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Huge brake upgrade for S197 chassis

1,150
1,125
In the V6L
I bought remanufactured Motorcraft ## BRCF430 and BRCF431 from Rock Auto. They are identified as 2015+ Mustang PP calipers.
Well, from what I see on the various websites, it should fit. Pictures, as @Coz said, would be very helpful. Does the spring fit ok with no pads in the caliper? Are you assembling it the way it's shown at 11:00 minutes in this video?:

It's possible it's a pad backing plate problem - wrong shape or something - unlikely but possible - shape issues happen with GT350 calipers, although it's not generally a problem.
 
Or if I put the pins in correctly. 😒

View attachment 82330
The pins go in flush. The wings on the clip look bent and should clear the pad tabs were the pins go through. I run the clips with the tabs up just like you have them. Sent the bottom pin. Hook the clip underneath the bottom pin. Bend down over the cross bolt. Send the top pin. If you having issues with that clip set maybe try Optimum Performance for a set of hardware. Here's a screenshot from page 21 in this thread that shows how everything sits. https://trackmustangsonline.com/threads/huge-brake-upgrade-for-s197-chassis.11867/page-21
Screenshot_20221231_212025_Chrome.jpg
 
198
157
Exp. Type
Autocross
Exp. Level
Under 3 Years
Colorado Springs
I do feel I'm at the limit of the 4P capabilities, even with the Boss 302 brake duct kit on my '05 GT. I want to see how this "fresh start" will perform. VIR will see 100mph drops twice per lap, and CMP is traditionally hard on brakes. There's time and distance to get them cooled down at both venues, but I'm right at 4,000 pounds (car and driver) and over 600hp, so that is the challenge.


Do you run with ABS on or off? Mine "broke" for a to be determined reason, and with the 6Pots I found it was very easy to lock up without ABS. Was told "it will make you a better driver without", and I am not going to argue that, but it locked up very easy.
 
198
157
Exp. Type
Autocross
Exp. Level
Under 3 Years
Colorado Springs
Or if I put the pins in correctly. 😒

View attachment 82330


My car isn't outside, else I'd check, but I thought the main long clip sat on the recessed part of the pins, not half on the more fat section. Again, going from memory, but they went together poorly for me, then had to reassemble and it was fine. And those ears definitely look deflected in the images.
 
5,757
6,882
Exp. Type
W2W Racing
Exp. Level
20+ Years
Pleasanton: 1/2 way between Sonoma and Laguna Seca
Do you run with ABS on or off? Mine "broke" for a to be determined reason, and with the 6Pots I found it was very easy to lock up without ABS. Was told "it will make you a better driver without", and I am not going to argue that, but it locked up very easy.
I can tell you from experience that running with the ABS off is very difficult. My entire racing career was in non ABS cars and I had no problem managing that but a car that was designed for ABS with the ABS disabled is far more difficult to drive, exasperated by the addition of power brakes. If you watch any of my racing videos you see that I am often locking up one or more wheels which is hard on lap times as well as on tires. My mission for 2023 is to retrofit a later year ABS into my system as the coyote control pack does not talk to my early 3 valve ABS brick.

E775BBA4-1CCF-4719-B562-ADB1345063C2.jpeg
 
198
157
Exp. Type
Autocross
Exp. Level
Under 3 Years
Colorado Springs
I can tell you from experience that running with the ABS off is very difficult. My entire racing career was in non ABS cars and I had no problem managing that but a car that was designed for ABS with the ABS disabled is far more difficult to drive, exasperated by the addition of power brakes. If you watch any of my racing videos you see that I am often locking up one or more wheels which is hard on lap times as well as on tires. My mission for 2023 is to retrofit a later year ABS into my system as the coyote control pack does not talk to my early 3 valve ABS brick.

View attachment 82332


Not gonna lie, that makes me feel better. It's getting fixed, but I was not looking forward to having to add that to the learning curve.

That is a sexy pic tho.
 

Mad Hatter

Gotta go Faster
4,862
3,712
Santiago, Chile
Having ABS is a God send, Have a lot of off road experience, and used to always ask for a ABS "off" switch in my jeeps. But absolutely love the abs on the Boss. Braking deep into the corner is a great advantage. Don't think I would have so much fun without it.
 
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3
0
Exp. Level
Under 3 Years
California
Hey guys, wasn't sure where to post this but figured some might find it helpful. I have a set of 18x9.5 +35 Enkei RS05RR (no spacers) on my 2014 V6 which I am in the process of installing 6 piston Brembos on. They seem to clear pretty well. The back of the spoke to the highest point on the caliper is about 4-4.5mm and the caliper-barrel clearance is about 3mm-4mm. Both of these are just within the allowable clearance specs from what I understand. Don't mind the ridiculously stretched tires from the previous owner of the wheels.

tempImagelVZyLJ.pngtempImagebwvejt.pngIMG_1737.pngtempImageQV4bLE.png
 
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cholmes1

400lb Gorilla
315
174
Denver, CO
Some potentially useful notes for those in S197s considering the S550 PP swap. I used the below along with member input to decide that '13-'14 GT500 calipers were the best option for my '13 Boss.

Overall, given that the S197 has a smaller master cylinder, different front caliper areas, and different rear caliper areas from the '15+ PP Mustangs, it seems like it would be an easy way to achieve unexpected results or failure in a critical system.

