front 13" brake Caliper options

RichV

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When rules were changed for my race class, and we were allowed 13" front rotors with 4 pison calipers I did some research to see what is the most economical upgrade, along with brake pad prices for my use. Some of you guys were interested in seeing the options so I'll spec out each with the pros and cons, IMO of course.

Brembo Cobra R setup

Can be bought for $1300ish. This includes calipers and rotors. For my application I need blank rotors (per rules), so I would have to puchase another $150+ of rotors, then a set of pads.
M2300X.jpg

Pros:
decent intial cost
bolt directly to SN spindle, no adaptor or modification

Cons:
added cost of pads (and rotors for my use)
calipers are not available seperately, not that I could find
still need braided brake lines at added cost (I did not have these)

Wilwood Calipers

Couple of options here. Neither are 'Willwood' per say, as far as kits. Most of these styl kits use off the shelf calipers with some sort of adapter brackets to the spindles. I found a couple of options, one was a kit from revolutionbrake.com, and one was a set of brackets from cmcparts.com. The kit was the obvious choice.

revolutionbrake.com sells the complete kit with: rotors, calipers, pads, braided lines, hardware, and brackets for about $1150. No brainer for bang-for the buck. They have kits for 13" Cobra and 11" GT/V6. But you may as well pop for the 13" setup, price is the same.
DSC05213.JPG


They also sell just the brackets for the Wilwood calipers for $299. This is good if you want custom piston sizes or just different calipers from the ones included in the kit. I just went with the 120-11132 Bridgebolt calipers in the kit.

Pros:
calipers can be bought anywhere in the $150/ea range if one dies
kit is complete, everything necessary to get you running
bridgebolt calipers take about 5 minutes to change pads, no caliper removal necessary at the track
pads are CHEAP, $80ish for Wilwood black pads (these are low/med temp roundy racer pads that work well for open track) street pads are cheaper, look for Wilwood or HAWKs under $100/set
pads are a .800 thickness which is a lot of meat (last you long time) *must say it in 'love you long time' voice :)

Cons:
spindle modifications, specialy for 94/95 cars. yep ... keep grindin'.

The cmcparts.com may not be an option anymore. They were on the fence whether to make any more brackets,but cost was $280 for the set with hardware. Then you had to get the same or similar calipers with the revolution kit, plus lines, rotors, and pads. Not a bad option, these brackets did relocate your calipers a little, and did not require any spindle modification. That was a plus, but I've never seen them on a car. There was talk of the calipers keeping in production, but I'm not sure what hapened to it.

Other options from StopTech, BAER, BrakeMan.com, and Alcon were available, but very high priced (compared), pads were expensive, and replacement parts were hit/miss. Most kits were $2000+ and were just not in the budget or me. My car is all function, so I'm not concerned with color or look of something, so price, serviceability, and performance are major players in my choice.

Rear brakes have some good options out there as well, however the Cobra/GT Varga caliper with some good pads and the 11.65" vented Cobra rotors is all you really need. Revolution also has a rear kits for around $1000, with some Wilwoods, same setup as their fronts. That would be the ultimate track setup.

Lots of other options out there, even larger rotors.
 

Slykin

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All I know is I at least need better pads... The fade after 5-10min of running on my first track day was terrifying. Almost completely lost my brakes at the end of a 100mph straight :mad: Would you consider the Cobra brakes sufficient for a few 20-25min. sessions on a hilly track as long as I got better pads? Thanks!
 

Magic

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Good write up!

There was a time, back in 08, maybe it was 07, the M-2300-X kit (the 4 piston Cobra R Brembos) could have been had for $5-600 for the complete kit. However, the odd pair of Brembo calipers do show up for sale, but usually for $4-600 for just the calipers and nothing else.
 

Magic

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All I know is I at least need better pads... The fade after 5-10min of running on my first track day was terrifying. Almost completely lost my brakes at the end of a 100mph straight :mad: Would you consider the Cobra brakes sufficient for a few 20-25min. sessions on a hilly track as long as I got better pads? Thanks!

Whats your current pad and rotor combo?
 
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RichV

RichV

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All I know is I at least need better pads... The fade after 5-10min of running on my first track day was terrifying. Almost completely lost my brakes at the end of a 100mph straight :mad: Would you consider the Cobra brakes sufficient for a few 20-25min. sessions on a hilly track as long as I got better pads? Thanks!

Plenty of brake. I've been running 3 seasons on 11" GT brakes. Granted my race car weighs around 3150 pounds with driver, but even with interior you may be 100 lbs or so heavier. I'm running r-compound tires which will help stop the car much more agressive, but heat the brakes faster. Street tires aren't as hard on the brakes, but you're riding the brakes a little longer making more heat.

