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Brake bias control??

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Sorry to say this but it looks like you reach the limit of the stock Brembo. Your next solution is to upgrade to race setup. Just make sure you get a caliper than can get a 1" thick pad.

I had the same problem last year. My front pads (Pagid RST-2) woulds only last 6-7H on a easy for brake track. I did kill one set in 4H at Indianapolis Motor Speedway. And my brake pedal was gone after 2-3 laps and I have 4" brake ducts.
I installed the AP Racing with the race ABS kit last winter and it's one of the best mod I've done so far. I can get 10-15H on the pads and absolutely no fade, even at IMS for the full 20min.
https://www.essexparts.com/essex-de...brake-kit-front-cp9668372mm-mustang-s197-0613
Ugh. 4500$??? I might as well move to a gt350. I'm surprised I'm having so much problems. I am an advanced driver but this is crazy. 3 hours max on pads . I need to dump 400 lbs or upgrade . will any 6 piston upgrade do the trick ? Id like to put 4 pistons on the rear too. Needs a bunch more brake.

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You can upgrade to the GT500 or S550 PP brake packages and there are a couple how to threads on the subject.

@steveespo

@captdistraction
 

ArizonaBOSS

Because racecar.
Moderator
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Arizona, USA
I went thru a full set of new pads in 2 days at gingerman. As well. Twice on 2 different weekends. 1:42-144 lap times at gman and 2:40 at RA.
I don't have the 302r and module. Gonna search for it right now and buy that damn thing . its gotta be eating my pads. My 1200 hp twin turbo viper didn't eat pads like this and I would hit 180 to 185 on the front straight and 155 into turn 5 and after the kink in to Canada corner. I could get a full weekend out of a set of pads easy. This mustang is ridiculous. I'd expect the cooling time would be better at RA. My temp gun was over 600 degrees on the rotors each session at RA and at Gman. Nuts!

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What pads are you running, and do you have brake cooling? These are big factors. The 4-pot OEM Brembos are OK, not great. Ti shims can help.

The most cost-effective recommendation here is the S550 PP brake upgrade package. Not sure the ultimate effectiveness of that on-track yet (not enough adopters w/ time on this setup for S197 in race application yet), but it seems promising!

The "final solution" like that Essex Setup or a Brembo Pro kit (what I run) is not cheap, but they are basically unflappable.
PFC front pads last an entire season, or Hawk Pads 3/4 of a season at half the price. Front 380mmx35 rotors last a season or more, my FTBR floating rear rotors have lasted almost two seasons at this point with minimal wear.
The Brembo Pro kit is the same things the IMSA and PWC teams ran on their cars.
 
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I started with carbotech 12s up front and 10s in rear. then went to 16 in front then 20s in front. The rears are still near new and the other 3 sets: 2 are to the backing plate, the 20s only had 3 25 min sessions at RA and are over 50% gone. I have had to replace the rotors with a new set to stoptech 1 piece slotted rotors with each set of pads because they were so heat cracked I would trust them for another weekend.

FYI-- I called carbotech to say WTF dude? and they told me specifically NOT to run the Ti shims. They said the backing plate acts as a heat sink and can transfer the heat out better without them.

I have the Vorshlag backing plates and 3" cooling ducts running to the fog light holes with the boss 302 duct things. They flow plenty and directly into the center of the rotor.

Is that brembo pro kit that much better than the stock 4 pot brembos? I am thinking surface area to surface area.... they are the same so how are they better? Do they run a larger pad?

Thanks!
 

ArizonaBOSS

Because racecar.
Moderator
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Arizona, USA
Replied to your PM.
Other notes--Regarding the pad size and swept area, it is similar to stock, if you use the narrow annulus friction ring (rotors) like I do. However you also have the option to run a wide-annulus rotor (and correspondingly taller pad in the same caliper) which will significantly increase swept area (rotor weight will also increase).

