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Base S550 brake upgrade ABS programming

496
318
sfo
to since I have a base model GT, but the PP2 BB+MC, and sticky tires, I'll put it through its paces and report back. My PP2 friend loaned me their vin, so, here goes nothing.
I thought that one of the upgrades base guys did was put the larger front PP brembos on and that worked with no additional mods? On the GT line I thought all the BB and MC are the same? I thought the only different ABS programing was in the FP350s which is plug and play on a GT taking advantage of a grip provided by a stickier tire?
 

PaddyPrix

If breakin' parts is cool, consider me Miles Davis
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San Diego
I thought that one of the upgrades base guys did was put the larger front PP brembos on and that worked with no additional mods? On the GT line I thought all the BB and MC are the same? I thought the only different ABS programing was in the FP350s which is plug and play on a GT taking advantage of a grip provided by a stickier tire?
I'm curious to find out for sure. You can put on the 6 piston upgraded calipers, rotors, and pads, and it will work. Kinda. I'd still fade halfway through a session, but ACS is probably the most abusive braking track I know of.

As for what's the same ... eh? -- https://trackmustangsonline.com/threads/the-albuquerque-stripper.16040/page-12#post-256566

From my parts cataloging, with MC's --

FR3Z-2140-A performance pack manual 3 nip
FR3Z-2140-B performance pack auto 2 nip
FR3Z-2140-C base GT and Shelby GT350
FR3Z-2140-D auto 2 nipple

for BB's, they also have 4 -- and leaving my feelings out of this, these words come directly from Ford themselves. I'd hate to slander their good name.

JR3Z-2005-B Mustang. 5.0, all.
JR3Z-2005-C Mustang. 2.3L, performance brakes. Brembo Package. Exc. High Performance Brakes. Performance Package.
JR3Z-2005-D Mustang. Brembo Package. High Performance Brakes. 2.3l. High series police pkg. Without performance.
JR3Z-2005-Z Mustang. 2.3L, high series brakes. Brembo Package. High Performance Brakes. High series police pkg. With performance.

I had started with the B, and swapped in the Z. Objectively, the brake booster shouldn't matter, but as I could finally stop, and very, very hard, at least for my scenario/setup, it worked. Perhaps I had inherited a busted one with my salvage, but the typical problems with vacuum and car idling/stalling issues on clutching suggest otherwise. I have the old one if somebody wants to bust it open :)

My reason for wanting to upgrade is just to further complete the retrofit. The base GT comes with some 245/45/19 combo, and the PP2 comes with 305/30/19 Cup 2's. I know I run much better tire than the Cup2 now, but they also have different as built codes, which would tend to have me believe that they have a slightly different programming on it with more tolerance for stopping and G's, as they assume somebody is much more likely to track their PP2 than a base GT. The other thing of note is that the caliper pistons on the PP calipers are 36/36/36, compared to the GT350's 36/34/32. That might not seem like a big difference, but it's enough that Ford added two SKU specifically for performance packs, and strangely enough, don't give it to the GT350, who continues to share it with the base GT.

I think we could all agree that the FP350s would and should be differently calibrated, but now knowing the differences in the MC's, I'm also now more confused with how it'd interact with the MC being changed slightly, and I'm going to assume the FP350s brakes are also the 36/34/32 pistons as well.

As usual, I'm more confused AFTER writing a post, but I'm also down to give anything a shot, it's just flashing a code. If somebody can give me a FP350s VIN or As Built coding for the ABS module, I'll be willing to give it a shot.
 
1,011
947
In the V6L
I'm curious to find out for sure. You can put on the 6 piston upgraded calipers, rotors, and pads, and it will work. Kinda. I'd still fade halfway through a session, but ACS is probably the most abusive braking track I know of.

As for what's the same ... eh? -- https://trackmustangsonline.com/threads/the-albuquerque-stripper.16040/page-12#post-256566

From my parts cataloging, with MC's --

FR3Z-2140-A performance pack manual 3 nip
FR3Z-2140-B performance pack auto 2 nip
FR3Z-2140-C base GT and Shelby GT350
FR3Z-2140-D auto 2 nipple

for BB's, they also have 4 -- and leaving my feelings out of this, these words come directly from Ford themselves. I'd hate to slander their good name.

JR3Z-2005-B Mustang. 5.0, all.
JR3Z-2005-C Mustang. 2.3L, performance brakes. Brembo Package. Exc. High Performance Brakes. Performance Package.
JR3Z-2005-D Mustang. Brembo Package. High Performance Brakes. 2.3l. High series police pkg. Without performance.
JR3Z-2005-Z Mustang. 2.3L, high series brakes. Brembo Package. High Performance Brakes. High series police pkg. With performance.