There's a few different scenarios if you're loosing brakes.
-small rotor that can't dissipate the heat, or you need brake cooling
-pads are out of heat range to be effective, if you put too much heat in street pads it will feel like fade
-boiling the fluid
-balance issue, not enough rear bias

I'd start with figuring out which problem you have, or fix all of them. The pads are the obvious choice, I know track pads very well. Do research on a good medium temp pad, med-high temp pads do an awesome job on track, but you can't heat them up enough for street driving and they'll crumble. Opposite is true for AutoZone or any part store pads, a few track sessions get them too hot and they come appart. I would look at HAWK, Carbotech, or EBC. Probably 1 step up from the street pads they offer. Brake fluid is important, it MUST be flushed regularly. I do it every 2 weekends, so that's roughly 5 hours of driving. I use a DOT3/4 synthetic, off the shelf stuff. Fancy DOT5 or better fluids would be good to try, but I'm gunshy because 5 does not mix with 3/4, it creates some funky acid that can eat brake parts/seals. So the 3/4 system needs to be fully evacuated before going to DOT5. The balance should not be an issue if you have OEM stuff. If you have a frankenstein of parts, like I do, it may be an issue where you need to add a rear bias adjustment, and adjust it at the track. Remove stock proportioning valve, you want to run it hard, brake hard, keep giving more to the rears until lock up. Then back off a couple of turns.

For brake cooling there are loads of options. You can get 3" cooler ducts from Jegs/ebay etc. You'll need maybe 4' per side, if you have a Cobra bumper without fogs, use those fog holes. I use the GT fog light holes, a little ghetto, but works. The key is to aim the air in the center of the rotor hat. Spindle air duct mounts are out there for our cars, you can do something in a Mustang kit from agent47, or something universal from speedwaymotors.

Agent47, about $250 with ducts
agent_47_sn95_brakecooling_kit.gif


All Star universal, $25-35 each, will need 2, plus the duct will be $50 or so
41lC4kgdjvL._SL500_AA300_.jpg
 
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RichV

RichV

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Good write up!

There was a time, back in 08, maybe it was 07, the M-2300-X kit (the 4 piston Cobra R Brembos) could have been had for $5-600 for the complete kit. However, the odd pair of Brembo calipers do show up for sale, but usually for $4-600 for just the calipers and nothing else.

Thanks! Yea, I remember that as well. I had a local guy selling a pair of calipers for $400, and it was attractive because there is no spindle modification. But once I researched spare parts for them, I knew they were not for me. Not for what I put the parts through.
 
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RichV

RichV

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thanks for this rich..you da man.....sub'd for when i convert mine

n/p!

Well, don't be gettin' lazy. I'll be out your way at the end of May, make sure you have all that stuff if you want to have a chance. :)
 

Slykin

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Plenty of brake. I've been running 3 seasons on 11" GT brakes. Granted my race car weighs around 3150 pounds with driver, but even with interior you may be 100 lbs or so heavier. I'm running r-compound tires which will help stop the car much more agressive, but heat the brakes faster. Street tires aren't as hard on the brakes, but you're riding the brakes a little longer making more heat.

There's a few different scenarios if you're loosing brakes.
-small rotor that can't dissipate the heat, or you need brake cooling
-pads are out of heat range to be effective, if you put too much heat in street pads it will feel like fade
-boiling the fluid
-balance issue, not enough rear bias

I'd start with figuring out which problem you have, or fix all of them. The pads are the obvious choice, I know track pads very well. Do research on a good medium temp pad, med-high temp pads do an awesome job on track, but you can't heat them up enough for street driving and they'll crumble. Opposite is true for AutoZone or any part store pads, a few track sessions get them too hot and they come appart. I would look at HAWK, Carbotech, or EBC. Probably 1 step up from the street pads they offer. Brake fluid is important, it MUST be flushed regularly. I do it every 2 weekends, so that's roughly 5 hours of driving. I use a DOT3/4 synthetic, off the shelf stuff. Fancy DOT5 or better fluids would be good to try, but I'm gunshy because 5 does not mix with 3/4, it creates some funky acid that can eat brake parts/seals. So the 3/4 system needs to be fully evacuated before going to DOT5. The balance should not be an issue if you have OEM stuff. If you have a frankenstein of parts, like I do, it may be an issue where you need to add a rear bias adjustment, and adjust it at the track. Remove stock proportioning valve, you want to run it hard, brake hard, keep giving more to the rears until lock up. Then back off a couple of turns.

For brake cooling there are loads of options. You can get 3" cooler ducts from Jegs/ebay etc. You'll need maybe 4' per side, if you have a Cobra bumper without fogs, use those fog holes. I use the GT fog light holes, a little ghetto, but works. The key is to aim the air in the center of the rotor hat. Spindle air duct mounts are out there for our cars, you can do something in a Mustang kit from agent47, or something universal from speedwaymotors.

Agent47, about $250 with ducts
agent_47_sn95_brakecooling_kit.gif


All Star universal, $25-35 each, will need 2, plus the duct will be $50 or so
41lC4kgdjvL._SL500_AA300_.jpg

I believe that at least the pads were no good.. they are the "high end" brand from Advance Auto or O'Reilly's and they turned my wheels BLACK after 3 20-25min sessions. I just figured they wouldn't go that quickly. Also, on the third session I got vibration at the steering wheel under braking. This went away after cooling down on the way home.

