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So, I decided to go with 13" stoptech brakes for my fox. I originally was going to go with the 2300x cobra r brembo but the stoptech seemed like a much better setup to me. But what do I know! Anyway, I was looking at replacement cost of stop tech rotors compared to 13" cobra rotors and it's nearly $650 for the stop tech, About 3-4 times th cost of cobra. Now, are those stop tech rotors gonna last 3-4 times as long as 13" cobra rotors???? If not, I might rethink my decision. This is for my 85 that I'm turning from street to HPDE car. I'm installing a cage, seat and harness as well as the BB setup. Thanks
 

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I buy my Cobra rotors to go with my R calipers at O'Reilly for about $50 a set and get about 6-8 track days out of each set. A few years ago I started looking at something bigger/better and decided I wouldn't live long enough to recoup the cost of expensive 2 piece rotors no matter how long I live or how long they last. The only advantage for the 2 piece for me is that I wouldn't be changing them as often. For the money I'll twirl the wrenches.
 

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I buy my Cobra rotors to go with my R calipers at O'Reilly for about $50 a set and get about 6-8 track days out of each set. A few years ago I started looking at something bigger/better and decided I wouldn't live long enough to recoup the cost of expensive 2 piece rotors no matter how long I live or how long they last. The only advantage for the 2 piece for me is that I wouldn't be changing them as often. For the money I'll twirl the wrenches.
Excellent info. The stoptech kit I purchased is back ordered for 6 weeks so
I started researching more and discovered the replacement rotors are $650! That's almost a set of tires. Are you running cooling ducts? Is the car you're running an '03 as in your signature? It's probably heavier than my fox too. What tracks are you running at.?
 

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Excellent info. The stoptech kit I purchased is back ordered for 6 weeks so
I started researching more and discovered the replacement rotors are $650! That's almost a set of tires. Are you running cooling ducts? Is the car you're running an '03 as in your signature? It's probably heavier than my fox too. What tracks are you running at.?
Yep the mach1. Cooling ducts and titanium shims behind the pads. VIR and CMP mostly and CMP is murder on brakes. You will be fine with the Rs.
 

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I swear I posted this last night, but I don't see it, so let's try this again...

The ST rotors should last longer, but I'm not sure about 3-4x as long. They're thicker (32mm vs 28mm), and being 2-piece they'll handle the thermal stresses better. (MFE has posted a number of times about rotor cracking issues, pretty sure that was with 1-piece Cobra rotors.) Whether that's worth the added expense, I don't know.
 

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Thanks Patrick, I'll do another search on the subject. Is it advisable for these type of high performance rotors to be turned? I'm sure less material doesn't help thermal properties.
 

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I'm going to post some speculation here, it may be total bull####, but it's well-considered bull#### LOL.

I'm generally in the Blurr camp...for as cheap as the cobra rotors are, and as generous as the return policies are, and as cheap as I am, I'll keep a-changin' them. No matter WHAT I've tried, they crack before they wear out. The spares I take to every event make also make great EZ-up canopy weights, so there's that.

However, from what I've gleaned over the years, the kits like the one you bought offer at least two very big advantages from a rotor-longevity standpoint alone: 1) Way better pad/rotor contact area. The Cobra setup concentrates its pad area, and therefore heat source, in the outer 2/3 of the rotor face. The damned things don't have a chance. 2) The 2-piece rotor design offers better thermal management in the first place, as Patrick pointed out.

With modern pad compounds that don't abrade rotors like the old standby Hawk Blues of 20 years ago, the rotors won't wear as quickly, and I'm pretty sure you'll enjoy many, many times the lifetime braking performance and crack-free durability that will make your investment worthwhile.
 

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I swear I posted this last night, but I don't see it, so let's try this again...

The ST rotors should last longer, but I'm not sure about 3-4x as long. They're thicker (32mm vs 28mm), and being 2-piece they'll handle the thermal stresses better. (MFE has posted a number of times about rotor cracking issues, pretty sure that was with 1-piece Cobra rotors.) Whether that's worth the added expense, I don't know.
At $650 a set they will have to last 26 times longer to break even so as I said before the calculator says keep twirling the wrenches.
 