I had started with the B, and swapped in the Z. Objectively, the brake booster shouldn't matter, but as I could finally stop, and very, very hard, at least for my scenario/setup, it worked. Perhaps I had inherited a busted one with my salvage, but the typical problems with vacuum and car idling/stalling issues on clutching suggest otherwise. I have the old one if somebody wants to bust it open :)

My reason for wanting to upgrade is just to further complete the retrofit. The base GT comes with some 245/45/19 combo, and the PP2 comes with 305/30/19 Cup 2's. I know I run much better tire than the Cup2 now, but they also have different as built codes, which would tend to have me believe that they have a slightly different programming on it with more tolerance for stopping and G's, as they assume somebody is much more likely to track their PP2 than a base GT. The other thing of note is that the caliper pistons on the PP calipers are 36/36/36, compared to the GT350's 36/34/32. That might not seem like a big difference, but it's enough that Ford added two SKU specifically for performance packs, and strangely enough, don't give it to the GT350, who continues to share it with the base GT.

I think we could all agree that the FP350s would and should be differently calibrated, but now knowing the differences in the MC's, I'm also now more confused with how it'd interact with the MC being changed slightly, and I'm going to assume the FP350s brakes are also the 36/34/32 pistons as well.

As usual, I'm more confused AFTER writing a post, but I'm also down to give anything a shot, it's just flashing a code. If somebody can give me a FP350s VIN or As Built coding for the ABS module, I'll be willing to give it a shot.
I assume you know all this already, but if not, then start with the FP350S bill of material here: https://performanceparts.ford.com/Download/PDFS/M-FP500-FP350S_Web_BOM_7-11-2018.pdf

The front calipers are Essex PN 13.05.20033/32 which translate to AP Racing Calipers CP9660-3S4L/2S4L with Piston Sizes - 27.0, 31.8 and 38.1mm. Total piston area 50.1square mm. Booster/MC assembly is FR3V-2B195-PD.
 

PaddyPrix

If breakin' parts is cool, consider me Miles Davis
424
552
Exp. Type
Time Attack
Exp. Level
Under 3 Years
San Diego
I assume you know all this already, but if not, then start with the FP350S bill of material here: https://performanceparts.ford.com/Download/PDFS/M-FP500-FP350S_Web_BOM_7-11-2018.pdf

The front calipers are Essex PN 13.05.20033/32 which translate to AP Racing Calipers CP9660-3S4L/2S4L with Piston Sizes - 27.0, 31.8 and 38.1mm. Total piston area 50.1square mm. Booster/MC assembly is FR3V-2B195-PD.
I appreciate the part numberings, I'll see if I can't figure a way to pull the as built with that or figure out their pattern, if there is one.

Seeing Essex there also gives my the feeling that those parts are worth more than my whole car :)
 
1,011
947
In the V6L
...If somebody can give me a FP350s VIN or As Built coding for the ABS module, I'll be willing to give it a shot.
Well, the real race car FP350S that isn't manufactured by Ford doesn't have a VIN, so that won't help. The Bill of Material shows an FP ABS module, and you might be able to buy one from them directly. Of course, the rest of the car might go bonkers if it doesn't have an ABS module that plays nice with the ECU and the BCM, etc. As far as as built coding is concerned, I've tried it - I wanted to flip mine from GT350 ABS to GT350R - a single bit change - and it declined with vigor. Forscan simply said it couldn't be done.
 
81
49
Exp. Type
Autocross
Exp. Level
20+ Years
So Cal
OK, I was a bit confused there, because I knew the GT4 car has the Bosch system. I've seen the FP controller in the book for a while, but when I called to actually buy one, they couldn't/wouldn't sell it. They had the S197 version ready to go, but not the one for the S550 chassis. That's why I went down the road of getting one from a higher model.
 

PaddyPrix

If breakin' parts is cool, consider me Miles Davis
424
552
Exp. Type
Time Attack
Exp. Level
Under 3 Years
San Diego
As far as as built coding is concerned, I've tried it - I wanted to flip mine from GT350 ABS to GT350R - a single bit change - and it declined with vigor. Forscan simply said it couldn't be done.
Dang 😔
 
81
49
Exp. Type
Autocross
Exp. Level
20+ Years
So Cal
Complete side note. The owners manual on that FP350S is the real deal. If someone wants a track alignment numbers, there's a pretty good start. Also, they actually have damper curves included.
 
62
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Exp. Type
HPDE
Exp. Level
Under 3 Years
Cantley
whoever wrote that article made discovery that SC2s brake better than PS4S....
I seem to remember reading PS4S brake slightly better than SC2. And that SC2 was better at lateral grip. You are saying SC2 was proven better at both?
 
62
34
Exp. Type
HPDE
Exp. Level
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Cantley
On the GT line I thought all the BB and MC are the same?
In Terry Fair's build thread 2018 base GT he actually measured the MC bore on the base and PP version and there is a difference. I decided to track with 6 piston and base MC and it sucked. Brakes did not fade like my base brake setup, but pedal feel and front/rear distribution of braking power was very unsettling to me. I can't live with that so I started this thread to see if there was also a software component to change, or if simply changing booster and MC with base GT abs module is "good enough" for HPDE.
 
81
49
Exp. Type
Autocross
Exp. Level
20+ Years
So Cal
If you run the numbers on any of the caliper packages, you find they all have very similar (within a couple percent) hydraulic ratios. The master size will change pedal effort, but it should have no influence on bias. Are you certain the system was completely bled?
 