For stock calipers, I would recommend trying PFC or Pagid brake pads. Had issues with Hawk on the stock calipers, never tried Carbotech.
Run Hawk pads on the race calipers w/o issue--they stop great.

Assuming RA is Road America--that is a very tough track on brakes with at least 3 spots coming down from ~150mph to ~50-60mph. The thermal load has to go somewhere and it's probably nuking the pads you have.
 
Ugh. 4500$??? I might as well move to a gt350. I'm surprised I'm having so much problems. I am an advanced driver but this is crazy. 3 hours max on pads . I need to dump 400 lbs or upgrade . will any 6 piston upgrade do the trick ? Id like to put 4 pistons on the rear too. Needs a bunch more brake.

Sent from my LG-H918 using Tapatalk

One thing I can tell you about 4 piston in the rear is the stock axle shafts in these cars have an insane amount of flex to them. So much so, that when we put the Wilwood aero4 on the rear, the axle would flex enough in the turn that the rotor would contact the fixed caliper body. We wound up pulling the caliper, splitting it, and machining enough off to clear the amount the axle flexes. Crazy thing is we took off near .125" on the inside lower part to clear how much the flex was pushing the rotor into the lower part of the caliper. You do not notice this on stock rear brake or the gt500 upgrade as the caliper is mounted at 12 o'clock and is floating. The Aero4 we ran is mounted at 3 o'clock.

There seems to be a big difference in lifespan of the same brake product among different drivers. The car we have been working with had the pre-2015 Boss S Brembos up front and GT500 calipers/rotors out back and would cook a set of brembo rotors and 2 sets of pagid rst pads in about 6 hours of track time. I have seen people swear they get "half a season" from that setup. Obviously how hard you drive, power of the car, and size of tires is all going to play a roll in this too.
 
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Replied to your PM.
Other notes--Regarding the pad size and swept area, it is similar to stock, if you use the narrow annulus friction ring (rotors) like I do. However you also have the option to run a wide-annulus rotor (and correspondingly taller pad in the same caliper) which will significantly increase swept area (rotor weight will also increase).

For stock calipers, I would recommend trying PFC or Pagid brake pads. Had issues with Hawk on the stock calipers, never tried Carbotech.
Run Hawk pads on the race calipers w/o issue--they stop great.

Assuming RA is Road America--that is a very tough track on brakes with at least 3 spots coming down from ~150mph to ~50-60mph. The thermal load has to go somewhere and it's probably nuking the pads you have.
Its definitely eating the pads at Road America but also Gingerman too. The problem was worse at Gingerman because the heat boiled the Castro srf fluid and caused a no brake pedal situation . both days. So I need cooler running brakes or more efficient brakes that don't run so hot . since the rears are not helping at all, the 302r abs module outta help out my front brakes a bunch. Having larger pad area outta make them more efficient , requiring less use of the brakes. In theory anyway

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One thing I can tell you about 4 piston in the rear is the stock axle shafts in these cars have an insane amount of flex to them. So much so, that when we put the Wilwood aero4 on the rear, the axle would flex enough in the turn that the rotor would contact the fixed caliper body. We wound up pulling the caliper, splitting it, and machining enough off to clear the amount the axle flexes. Crazy thing is we took off near .125" on the inside lower part to clear how much the flex was pushing the rotor into the lower part of the caliper. You do not notice this on stock rear brake or the gt500 upgrade as the caliper is mounted at 12 o'clock and is floating. The Aero4 we ran is mounted at 3 o'clock.