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I run the one piece Cobra “white box” rotors with Wilwood calipers on the front of my CMC car and get 3-4 weekends out of the rotors. I have not had one fail in the hub area... they heat crack on the face. Last week I was at t500hp’s shop helping him out with a few things on his CMC car... he was the CMC National Champion in 2015 and runner up in 2016... he has the Stoptech set up on his car. As I was looking at the rotors on his car he informed me they have been on the car for a year and a half. I don’t know how many race weekends that is but he has ALOT of track time on those rotors and they still looked good.
 

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Interesting, and I like brake discussions. I'm a mail man, so I know how to burn up some brakes myself.

I will be looking for better brakes for my Fox chassis Lincoln, after I get the SN95 Cobra brakes on it. Are all of the calipers for SN95's or 13" brake kits about the same area size, the piston area?

I had a heck of a time locating any caliper big enough for my 98 Explorer(Mountaineer), since OEM was large(dual 1.75") pistons. I tried old Corvette calipers(four 1.875" pistons), but those had small pads like stock. I did pay good money for Todd(TCE) to make me some custom rotor hats. I love these rotors I have been running for almost ten years, 12.75 x 1.25" thick, from Coleman Racing. I recommend any two piece rotor, and Coleman can make almost anything. What I've been using run close to $150 each now, I think $140 was about what I paid before.

My Lincoln could use a bigger caliper than the OEM Cobra calipers, so is there one that's bigger, or some aftermarket caliper replacement that's larger? I'll be okay with the pads they come with, this car will be street only. I'm just hard on brakes.

I do have a caliper that I'm going to again custom build a bracket for, to get on my mail truck. These would work for a Mustang, if the piston size wasn't too much(these have six, about 5.44 square inches of piston area). The pads I love, huge but not quite the super high dollar caliper size, still .800" thick pads. This is a Wilwood GN III caliper, $315-360 on Amazon; https://www.amazon.com/dp/B002G35RT8/_encoding=UTF8?coliid=I3GJT1W3IUMF8T&colid=32X1ZA2MRI77P
 

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However, from what I've gleaned over the years, the kits like the one you bought offer at least two very big advantages from a rotor-longevity standpoint alone: 1) Way better pad/rotor contact area. The Cobra setup concentrates its pad area, and therefore heat source, in the outer 2/3 of the rotor face. The damned things don't have a chance. 2) The 2-piece rotor design offers better thermal management in the first place, as Patrick pointed out. .

That alone could trigger some to consider running the GM style PBR calipers with 2-peice 1.25" thick rotors.

Would certainly improve on spreading the pad area out over the entire surface of the rotor, and the design does allow for the use of 1.25" thk rotors.

Although from a cost perspective, the GM pads and standard Cobra 13" rotors would still be darn cheap
 

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I have the 13 inch Stoptech kit and really like it. With 525 HP I was beating on the Cobra brake package pretty hard. During my research I read that the 13 inch Brembo setup was good but the Stoptech kit was better. Reportedly the balance with Cobra rear brakes was superb and I can confirm that it is. Rotor rings are not cheap though as noted.
 

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I have the 13 inch Stoptech kit and really like it. With 525 HP I was beating on the Cobra brake package pretty hard. During my research I read that the 13 inch Brembo setup was good but the Stoptech kit was better. Reportedly the balance with Cobra rear brakes was superb and I can confirm that it is. Rotor rings are not cheap though as noted.
For the rotor "ring" contact Coleman Racing, and ask them how much it'll cost for the rotor. They will need to know the bolt circle and thickness, but they can make almost any rotor you can describe, in a day or so.
 

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I have the Stop Tech ST 40s with 14" rotors on my 86 fox. I too was surprised by the replacement cost for the rings. However a little research can yield a pair for a little over $400 shipped with hardware (Amazon Prime). And there is Coleman too.

Since I had the Cobra fronts on the 86, for my needs I didn't see any advantage to upgrading to a 4-6 piston caliper unless I was increasing the rotor size too. That ruled out any 13" set-up. Then I found a great deal on the ST-40/14s. Since I already had my wheels (11x18 CCWs), I checked clearance with the ST caliper template. Plenty of room so I picked them up. These calipers are massive - they look to be the same dimensions as my 2016 GT PP Brembos, but two fewer pistons. Easy to swap pads too. And the ST rotor/hat combo at 14" and thicker, is lighter than the blank stock 13" Cobra rotor too. With my very unscientific measuring (bath scale), the ST setup is a pound or two lighter per side than the Cobras. Another consideration besides the benefits of larger pad contact, more even pad distribution, and better heat control.