496
318
sfo
Considering there are 4 different Ford part numbers for MC and 4 different part numbers for BB, I suspect the Cheap beancounters at Ford would not have allowed 4 different versions of the same thing without good reason.
 
81
49
Exp. Type
Autocross
Exp. Level
20+ Years
So Cal
It's a hydraulic ratio, not black magic. While the Ford engineers no doubt had reasons for their actions, those reasons will, in fact, be subject to certain physical laws. Once we understand that bit, then we can probably sort out why there are 4 different master cylinders for 3 brake systems which all have very similar caliper piston area (although different disc diameters). No doubt those master cylinders are shared among platforms, so it appears to me as if they use MC bore sizes to influence pedal feel. I'd have to actually know the bore sizes to make that statement with greater certainty, but it's a logical explanation.
 

PaddyPrix

If breakin' parts is cool, consider me Miles Davis
424
552
Exp. Type
Time Attack
Exp. Level
Under 3 Years
San Diego
It's a hydraulic ratio, not black magic. While the Ford engineers no doubt had reasons for their actions, those reasons will, in fact, be subject to certain physical laws. Once we understand that bit, then we can probably sort out why there are 4 different master cylinders for 3 brake systems which all have very similar caliper piston area (although different disc diameters). No doubt those master cylinders are shared among platforms, so it appears to me as if they use MC bore sizes to influence pedal feel. I'd have to actually know the bore sizes to make that statement with greater certainty, but it's a logical explanation.
inner bore is 22mm vs 23.5mm, pedal feel is the same, brake modulation is the same, stopping ability greatly increased. I doubt they'd do anything between with the pp's difference being nipple count for auto/manual. PP brake pistons are 36/36/36, GT350 are 38/36/34, and base GT s550 (if they're the same as the previous generation Brembo) 44/40
 
Last edited:
496
318
sfo
It's a hydraulic ratio, not black magic. While the Ford engineers no doubt had reasons for their actions, those reasons will, in fact, be subject to certain physical laws. Once we understand that bit, then we can probably sort out why there are 4 different master cylinders for 3 brake systems which all have very similar caliper piston area (although different disc diameters). No doubt those master cylinders are shared among platforms, so it appears to me as if they use MC bore sizes to influence pedal feel. I'd have to actually know the bore sizes to make that statement with greater certainty, but it's a logical explanation.

Maybe it is less about feel and more about the right performance setup for each model in the line? Many things influence pedal feel and performance. Tire capability influences the package as an example and from bse GT to GT350 the wheel size is 8" to 11" making for quite a difference in rubber on the road. That alone can alter the parts in the package. Then there is math and other small details that aren't in the calculation that make a real world difference that only can be finalized in real world testing.
 
81
49
Exp. Type
Autocross
Exp. Level
20+ Years
So Cal
inner bore is 22mm vs 23.5mm, pedal feel is the same, brake modulation is the same, stopping ability greatly increased. I doubt they'd do anything between with the pp's difference being nipple count for auto/manual. PP brake pistons are 36/36/36, GT350 are 38/36/34, and base GT s550 (if they're the same as the previous generation Brembo) 44/40

TL;DR: Master cylinder piston area to caliper piston area controls pedal effort, height and feel. If we keep all else the same, though, it doesn't influence actual braking capacity or bias.
--------------------------------------------------------------------------------------------------------------------------

Let's look at these two master cylinders, 23.5mm vs 22.0mm:

That's a 14% difference on the master cylinder piston area, which means a 14% difference in braking force for a given pedal pressure. It also means a greater force change with your foot on the pedal to modulate.
  • Pedal pressure for a given amount of braking would be 14% higher for the 23.5mm master than the 22mm one.
  • Pedal *travel* will be longer with the smaller master. As long as nothing gets into a bad situation geometrically or with respect to travel (i.e. it doesn't bottom out or put the pedal in an over center position), it will not affect performance.
  • Larger MC's (with greater effort) generally get better comments concerning modulation
  • Larger MC's will have a higher and firmer pedal
  • If the master is too large, then the driver might struggle to reach an appropriate peak pressure or may just have to use too much muscle to effectively drive.
  • A standard automotive master (as opposed to dual masters on a race car) doesn't change F/R bias.
  • The ABS controller regulates proportioning/brake bias.
  • The brake booster has a big effect on pedal feel, but it doesn't sound like anyone is changing boosters.
  • The staggered piston sizing of the Shelby is to reduce taper wear on the pad. Not having it on the PP brakes is just an insult. Calipers with staggered pistons are no different cost than with uniform piston sizes. It's just an effort to give the Shelby a talking point by tanking the PP.
  • Pad compounds can have a much bigger effect on max pedal pressure and modulation than MC sizing.
  • A big problem when testing master cylinders is getting an effective bleed. It's damned tough to beat the factory bleed, so don't crack the lines unless you have to. If you changed a master cylinder and found bias or performance differences, then it may very well be a bad bleed as opposed to a problem with the master sizing.
 

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