There seems to be a big difference in lifespan of the same brake product among different drivers. The car we have been working with had the pre-2015 Boss S Brembos up front and GT500 calipers/rotors out back and would cook a set of brembo rotors and 2 sets of pagid rst pads in about 6 hours of track time. I have seen people swear they get "half a season" from that setup. Obviously how hard you drive, power of the car, and size of tires is all going to play a roll in this too.
That's excellent info! And I used to drag race a 1000 rwhp fox body and had to do some mods to the 8.8 to keep it from twisting too. Ill have to look into those mods again it seems. I do think I can afford a 4 piston rear if I had a 6 piston front and still maintain bias. I would like to keep my 18x 10 rims and 305 Pirelli slicks square setup. I'm going to have to likely make a custom setup for the rears but there is enough room to fit them

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That's excellent info! And I used to drag race a 1000 rwhp fox body and had to do some mods to the 8.8 to keep it from twisting too. Ill have to look into those mods again it seems. I do think I can afford a 4 piston rear if I had a 6 piston front and still maintain bias. I would like to keep my 18x 10 rims and 305 Pirelli slicks square setup. I'm going to have to likely make a custom setup for the rears but there is enough room to fit them

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We are currently running 335 rear and 325 front so there is a bit more grip which adversely causes more flex. I spoke with Moser and they have a set of alloy axles they claim will not flex nearly as bad/if at all, and at around $400 its a good option. The cortex axle is another option to overcome this, but at that cost, an IRS from a s550 could be retrofitted for just a bit more. I believe Wilwood is the only company currently making a bolt on 4 piston rear caliper (aero4). It also give you a shoe style parking brake inside the top hat so you can set it even if the brakes are not completely cooled as it does not use the pads....however, we had to back them off to the point of no longer working in order to clear the flexing axles...thanks Ford!
 
Sorry to say this but it looks like you reach the limit of the stock Brembo. Your next solution is to upgrade to race setup. Just make sure you get a caliper than can get a 1" thick pad.

I had the same problem last year. My front pads (Pagid RST-2) woulds only last 6-7H on a easy for brake track. I did kill one set in 4H at Indianapolis Motor Speedway. And my brake pedal was gone after 2-3 laps and I have 4" brake ducts.
I installed the AP Racing with the race ABS kit last winter and it's one of the best mod I've done so far. I can get 10-15H on the pads and absolutely no fade, even at IMS for the full 20min.
https://www.essexparts.com/essex-de...brake-kit-front-cp9668372mm-mustang-s197-0613
Are you running an 18" or 19" wheel with those 372mm?
 

ArizonaBOSS

Because racecar.
Moderator
8,730
2,734
Arizona, USA
@Drlee50 do you have any video of your runs from those tracks? If you are boiling SRF you either need to make modifications to your cooling, brake system, or driving style.
 
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@Drlee50 do you have any video of your runs from those tracks? If you are boiling SRF you either need to make modifications to your cooling, brake system, or driving style.
Yes I do have videos. Ill see if I can load up something on YouTube. I'm pretty damn fast....til I lose brake pedal. :)

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@Drlee50 do you have any video of your runs from those tracks? If you are boiling SRF you either need to make modifications to your cooling, brake system, or driving style.


Here is a video from last week. It was the last session of the day. Track was rained out on saturday. sunday morning sucked as well. after lunch i got out and ran 3 sessions.
This is the 3rd session. I trimmed the video- the first lap is not on there. It was a warm up lap for tires and tire pressures. This is lap 2. it was a 2:40 which was my best. I ran 5 laps at 2:40 between the 3 sessions. But as you will see, in lap 3, into turn 5, the brakes failed me. Couldnt get it slowed down in time for the turn. cooled em down a bit and finished the session but it began to rain again so I couldnt push it as hard as I normally would. You can still hear the brakes squealing even with light use because they are so hot. Got black flagged for the turn 5 incident . They said the corner workers thought my brakes were shot as well. I told them I went in hot as me saying my brakes were f****d would have ended my day for sure and I knew I could just take it easy and finish it out fine. I was black flagged at Gingerman as well as they said my brakes were glowing red at like 1pm on a sunny day. For them to say that, they must have really been hot. And they were as every session after a few hard laps the pedal would go lower and lower till I had to seriously take 2 cool down laps to get them back.
 

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