I love that they use “Mu” for brake pad friction we use it in aviation for runway friction on landing. I never understood what it actually meant but i know it’s directly proportional to friction lol

TeeLew said:

You don't need much mu on the front of the car and significantly less on the rear. A higher friction level doesn't increase braking performance, it just makes the ABS come in sooner.

Modulation is a much bigger deal than ultimate friction level.

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Only because the factory "street" ABS is dog sh*t. The S650 and the new Dark Horse SC have much better and modern ABS. It took me a while to figure out what was going on with the ABS thanks to Terry from Vorshlag to actually posting it in a way that clicked with me. The aggressive GLoc pads were never working because the ABS was fighting them in every brake zone to a point where the Ice Mode kicked in. Now with the lower Mu pads it's much easier to control the car in the brake zone and to stay on them for long.

bnight said:

That chart is what I used when I selected the OEM PP1 pads for rear (DS2500) and DSUno (Red) for front.

Click to expand...

This is going to be my setup as well - how do you like it? Any other advice or feedback to share?

TeeLew said:

Yep, and they really fight rear locking. ABS can only do so much, especially since they all run the torsen, which screws you for braking. There just isn't enough diff lock to keep things happy.

In general, any sort of front-engine GT-ish car wants very little braking on the rear. I haven't tried it, but I suspect the EBC blue (orignal) would be too much for the rear. The DS2500 really drops over about 350*. That's going to be about the temperature on brake application. 1/2 way through the brake zone, they'll be 550-ish. That's kinda the idea of a digressive rear pad. Good initial friction, then have the friction level drop through the zone so you don't have to fight locking on corner entry. A friction coeff. of about 0.30-0.35 is what you're looking for on the rear coupled with something in the 0.45 range on the front. Any of the big friction pads on the front will be a like a light switch, on/off.

You don't need much mu on the front of the car and significantly less on the rear. A higher friction level doesn't increase braking performance, it just makes the ABS come in sooner.

Modulation is a much bigger deal than ultimate friction level.

Click to expand...

I agree, and prefer more smooth modulation rather than on/off switch. Not sure why anybody would want the on/off switch other than a misconception of better/stronger braking. Reminds me of those throttle booster gimmicks lol

How hot is too hot for the DS2500? I run them front and rear as of now, and I can definitely feel performance degradation near the end of the 20 minute session if I’m not managing temps with cooldown laps.

Do you guys smell brake burning after sessions? I do!

Rodpwnz said:

This is going to be my setup as well - how do you like it? Any other advice or feedback to share?

Click to expand...

My last track day was on really brake intensive track. And I was mighty impressed with how that brakes package performed as people were struggling with brakes. The DSUno is very easy to modulate but also aggressive and with great stopping power. I was sharing the box with a friend of mine who has a G80 M3 with over 600 WHP and while his lap times were faster we were actually posting similar 180-120 km/h braking times. He got his rear pads on fire (Pagid RSL29) while my DS2500 was performing great. So overall I'm happy with that package and for example compared to Gloc R16/R12 combo I was running previously and Serres the car was actually over slowing for T1 by 0.5 seconds because this was the first time I was driving the DSUno/DS2500 combo. In other words that combo is very aggressive and very good and I don't think my car ever braked better. After my last event I replaced the Brakes Booster and there is a difference in the boost to the brakes so I guess I will be stopping even better.

So what was wrong with the Gloc 16/12? That was recommended to me by Tim at OP mustang for my Dark Horse. Over braking the rear?

bnight said:

Only because the factory "street" ABS is dog sh*t. The S650 and the new Dark Horse SC have much better and modern ABS. It took me a while to figure out what was going on with the ABS thanks to Terry from Vorshlag to actually posting it in a way that clicked with me. The aggressive GLoc pads were never working because the ABS was fighting them in every brake zone to a point where the Ice Mode kicked in. Now with the lower Mu pads it's much easier to control the car in the brake zone and to stay on them for long.

Click to expand...

I wish I had saved the link, but I read somewhere that the Dark Horse with handling package was able to decelerate at 1.4G without the ABS overriding. This (and the tires Ford chose) is why it had the shortest stopping distance of any production car in the history of Motor Trend.

I could not get the ABS to activate at Road Atlanta, pushing the brake pedal hard, although not stabbing the pedal quickly, just squeezing it with a lot of pressure. I know it is brake by wire, but still. Unless the Dark Horse ABS is magical and cannot be discerned by a driver who can tell when it is activated in every other car I have ever driven (including police cars where I have activated it at triple digit speeds in hairy situations), then it never came on. If it is super secret ABS that can activate discreetly without me ever knowing, then I stand corrected. But I suspect it does not activate with hot, sticky tires and hard pedal application on a dry, hot track.

Ah, found it. The 1.4G link.