As far as fluid goes, I was running pretty fresh DOT3.. Granted, I think it might have been boiling, because my E-brake light came on and stayed on after my second session. I believe this is usually due to low fluid, but i'm assuming if it was boiling, it would do the same.

My brake set-up right now is Cobra fronts, with GT rears on a stock 94 GT MC. I'd like to get the Cobra MC sometime soon, should help out for several reasons. Does the cobra rear setup really help out much? I'm not even sure what the difference between the GT and Cobra rears are.

Thanks for all the info so far though! I've been thinking of fabbing up some ducting from my GT fogs, but haven't decided yet.
 
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RichV

RichV

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The Cobra rears are a little bigger, but they are vented. The GT rears are the same caliper. Not sure of the difference, I went straight for the 4 wheel upgrade at once. I just did the Cobra MC, so I'll report on the difference. The GT MC had zero feeling with the fronts, the pedal felt fine it just kept going to the floor with the same effort, then you lock up. I need the brakes to have a little more feel so I have a clue when lockup is coming.

Your part store pad story reminds me of my E30 BMW. I learned and got my comp license with the E30. Anyway, when I started open tracking it I went to NAPA and got a set of their premium pads with lifetime. When I started driving, the pads would last 3-4 weekends, then I'd exchange them. Well, I got faster, started really pushing the E30 after ST swaybars, H&R Race springs, and Billstein Sports, and add some RA1 tires. So now my pads were lasting 1 weekend. And the counter guys were on to my little scam, specialy when I brought in 2 backing plates that look like they were warped by heat, brake pistons embedded in the steel, and what was left of the meat was a dust that looked like cigarette ashes. Time for some decent pads. :)
 

BigBore96

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The Cobra rears are a little bigger, but they are vented. The GT rears are the same caliper. Not sure of the difference, I went straight for the 4 wheel upgrade at once. I just did the Cobra MC, so I'll report on the difference. The GT MC had zero feeling with the fronts, the pedal felt fine it just kept going to the floor with the same effort, then you lock up. I need the brakes to have a little more feel so I have a clue when lockup is coming.

Your part store pad story reminds me of my E30 BMW. I learned and got my comp license with the E30. Anyway, when I started open tracking it I went to NAPA and got a set of their premium pads with lifetime. When I started driving, the pads would last 3-4 weekends, then I'd exchange them. Well, I got faster, started really pushing the E30 after ST swaybars, H&R Race springs, and Billstein Sports, and add some RA1 tires. So now my pads were lasting 1 weekend. And the counter guys were on to my little scam, specialy when I brought in 2 backing plates that look like they were warped by heat, brake pistons embedded in the steel, and what was left of the meat was a dust that looked like cigarette ashes. Time for some decent pads. :)

For those who want to know.

The Cobra Rears are the Same caliper , with a Vented bigger rotor of course. 10.5in rotors for GTs (non Vented) and 11.65in rotors for Cobras.

They also used a different caliper brackets on the caliper themselves. The cobra one runs all the way across the front of the caliper where the Gt one is split. However there is no need to switch to the Cobra one unless you want to. If you ever rebuild your rear brakes, whether you keep GT size or switch to cobra, you might as well switch to this Cobra bracket as well. Just my opinion, though it's not "needed". Parts stores carry this part.
21_cal_comparsn.JPG


The larger Cobra brakes use a different mounting bracket which has to be installed on the rear end. So axles must come out.
caliperbrkt.jpg


If you already have Gt stuff. All you need is the mounting bracket on the rear end, the thinner Cobra Specific pads (worn a bit thinner than stock GT pads work too), and cobra rotors.

The reason Cobra Rear use a thinner pad is the vented rotor is a little thicker than the GT rotor.



Edit: I edited this to make more sense for everyone. Also added pictures.
 
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RichV

RichV

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^Thanks! You can buy the Cobra rear brake upgrade which comes with everything you need including anti-moan brackets and dustshields. But yes, the axles need to come out for this upgrade. I don't remember why, but I had to modify my rear brackets to make them work. IIRC, it had something to do with the wider rotor and that GT bracket needed clearancing for the rotor.
BrakeKit.jpg


Also, took this pic of my Wilwood setup with almost 2 full weekends of racing. They have about 3.5 driving hours on the pads, I'd say they are about 30% worn.
DSC06233_zpsd511194a.jpg
 

ProKiller

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Cpotts13

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what's this about thinner pads? i'm doing this conversion right now and it doesn't look like the HPS pads i bought are going to work with my gt calipers/brackets. so would i need cobra pads?
http://www.americanmuscle.com/hawk-1994-2004-mustang-cobra-bullitt-mach1-rear-brake-pads.html


Like mentioned above, the cobra caliper and the gt caliper are the same. You will need to buy cobra pads because they are thinner to accommodate the thicker vented cobra rotor.
 

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