While I haven't been out with this new set-up, I hope they aren't as sensitive as the '16's Brembos. I've had to relearn brake touch and modulation with the '16. Once learned, however, those are very impressive "stock" brakes. And these 15" rotors are not cheap either.
 

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The harder you are on the brakes, the greater the difference in rotor life between a Brembo one piece rotor and a StopTech two piece rotor. For a typical driver, I would say the difference in life is around 3:1.

The other not so obvious advantage is that the StopTech caliper has better pedal feel than the Brembo caliper due to the stiffer design.

qtrracer,

The 14" StopTechs won't be more sensitive than a M-2300-X or Cobra PBR setup. As the rotor diameter increases, StopTech correctly uses smaller pistons in the calipers to compensate, keeping the brake bias constant.
 

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The aftermarket brake kits are made to equal stock brakes, and not to dramatically increase braking power. That's due to liability worries. When I built custom brakes for my SUV, I researched and asked for guidance from several people in the industry. Todd of TCE was the most helpful, and he got me the custom rotor hats I needed.

The first attempt I made with 65-82 Corvette calipers was good, a little more than stock brake power. The aftermarket would have chosen smaller pistons, such as the SSBC units I went to next as a slight reduction(45mm pistons versus 1.875"(about 49mm). This is very close to ideal, nearly stock but a hair more, but, the pad sizes are too small for heavy duty use. Try very very hard to put pad size and quality/choices, as the top priority for any brakes. You don't want to have to do brakes two or more times a year.

What I built is for any 95-01 AWD/4WD Explorer, but the updated 01+ Sport spindles for the 2nd gens, will allow a 1" larger rotor. So the stock 01+ Sports have 12" rotors instead of 11", a common idea Explorer guys know. So if someone had a crazy heavy wheeled truck and needed lots more brake, I could point them to the same parts, and they end up with 13.75" rotors. That would be way too much for any stock type truck, but it's the kind of big brakes large F-series trucks use.

You need good balance in your brakes, not too much, never less than stock, and with plenty of pad life given common parts. High end rotors can last for ages, pads never do.
 

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Well I'm on the fence right now. I currently have a 92 Fox body with the Cobra front/rear brakes. I am seriously debating laying out the cash for this Stoptech 13" kit but I'm reluctant to pull the trigger on it. It's a lot of money when I need to buy so much other stuff to get this car ready for CMC next year. My original plan was to remove the front Cobra calipers to go on my 2001 GT and put the Wilwood Superlite 4 piston calipers on the CMC car. It's a cheaper option by far than going the Stoptech route but I like the 2 piece rotors and the fact the Stoptech rotors are 1.25" wide compared to the 1 piece Cobra which are 1.1" wide....

Decisions, decisions......

Jamie
 

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Well I'm on the fence right now. I currently have a 92 Fox body with the Cobra front/rear brakes. I am seriously debating laying out the cash for this Stoptech 13" kit but I'm reluctant to pull the trigger on it. It's a lot of money when I need to buy so much other stuff to get this car ready for CMC next year. My original plan was to remove the front Cobra calipers to go on my 2001 GT and put the Wilwood Superlite 4 piston calipers on the CMC car. It's a cheaper option by far than going the Stoptech route but I like the 2 piece rotors and the fact the Stoptech rotors are 1.25" wide compared to the 1 piece Cobra which are 1.1" wide....

Decisions, decisions......

Jamie
Jamie... you can get the Wilwood Superlites that will accept a 1.25 rotor. Wilwood has various hats so you could probably put something together with the 1.25 rotor... or, you could keep your current Wilwood calipers and go with a two piece 1.1 rotor.
 

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ChristophrC, I may well have to look into that option. I see the Superlite calipers are available for 1.25" thick rotors, however I have no idea what size hat I would need to keep the rotor in line with the caliper. I'm thinking the caliper would also need to be shimmed back by half the extra distance (.15") of the rotor thickness.
 
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