Quote:
"Now, let's put this into perspective. To achieve such an incredible feat, the Mustang Dark Horse had to decelerate at an average of 1.4 G's. That's like being hit with a gravitational force that would make your head spin. This car is in a league of its own, as no other vehicle has ever come close to achieving this level of stopping power."

The stock pads should be pretty good then. When mine go ill try the glocs and see what happens

bnight said:

Was constantly fighting the ABS Ice mode (OEM ABS module intervene once you are past 1.2G of braking)

Click to expand...

So this S550 quirk appears to have been addressed, at least on the S650 Dark Horse with handling package.

.

Gunslinger55 said:

The stock pads should be pretty good then. When mine go ill try the glocs and see what happens

Click to expand...

Please do not forget to take some photos of the back of the original pads, so we can figure out what Ford installs at the factory.

Yep for sure i’m curious as well

We will see after 9 sessions this weekend

Gunslinger55 said:

So what was wrong with the Gloc 16/12? That was recommended to me by Tim at OP mustang for my Dark Horse. Over braking the rear?

Click to expand...

Fronts almost zero modulation constant ABS activation on street tires so 16 are too aggressive for street tires. Rears also too aggressive but I was having ABS issues even with R10/R8 then I switched to R12/R8(same rears) and the ABS issues become even more and with 16/12 was insane.

Dracon with different setups 180-100 km/h times:




On Serres since turn 1 is over 100 km/h I measured 180-120 km/h:



All of this data is collected with Racebox from GPS. As you can see the DSUno/DS2500 combo is much faster to brake compared with Gloc R16/R12 and is really clear how going up in Front compounds actually net worse results. I spend tons of money on brakes the past 3 seasons and I really hope I found a solution as it was a nightmare.

Rodpwnz said:

This is going to be my setup as well - how do you like it? Any other advice or feedback to share?



I agree, and prefer more smooth modulation rather than on/off switch. Not sure why anybody would want the on/off switch other than a misconception of better/stronger braking. Reminds me of those throttle booster gimmicks lol

How hot is too hot for the DS2500? I run them front and rear as of now, and I can definitely feel performance degradation near the end of the 20 minute session if I’m not managing temps with cooldown laps.

Do you guys smell brake burning after sessions? I do!

Click to expand...

You'll boil the fluid before you fade the DS2500. Keep an eye on wear. Measure the pads before and after running. If you see any negatives from high brake temp, it will be excess wear.

Some cars can take those big friction numbers. Think about this in a different way. Don't think of it as trying to lock the tire. Think of it as trying to convert kinetic energy to waste heat as quickly as possible. To transfer as much energy as possible, the disc can't stop. The friction of the pad is just something that has to be matched with the hydraulic package and the ultimate capacity of the car wrapped around it. Brake discs have gained a lot of radius in the last 10 years. A lot of these High mu brake pad materials were formulated around much smaller discs. The really high mu pads were built for Champ/Indycar when they had steel discs and NASCAR cup cars when they had 15" wheels and 13" discs. Those hydraulic systems were doing a lot of work. Getting help from the pad material was a big deal. The energy being dumped into a disc of a Cup car at Martinsville or a Champ car on a street circuit was impressive. They worked on the GT cars of the day, because they had undersized discs and you would size the hydraulics as needed. The problem with big mu pads is they often get 'sticky' at the end of the brake zone and fail to release the disc nicely. This can cause front locking or entry instability from the rear.

As racing has migrated to ABS in GT cars and carbon in the fast stuff, the pads are now being created best work with the ABS systems. Discs have grown over the last 10 years and so have calipers. They need to have very good modulation characteristics so the ABS can control the tire slip and optimize stopping power without sliding the tire excessively. The pad ultimate friction level is not the advantage it once was.

bnight said:

Fronts almost zero modulation constant ABS activation on street tires so 16 are too aggressive for street tires. Rears also too aggressive but I was having ABS issues even with R10/R8 then I switched to R12/R8(same rears) and the ABS issues become even more and with 16/12 was insane.

Dracon with different setups 180-100 km/h times:

View attachment 109736


On Serres since turn 1 is over 100 km/h I measured 180-120 km/h:

View attachment 109737

All of this data is collected with Racebox from GPS. As you can see the DSUno/DS2500 combo is much faster to brake compared with Gloc R16/R12 and is really clear how going up in Front compounds actually net worse results. I spend tons of money on brakes the past 3 seasons and I really hope I found a solution as it was a nightmare.

Click to expand...

First, this is some really cool testing you've done here. Second, boiling SRF is impressive. Time to increase the ducting. I don't know if you left foot brake, but be careful of crossing pedals if you do (both at the same time as you transition between the two). That puts a lot of unnecessary heat into the brakes.

TeeLew said:

First, this is some really cool testing you've done here. Second, boiling SRF is impressive. Time to increase the ducting. I don't know if you left foot brake, but be careful of crossing pedals if you do (both at the same time as you transition between the two). That puts a lot of unnecessary heat into the brakes.

Click to expand...

