Disc brake upgrade

[Ohio Ken]

Hey guys
My '92 CR cobra has 8" front disc brakes and rear drums, and non booster assist master cylinder. She goes fine but slows and stops like crap.
I am looking to upgrade at least the front this winter.
Being a '92 I am a little concerned about high dollar upgrades such as Baer or Wilwood .

I can find 11" single piston brakes for around $500.00-$700.00, vs 4 piston at $1100.00-$2000.00, I assume I would order for a '74-'78 MustangII? Also would like to add power assist master cylinder.
Any thought or recommendations? And to confirm, I would buy for mustangII right?
Thanks
Ken

[Wisconsin_Snake]

A quick search for mustang ii brake upgrades resulted in this kit
WEB SPECIAL $335 Mustang II Hi Tech 2 Piece Disc Brake Kit
Seems like it's just about everything you need for under $400. I would like to see a review on the kit.

[Wisconsin_Snake]

Here is another
Engineered Components, Inc. - Your One Stop Brake Shop!
I have first hand experience with their front disk conversion for a 1957 Chevy, it was top notch and much better than the other set ups is tried.
They mention that the mustang ii kit does not move the wheels out. A very important fact.

[saltshaker]

You can get a 11" kit with GM single piston calipars for aroung $300
Jon

[RallySnake]

I have just upgraded to Wilwood 6 piston calipers and 11 " rotors and they have been very impressive on the track.

[MaSnaka]

I replaced the 9" Pinto discs on my CR with the Wilwood 11" 4 piston Dynolites. I think I dropped about 20lbs per wheel, number is a little fuzzy but it was significant. I also changed the pedal ratio which made a huge difference. There are pictures in my gallery of the mods to the brake pedal. Stopping improved greatly. Later I replaced the rear drums with 11" Wilwoods, new master and proportioning valve. I didn't notice a big change in stopping ability but I am glad for the upgrade.

John

[Ohio Ken]

Originally Posted by MaSnaka

I replaced the 9" Pinto discs on my CR with the Wilwood 11" 4 piston Dynolites. I think I dropped about 20lbs per wheel, number is a little fuzzy but it was significant. I also changed the pedal ratio which made a huge difference. There are pictures in my gallery of the mods to the brake pedal. Stopping improved greatly. Later I replaced the rear drums with 11" Wilwoods, new master and proportioning valve. I didn't notice a big change in stopping ability but I am glad for the upgrade.

John

Thanks John,
When you say you did not notice much improved stopping, are you referring to just the new master cylinder and proportioning valve? Because I would think Wilwood 11" on front and back would be a tremendous improvement.

[cycleguy55]

As we all know, the front brakes do most of the work, so it's easy to see why MaSnaka didn't see that much difference when replacing the rear drums with Wilwoods. I don't know about his CR, but my West Coast has 11" drums from a 1978 Thunderbird, and most of the other donor cars are probably in the same size and weight class. For a '78 T-Bird the drum brakes helping stop a car that weighed ~4200 lbs., quite a bit more than my WC Cobra, so they're pretty good stoppers already, though clearly not up to track duty mostly because of their lower ability to shed heat.

[Ohio Ken]

Yeah, I misread his post the rear upgrade and master not as noticeable. Front definitely the biggest impact.
Being these cars are so lite , I wonder about the advantage of 4 piston front disks vs cheaper single piston. This is probably my biggest dilemma at this point?

[cycleguy55]

Originally Posted by Ohio Ken

Yeah, I misread his post the rear upgrade and master not as noticeable. Front definitely the biggest impact.
Being these cars are so lite , I wonder about the advantage of 4 piston front disks vs cheaper single piston. This is probably my biggest dilemma at this point?

Ditto - I've been fussing with ~$400 for drilled and slotted 11" single piston kit, or double that (or more) for 4 piston SSBC, Wilwood, etc. My car is strictly a street cruiser, though I suppose at some point I may try a bit of autocrossing. The 9.25" Mustang II discs on the front of my car seem to do a decent job already, and my take is 11" drilled and slotted rotors with the large GM calipers will be a significant upgrade.

If I was planning on real track use I'd likely go multi-piston, but that's not likely as we have no local track, and none being planned (that I know of). OTOH, it's always nice to look through the wheels and see those red calipers, and they'd likely help a bit when it comes time to sell it.

[Wisconsin_Snake]

When getting the kit, be aware if it moves your wheels out or not..

Also, can someone chime in if the existing mustang booster/master will work fine with the larger calipers?

Otherwise going the Wilwood route may not be that bad IF you can retain the existing master/booster.

[Double Venom]

Masnaka,

Depending on your MC, although I've done both ways with little or no known problems. How ever if you are using the Corvette 7" Booster (actually made for 4 way discs) really works well.

Slotted and Drilled: Baer and Wilwood both advised us to never use "Drilled" rotors as each hole acts as a heat sink and can, (and will crack like a heated marble dropped into water ) Two road courses and I had to junk a brand new set of rotors.

