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Huge brake upgrade for S197 chassis

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You can go a long way by just making sure you have brake ducts and a good set of pads..... I used pagid RS29 pads on the street and track with great results. Actually you can outbrake a lot of cars with that combo.... Only noticed a need for more braking then my OEM brembos with race pads, on tracks with more then 130mph straights and longer then 15min flat out.
I do have brake cooling ducting currently installed. I’m running 1521 carbotechs as a street pad and was never really thrilled with what I felt was low initial bite. Otherwise haven’t had an issue with them. I was thinking the larger GT500 brakes would get me some more initial grab on the street due to surface area without having to run a more aggressive pad.
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
I do have brake cooling ducting currently installed. I’m running 1521 carbotechs as a street pad and was never really thrilled with what I felt was low initial bite. Otherwise haven’t had an issue with them. I was thinking the larger GT500 brakes would get me some more initial grab on the street due to surface area without having to run a more aggressive pad.
Pads will give you all the bite you want..... one of the biggest upgrades you can do for track. Look at Randy Pobsts complaints about the 15" gt500 brake setup..... thats pads...not disc size.

Sent from my SM-G900M using Tapatalk
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Pads will give you all the bite you want..... one of the biggest upgrades you can do for track. Look at Randy Pobsts complaints about the 15" gt500 brake setup..... thats pads...not disc size.

Sent from my SM-G900M using Tapatalk
I saw a Vorshlag video about how the USA S550 14" setup has a master cylinder thats too small for the 15" brembo setup... lucky for us the S550's that came to Chile had 14" brembos labeled calipers and so far zero drama on the track...... nothing like the dramas the Vorshlag saw.

Sent from my SM-G900M using Tapatalk
 
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Is the S550 PP master cylinder needed? @captdistraction , I think it is probably a matter of preference with regard to pedal throw and firmness. The S197 master has a 1.0625 ( 1 1/16") bore. The S550 has a 1.125 (1 1/8") bore.

The S550 front calipers have a larger piston area and volume compared to the S197 Brembo front brakes. But, no one discussed that the S550 rear calipers have a are smaller piston area than the S197 rears.

The problem with the S550 master is that it doesn't just have a bigger bore than the S197, it also has a different push rod length / depth of 1.79" vs the S197 1.1".

I am not sure if you can simply bolt the S550 master up to an S197 booster. I also don't know what kinds of problems you would introduce by attempting to retrofit the entire S550 master and booster to an S197. If you were to attempt this, you would need to make sure the push rod length, pedal ratio, and pedal bell crank geometry all were correct other wise you could still have issues with a soft pedal, low pedal, hard pedal, etcetera.

The simplest solution would be to contact whoever originally made the S197 master and ask if they have an identical master is a slightly larger bore.

Finally, I know it sounds dumb, but the S197 firewall flexes a under braking. You can easily see the master and booster move when someone steps on the brake pedal. This flex equals a longer pedal throw, which is a small amount at the pedal pivot point, but grows larger based on the length of your pedal. Why do I bring this up? Because before I went through all the trouble of fabricating another master cylinder and booster combination, I would install the Blowfish master cylinder support brace. The brace will eliminate this flex and additional pedal travel. It might be enough that you are happy with the original S197 master cylinder.
 
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Is the S550 PP master cylinder needed? @captdistraction , I think it is probably a matter of preference with regard to pedal throw and firmness. The S197 master has a 1.0625 ( 1 1/16") bore. The S550 has a 1.125 (1 1/8") bore.

Thank you very much for this information, it will save me a lot of leg work. I think I agree with you, that 0.06" piston difference is not enough to worry about.

Again, thank you sir.....
 
@2012-Boss
What would the braking characteristics of a S197 with 4 piston brembo's and then upgrades to S500 6 piston brembo's? ie; firmer or softer pedal with shorter or longer travel.