Brembo caliper piston specifications (acknowledgment to @Merkyworks and @Cman01 on SVT):

Caliper Piston Diameters inches (mm)
  • 07-12 4 Piston Boss 302/GT500: 1.73, 1.57 (44, 40)
  • 13-14 6 Piston GT500: 1.50, 1.34, 1.18 (38, 34, 30)
  • 2015 GT PP 6 Piston: 1.417, 1.417, 1.417 (36, 36, 36)

Caliper Piston Area (one side of caliper)
  • 07-12 4 Piston Boss 302/GT500: 4.30 in^2
  • 13-14 6 Piston GT500: 4.26 in^2
  • 2015 GT PP 6 Piston: 4.73 in^2

The uniform pistons in the S550 are a cause of some concern as well, as you would see premature wear on the leading edge of the pad. That effect would be accelerated in race/hard driving applications. The '13-'14 GT500 has a staggered piston design similar to the OE Boss caliper. We also use the same master cylinder and rear brake caliper.

Pairing the uneven wear with our reduced-strength master cylinder (S197 is 1.063" v S550 is 1.125". The MC change in the S550 was done to address both the front and rear caliper changes). There are too many compromises in my view for those planning to swap the front S550 PP calipers and then travel at high speeds.

Caliper Piston Size Explained.jpg
 

Mad Hatter

Gotta go Faster
4,862
3,712
Santiago, Chile
Oh well.. what ever works for you. I, for one am delighted with the S550 setup. I do tend to use the pads to the last mm and with great results and pretty even wear. Would say they are better then a set of 15" Stoptech st60 trophy brakes that my friends S197 uses, The S550 Brembo surface contact size is much, much bigger. Since the car has race pads the little extra brake travel is a good thing.

Then again, my Boss is really only used at high speeds and is seldom street driven. The S550 brake setup lets me out brake Cayman GT4 cars, so can't complain about that!!!

Big fan of this setup as you might be able to tell!! :hellyeah:
 

cholmes1

400lb Gorilla
315
174
Denver, CO
Oh well.. what ever works for you. I, for one am delighted with the S550 setup. (The) S550 brake setup lets me out brake Cayman GT4 cars, so can't complain about that!!!

Big fan of this setup as you might be able to tell!! :hellyeah:

Great feedback and there is zero doubt regarding the pad size on the PP calipers. If you have a setup that is working well for you in regular race use, that is awesome. I know many members have had success and reported similar braking gains with no concern on pedal travel.

My comments above were certainly not to disparage those using the S550 setup successfully but to add to the conversation for those deciding. I initially thought the S550 was the ideal solution for my needs, and the fact that it is cheaper than the GT500s setup made it all the better.

However, after going through the complete thread and doing some research for my concerns, it’s just not for me.

I hope your S550 setup gives you years of trouble free service Mad Hatter
 

steveespo

Lord knows I'm a Voodoo Child
Moderator
3,850
1,473
Exp. Type
Time Attack
Exp. Level
10-20 Years
Cookeville TN
Great feedback and there is zero doubt regarding the pad size on the PP calipers. If you have a setup that is working well for you in regular race use, that is awesome. I know many members have had success and reported similar braking gains with no concern on pedal travel.

My comments above were certainly not to disparage those using the S550 setup successfully but to add to the conversation for those deciding. I initially thought the S550 was the ideal solution for my needs, and the fact that it is cheaper than the GT500s setup made it all the better.

However, after going through the complete thread and doing some research for my concerns, it’s just not for me.

I hope your S550 setup gives you years of trouble free service Mad Hatter
I have used both the GT500 and S550 calipers on my S197 and found that the GT500 calipers, using the same Pagid or Carbotech compounds could not shed heat and were subject to fade during longer 20+ minute sessions. And yes the S550 combination does have a longer pedal.
 
Or if I put the pins in correctly. 😒

View attachment 82330
Not sure what you have going on there but it should not look like that. Either the hardware or pads are not allowing things to line up properly.
ALSO: When installing these parts install the top pin first with the clip, THEN you can compress the clip to slide in the lower pin. I think you may be trying to install the clip after installing the pins.
1673028358123.png
 
198
157
Exp. Type
Autocross
Exp. Level
Under 3 Years
Colorado Springs
Not sure what you have going on there but it should not look like that. Either the hardware or pads are not allowing things to line up properly.
View attachment 82522


THANK YOU! That is what I was getting at, the long plate sits inside the narrow diameter of the pins, not on the larger shoulders. My stupid car is still at the shop (I'd be harassing them, but I don't think I can get it up the snowy hill right now so....).
 

Mad Hatter

Gotta go Faster
4,862
3,712
Santiago, Chile
I have used both the GT500 and S550 calipers on my S197 and found that the GT500 calipers, using the same Pagid or Carbotech compounds could not shed heat and were subject to fade during longer 20+ minute sessions. And yes the S550 combination does have a longer pedal.

Very true, I usually can start to out braking the GT4 cars in the last laps of the race once their brakes start to fade...

As far as the pedal feel, maybe the GT500 option could be the best bet for a mainly street car, running on regular pads.
 
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My concern isn't just the long pedal but also reports of an inconsistent pedal. I read about the first press of the pedal being long but then it might or might not pick up at a higher or different spot on a second quick application.... that kind of inconsistent feedback and lack of precision sounds tricky and sort of annoying especially if you're in the midst of a downshift. I can see how the tradeoff is worth it for reduced fade in a full-tilt race car but for my purposes it doesn't sound worth the aggravation.

BTW it's nice to see the honest and objective feedback on this mod in this thread. The lack of confirmation bias is refreshing.
 
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