Thanks I don't left foot brake but stopping 1800 kg ( 3968 lbs) car from 200 km/h (124 mph) takes a lot of toll especially when your brake pads are triggering ABS and spending so much more time on the brakes. My tracks are very short 1.86 miles and they have a lot of brake zones: Dracon has 5 stops and the longest straight is a 1/4 mile. So the brakes just don't have time to cooldown in a lap. Which is why after struggling for a few seasons and SRF showing signs of boiling I decided to check the data to quantify what exactly was going on. What prompted that research was Terry changing the ABS on Trigger. So I found some brake zones and run through my best laps over the years to figure out what was going on. Dracon got changed in 2024 which changed the data. And so was Serres but the R16/R12 vs DSUno/DS2500 happen on exactly the same car in the span of 2 months in September/November 2025 on a brand new A052 tires. In fact my Serres 1:27.86 lap time actually was loosing 0.5 seconds in the brake zone on Turn 1 just because braking from the R16/R12 marker over slowed the car.



This is exactly why having great data system is beneficial to unlock more lap time and inside to what is going on with the car. Cool thing is that we all run Racebox and exchange data between us all the time.

bnight said:

That chart is what I used when I selected the OEM PP1 pads for rear (DS2500) and DSUno (Red) for front.

Click to expand...

Do you drive with these pads on the street, too, or only on the track?

If so, could you tell us a little more about them?

Junkyard Dog said:

Do you drive with these pads on the street, too, or only on the track?

If so, could you tell us a little more about them?

Click to expand...

I drive with them on the street as well but drive is very strong word it's mostly from/to the track or from/to Dealer of my tires shop. At that point of the life of the car I very rarely use it on the street. But yeah they are streetable pads and they don't make a lot of noises like Gloc so for a change my car doesn't sound like a train when it stops.

Ok, thanks. Ferodo says DS2500 is ok for road use, but DSUNO "is not suitable for road use." The DS2500 is the only Ferodo pad that does not have that warning.

Just for reference, an Essex rep giving Ferodo advice for heavy, fast BMW's like the M2 in this forum thread:

These guys basically say the 2500 does not hold up on the front and leaves deposits on the rotors when it gets hot.

And these guys say the same thing. The DS2500 disappears pretty quickly on the front (although it stops the car all the way through the session).


One post from that thread quoted below (from the Essex rep in North Carolina):

I just posted something about this topic over in the M2 forum...everything below applies with the e90 chassis. I wrote:

For the M2, the DS2500 would be marginal on the front of the car in some circumstances. As noted, every driver, track, and car is different. As such, what works for one person's situation isn't necessarily going to be ideal for another's. On one hand you may have a stock M2 on street tires, on Roebling Road, being driven by someone who is easy on the brakes. On the other hand you have a driver who is tough on brakes, driving Road America on Hoosier slicks, and he has added 50 HP. The difference between the brake demands in these two scenarios is tremendous.

As an overarching baseline recommendation, I'd consider the DS2500 a good street, AutoX, and very light track duty pad for the front of an M2 and M2 Competition. It should work well on the front and rear if you're on street tires, the car isn't juiced up with extra HP, the track is fairly easy on brakes, and the driver is average on brakes.

As a rear pad, the DS2500 is going to be fine with no issues under just about any conditions. You'll never get them hot enough on the rear of an M2 to cause any problems, regardless of what track you're on, tire choice, etc. Some of our brake kit customers leave the DS2500 in the rear calipers all the time, so they don't have to swap them out when going from track to street and back. The only issue with this strategy is that the DS2500 is lower mu than the DS1.11 or DS3.12. Running the lower mu DS2500 in the rear effectively increases the amount of work your front brakes need to do. That creates more heat in front brakes. That may not be a problem, or it may be...depends on the situation. One would really have to experiment to be sure.

The DS2500 does have a very high max operating temperature though. It's extremely rare that anyone will fade it. What happens more often, as others in this thread have noted, is that it starts to burn up very rapidly when it gets ridiculously hot. Fortunately, that is a nice/gentle failure mode, and doesn't end badly (vs. the pad giving up all mu and you not having a brake pedal when you step on it...which is not a gentle failure mode!).

If you are running race tires, have extra HP, are particularly hard on brakes, or you're driving a tough braking track, I'd suggest the Ferodo DS1.11 or DS3.12. They can both handle any amount of heat thrown at them, will never fade, etc.

The beauty of the Ferodo DS compounds is that you can swap them around on the same discs without having to re-bed them. For example, you run the DS2500 on street/autoX, then the DS1.11 at the track. If you were using pads from multiple manufacturers, the smart play would be to scrape the discs clean to get all the pad material off their face prior to bedding in the other pad compound. Otherwise you'd risk cross-contamination of the pads on the disc face, which leads to judder and vibration. With the Ferodo line, you don't have to worry about that. You just lay them down on top of each other and they play nice.