Brake Upgrade

[2point3fiend]

I need some help with a brake upgrade I'm wanting to do on my 93 Mustang 5.0L. I've decided to go with the Lincoln Mk 7 73mm front calipers, retaining my stock 4-lug rotors and stock drums in the rear. My question is, if I just want to go to the 73mm calipers, do I need to upgrade my brake booster and master cylinder or just the MC itself or either of those at all? I've been told that the stock brake booster, with the 93 Cobra MC, using the Mk7 calipers will be sufficent. I wanted a few second opinions though. Can anyone help with my problem? I've found lots of options scouring the internet, but no real tested and tried information about how I want to go about my setup idea.

 

[bcd]

I dont know but the answer is probably here
http://mjbobbitt.home.comcast.net/mustang/5lug.html

 

[90lxcoupe]

i just ordered what i think is the same setup from MM and with myne i ordered the SVO master cylinder, i havent seen anyone chane out the booster itself, and also i was told by MM that its not a good idea to use drums wiht the upgraded master cylinder.

 

[tunedin302]

Your stock booster and MC will be fine if going with only the 73mm calipers and keeping the drums. The cobra is a 2 port MC and you currently have a 3 port MC ... no biggie when you go to a rear disc since you can do a conversion or swap in a new 2 port MC. Check out this link for further info and click on "1979-1993 4 - lug"

http://sn95brakes.cjb.net/

 

[93-331-29psi]

I am running the 13 inch cobra braks on my 86 and I have no problems at all using the stock master cyl. Since you are staying drum in the rear I'd let it go.

 

[srothfuss]

Edit: I was beaten to it

Try just swapping out the calipers and go from there. Are you going to add SS lines also? What about some cermaic pads?

 

[93-331-29psi]

Edit: I was beaten to it

Try just swapping out the calipers and go from there. Are you going to add SS lines also? What about some cermaic pads?

Good point, I would invest in the stainless braided brake lines. They will help take and sponge feeling out of the brake pedal feel.

 

[2point3fiend]

I plan on using the kevlar virtual dustless brakepads. They are green in color, forgot the brand off-hand. Got them from 50resto.com. I plan on buying some Bendix slotted rotors too to go along with it. I do indeed intend on buying the complete stainless steel brakeline kit from somplace. Don't know where exactly to aquire such a thing, any suggestions?

 

[srothfuss]

MM, Steeda (?) and I believe 5.0resto sells one of them.

The green pads you got are from HAWK. Good stuff from what I hear.

 

[2point3fiend]

By the way how much brake fluid is in a 1993 mustang 5.0's system?

 

[5.0fox]

im interested.... just subscribing

 

[8950HO]

There is a problem adding 73mm calipers with the stock rear drums.

The problem is the rear wheel cylinders are too small,(3/4" bore),to work properly with the larger 73mm calipers and need to be upgraded to a larger size to maintain proper balance in the system.

1988 T-Birds with 9" drums used a 1" bore wheel cylinder that 3 sources have told me will fit the 9" Mustang drums.This size should roughly maintain the proper balance with the 73mm calipers.

Search on the Corral for a thread called..."actual stopping distance improvement with 73mm calipers".
The tech guy from Maximum Motorsports talks about this rear wheel cylinder issue in there.
It`s a long thread though.

 

[2point3fiend]

Hey 8950HO, so I can buy a new pair of stock Mustang drums and then I have to buy the 1" T-bird rear wheel cylinder seperately? How difficult is that to add to the rear drum brakes?

 

[tunedin302]

By the way how much brake fluid is in a 1993 mustang 5.0's system?

About (3) bottles.

 

[Shakerhood]

There is a problem adding 73mm calipers with the stock rear drums.

The problem is the rear wheel cylinders are too small,(3/4" bore),to work properly with the larger 73mm calipers and need to be upgraded to a larger size to maintain proper balance in the system.

1988 T-Birds with 9" drums used a 1" bore wheel cylinder that 3 sources have told me will fit the 9" Mustang drums.This size should roughly maintain the proper balance with the 73mm calipers.

Search on the Corral for a thread called..."actual stopping distance improvement with 73mm calipers".
The tech guy from Maximum Motorsports talks about this rear wheel cylinder issue in there.
It`s a long thread though.

I was going to bring this very point up that it is not a brake upgrade, but a brake Downgrade as was in the Tech Article on the Corral!

 

[8950HO]

I was going to bring this very point up that it is not a brake upgrade, but a brake Downgrade as was in the Tech Article on the Corral!

Yeah,it gets confusing.The downgrade part is using the stock wheel cylinders with the 73mm calipers.

However nobody has said,and I don`t know how much of an improvement there would be with 73mm calipers + the 1" bore wheel cylinders to correct the imbalance compared to 73mm calipers and stock 3/4" wheel cylinders.

I believe the MM guy said a 5.0L stang they tested with 73mm calipers and the stock drums and 3/4" wheel cylinders took 15ft longer to stop from 60mph,compared to the 60mm calipers.But they didn`t try larger wheel cylinders,so I have no idea how the car would stop had they also done a test with the bigger wheel cylinders..

As it stands nobody really knows how much better, (if any) a 5.0L stang would stop with;
60mm calipers + stock 3/4" wheel cylinders versus 73mm calipers + 1" wheel cylinders.

 

[cardudeusa]

I have a 90 GT and my wife has an 87 GT, and both have the 73MM upgrade. I have no numbers to back it up, but both of them had significant gains in stopping. I used the EBC green pads on my 90 and love them, also reccomend ss lines like mentioned, and the ss caliper sleeves. On my 90 I have the stock M/C and on the 87 I have the 2 port older style. I reccomend the 2 port as the 87 has a better pedal feel. Just my .02.

 

[Shakerhood]

I have a 90 GT and my wife has an 87 GT, and both have the 73MM upgrade. I have no numbers to back it up, but both of them had significant gains in stopping. I used the EBC green pads on my 90 and love them, also reccomend ss lines like mentioned, and the ss caliper sleeves. On my 90 I have the stock M/C and on the 87 I have the 2 port older style. I reccomend the 2 port as the 87 has a better pedal feel. Just my .02.

If I remember reading the Thread correct, the fronts will lock up way early compared to stock and you lose out on any threshold braking thus increasing stopping distance.

 

[OL' WHITEY]

MM, Steeda (?) and I believe 5.0resto sells one of them.

The green pads you got are from HAWK. Good stuff from what I hear.

The green pads are made by EBC. They're called EBC Green stuff pads. Hawks are not green, they're black. Both Hawk and EBC are excellent pads. Sorry to nitpick here.

Dave

 

[cardudeusa]

If I remember reading the Thread correct, the fronts will lock up way early compared to stock and you lose out on any threshold braking thus increasing stopping distance.

I've never had the fronts lock up, it may be because I have large front tires?