[Rick Parker]

The single piston GM Calipers will make a significant improvement over the much smaller Mistang II Brake package although the calipers themselves are faily heavy. I used Calipers from a Nova which are similar to that of a Camaro except for how the brake hose attaches. You can also upgrade to different pads for another major improvement. Unless you are doing open track often, the 11" rotors and GM Calipers provide quite adequite stopping power, they aren't as nice to look at as a set of Brembo, Baer or Wilwoods, but the expense is much less too. Combine them with Mustang Cobra or TBird Turbo Cpe rear brakes and it makes a very good inexpensive package. Ive been using this combo for several years with no regrets . Pictures are in my gallery,

[Ohio Ken]

Originally Posted by Rick Parker

The single piston GM Calipers will make a significant improvement over the much smaller Mistang II Brake package although the calipers themselves are faily heavy. I used Calipers from a Nova which are similar to that of a Camaro except for how the brake hose attaches. You can also upgrade to different pads for another major improvement. Unless you are doing open track often, the 11" rotors and GM Calipers provide quite adequite stopping power, they aren't as nice to look at as a set of Brembo, Baer or Wilwoods, but the expense is much less too. Combine them with Mustang Cobra or TBird Turbo Cpe rear brakes and it makes a very good inexpensive package. Ive been using this combo for several years with no regrets . Pictures are in my gallery,

Leaning this way, just a cruiser and sometimes wind her out. BTW, Is the brake fluid DOT 3?
Would love to go with the high end stuff, but at the end of the day, my '92 is only worth around $28,000 , I paid that this year then already put a couple grand in it. Guess it will come down to if there is a decent Christmas bonus this year lol.

[Ohio Ken]

Originally Posted by Wisconsin_Snake

When getting the kit, be aware if it moves your wheels out or not..

Also, can someone chime in if the existing mustang booster/master will work fine with the larger calipers?

Otherwise going the Wilwood route may not be that bad IF you can retain the existing master/booster.

John,
I will definitely watch for the right kit to avoid offset issue. The peddle angle you spoke of earlier... Is the longer one in your photos for non booster assist? I would like to swap out MC for one with a power booster.... Would a say 1994 mustang master with booster work?

[Double Venom]

O.K.

The best I have found for moderate boosting power is the 7" 84 +/- Corvette booster. Straight swap, and is made for 4 whl discs. Not only does it work great but the smaller size is a big plus.

[cycleguy55]

Originally Posted by Rick Parker

The single piston GM Calipers will make a significant improvement over the much smaller Mistang II Brake package although the calipers themselves are faily heavy. I used Calipers from a Nova which are similar to that of a Camaro except for how the brake hose attaches. You can also upgrade to different pads for another major improvement. Unless you are doing open track often, the 11" rotors and GM Calipers provide quite adequite stopping power, they aren't as nice to look at as a set of Brembo, Baer or Wilwoods, but the expense is much less too. Combine them with Mustang Cobra or TBird Turbo Cpe rear brakes and it makes a very good inexpensive package. Ive been using this combo for several years with no regrets . Pictures are in my gallery,

Certainly the pad and rotor sizes are larger in the various 'big brake' kits, and I'm thinking more pad and a larger rotor diameter should provide more braking power. The kits I've been looking at have a 70mm piston, but I'm curious about how much larger those are than what I currently have. Any idea what size the pistons are in a Mustang II or Pinto caliper?

My rear axle is 9" Ford (large bearing, so-called 'late style' or 'Torino' ends), not 8.8", so the Cobra or Turbo Coupe brakes won't work. I note many of the 'big brake' kits using GM calipers are also available for this, but I may do that as a later upgrade (fronts now, rears later), or maybe I should just leap in and do it all at once. Perhaps if I'm swapping out the fronts and bleeding the brakes I may as well do it all at once.

The reservoirs attached to the brake and clutch master cylinders on West Coast Cobras can only be accessed through the wheel well, which makes checking and adding brake fluid a PITA. I have a couple of reservoirs I'm going to install at the same time as remote reservoirs to address this issue. I only need to figure out a good spot to locate them and get appropriate tubing / hoses to connect them to the master cylinders.

The plan is also to reverse bleed the whole system, discharging the old fluid through the remote reservoir hoses before connecting them to the reservoirs which I'll then fill with fresh fluid.

Thoughts?

[Rick Parker]

The 11" Granada rotors will move your wheels out about 3/4" on each side + 3/8" if you use knock off adapters, this does not consider any difference in wheel offset.

[cycleguy55]

Originally Posted by Rick Parker

The 11" Granada rotors will move your wheels out about 3/4" on each side + 3/8" if you use knock off adapters, this does not consider any difference in wheel offset.

I have a found a few kits which state they move the wheels out 0.25" or, in some cases, none at all. My objective is to keep my wheels where they are, if at all possible.

[MaSnaka]

Keep in mind if you are changing to a rear disc set up you will need to change the MC with the larger rear brake reservoir. So if you plan to do the rear brake upgrade later it will pay to plan ahead if replacing your MC first.

Ohio Ken,
Originally my car had the 9" Pinto brakes, no booster. The original pedal ratio was meant to be used with a booster. The longer brake pedal in my gallery photo is the one meant to be used with the booster. The existing pedal box has the holes drilled to use a different pivot point, but I had to modify my pedal to fit. Keeping the MC piston rod in the same location I shortened the pedal arm and relocated the pivot point which gives much more foot leverage to the pedal when applying the brakes. Cost about $20. With no booster added this change alone made a world of difference. Upgrading the fronts to the 11" Wilwoods made another huge difference. I just didn't notice such a difference with the rear brake upgrade. Right now the car stops righteously. I have no plans to make further upgrades. BTW- I am using DOT3 with a 15/16" MC. To quote someone else I saw on the forum "the better I can stop, the faster I'm willing to go". True that.

Also if working on your pedal box area, hint: take off your steering wheel. Makes accessing the narrow space a lot easier.

John