Longer travel. I have done this upgrade, the additional travel is barely perceptible. It in no way inhibits my ability to heal-toe rev match. In fact, the additional travel may help modulation. It's all about preference. At the end of the day, for me it provides great peace of mind knowing you have additional brake capacity and more robust hardware for not a lot of investment. Well worth it IMO.

I would also submit, Ford Racing offers this brake kit as an upgrade for S550s with the 1-1/16" master cylinder (All non Brembo cars):

https://performanceparts.ford.com/part/M-2300-V

I've been hearing a lot of chatter lately on this topic but I trust Ford Racing's engineers over opinions on the interwebs.
 
...I've been hearing a lot of chatter lately on this topic but I trust Ford Racing's engineers over opinions on the interwebs.

Having dealt with "Ford Racing" and with Ford production engineers, I trust their production engineers, but not always what goes into their "Racing" catalog.

And we don't know for sure that the master cylinder will fix it. We are going to test it soon and see.
 
@modernbeat , Look forward to hearing the results.


That said I have been following this thread for a while now and I have read nothing but positive results from this swap. This master cylinder uncertainty isn't going to stop me from doing the swap.
 
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I think, at least with regard to the S197, is an option on master cylinder size would accommodate a driver's preference in how the brake pedal feels. . Most people do not mind the additional travel that results from the S550 caliper swap, but occasionally someone like captdistraction does. That is where preference comes into play. Some drivers like a higher, firmer pedal. Some like a longer more progressive pedal.

I am really interested in Vorshlag's fitting of the 6 piston calipers on their new S550 and the test results.
 

captdistraction

GrumpyRacer
1,954
1,698
Phoenix, Az
The knockback is an issue for sure. I need to redo my rotors to be fully floating (they're semi-bolted together now, floating pins on every other fastener location) and see if that helps, but after a few corners, its hard to defeat all that mass.

I've been working on ankle flexibility to see if I can train around the long pedal issues I have, but I'm definitely in the camp of wanting the firmer shorter pedal (the longer one DOES give better modulation control, but if you have good muscle control in your feet, its not a huge difference in control of the vehicle during a race).

My interim fix is to put an autoblip in the car. Not ideal but less risk than altering hydraulics. I also run the MC brace, but it definitely didn't help much in my application.

Another thing to watch for in extreme duty is pad taper. We're monitoring that on my racecar but keep an eye on the pads. So far I'm getting good life out of a box of pads but if I can keep taper under control, I'd start to say great life.
 
@2012-Boss
What would the braking characteristics of a S197 with 4 piston brembo's and then upgrades to S500 6 piston brembo's? ie; firmer or softer pedal with shorter or longer travel.

The pedal is slightly longer to engage the ABS but it has a good solid feel from lmost the very beginning of pressing the pedal. Just a little of take up is required.
 
I started giving the pedal a light tap with my left foot while going down the straights to re seat the pads. Helped a bunch.

I'm still eyeing real brakes. But I have six months to ponder it while I'm out of the country.

This is the first many of have heard about Caliper Knock and this set up. What is causing this issue for you? Is it the two piece rotors? Pad wear? I don't drive nearly as hard as the majority of you but this isn't an issue I've encountered.

Is your ride a full on race car now. Please don't mind the questions, just wondering how you reached the limit of this set up and when we can expect the same.
 
This is the first many of have heard about Caliper Knock and this set up. What is causing this issue for you? Is it the two piece rotors? Pad wear? I don't drive nearly as hard as the majority of you but this isn't an issue I've encountered.

Is your ride a full on race car now. Please don't mind the questions, just wondering how you reached the limit of this set up and when we can expect the same.

One piece GT-500 rotors on my car. Floating two piece is actually a counter to knockback. Which is why captdistraction is moving that direction.

I drive the car on the street as well, but the issue is only really present on the track. 315 section Cup 2 tires at all four corners for the track, regular old summer performance tires on the street. Something (likely multiple things combined) in there is flexing through the corners. It never seemed as bad as Terry Fair experienced, but I'm not a licensed competitor either.
 

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