R's and a handful of 92-93 Saleens. It might make an e-brake solution kinda tricky.

These brakes are very clost to 94-98 GT brakes, but i don't know if they share the SN95 offset or the mark 7's super-increased offset
 
Thanks for all of the info guys. I do kind of know what I'm getting myself into. I came across a kit that will fix the e-brake situation. I'm using the mark vii parts because thats the donor car that I have. I talked w another member and the subject of the availablity of parts for the mark vii. I willing end up swapping them out if it comes to being to expensive for replacements. I want the mark rear axle because its the 8.8, has the discs and has trac loc. Also because I live in rural Montana and parts are very hard to find around here for any mustang. I actually just came across this mark by chance and the guy only wanted $500 for it. Running, title, SC Cobra top 5.0. The PO thought the trans was out in it and it turned out the B&M shifter was jammed up, so it drives now too. My first car was a fox mustang and I always wanted to get another. Recently picked up the 90 lx vert, so I was just gona swap everything that I could and get it running and deal with the other stuff when I have the time and money to.
 
Ok, I was able to get a shot of the brakes. Here they are.
IMAG0535.jpg
IMAG0536.jpg
IMAG0537.jpg
 
They look like. Sn95 brakes

They do. They are very similar, but slight differences. I'm not sure of the piston size though. But it's a 10.5" vented rotor vs the solid rotor found on the 94+ GT/v6

The e-brake looks VERY similar to SN95 e-brake. In fact, it looks pretty much identical. I bet you could just run the same cables as you would with an Sn95 brake conversion and be fine.

Rotors, calipers and pads are available for those brakes. I wouldn't sweat not being able to find parts in the future.