Brake upgrade

[me32]

Gladly.

Well, first I recommend going through some of articles from StopTech, they are excellent reads.
Resource Library

Here is a good one to start with https://www.apcautotech.com/getmedi...e-Systems-and-Upgrade-Selections_8-2018_1.pdf

Now, StopTech argues, and I agree with this, its important to maintain balance when it comes to brakes. Which means you don't want to increase stopping force only in the front or the back. So for me I wanted the brakes to last longer on the track and the 13/14 brakes kit do just that by increasing the rotor diameter and the pads surface area without increasing stopping force.

How do I know all of this, from one of the StopTech articles, they give you the formula for the torque generated at the wheel and its basically a multiplication of 1.fluid pressure 2.caliper piston area 3.friction coefficient from the pad 4.diameter of brake rotor.

After digging around, I found the piston area of the Brembo 4 pot to be 4.3 in^2, and the 13/14 Brembo 6 pot is 4.26 in^2. If you do the calculation you'll find the 13/14 is only %6 more torque, its probably less because the whole system is not %100 efficient. Loss in pressure or deflection of the caliper will effect the final results.

The 15+ caliper and the GT350 are 4.73 and 4.75 in^2 respectively and they are IMO too much for our cars, unless one can balance the rear with the fronts I wouldn't touch them. Besides, based on hydraulics you'll see that the larger piston area would make the brake pedal travels longer and probably feel softer. But for the 13/14, the smaller area will make the pedal firmer, but again I don't think it will be noticeable.

I dont see how your post proves anything about not improving braking power.

Also you do realize that the 15+ 6piston uses basically the same size rear as the 13/14 gt500.

Yes brakes need a balance. But take the gt350 brakes for example. They have extremely well set up brakes over the performance pack 6piston setup on the gt. Care to explain that?

Imo there is no such thing as too much brakes.

 

[Black Cobra '99]

I dont see how your post proves anything about not improving braking power.

Also you do realize that the 15+ 6piston uses basically the same size rear as the 13/14 gt500.

Yes brakes need a balance. But take the gt350 brakes for example. They have extremely well set up brakes over the performance pack 6piston setup on the gt. Care to explain that?

Imo there is no such thing as too much brakes.

Torque = Pressure * 2 * Piston area * coefficient of friction * rotor dimeter

You increased the rotor dimeter from 14" to 15", but you also decreased piston area from 4.3 to 4.26. So, with everything else the same you end up with only a %6 increase in torque going from the 4 pot to the 6 pot.

One more thing to note about balance is weight transfer, brakes system are designed around how much weight transfers from front to rear when braking and so that additional weight needs to be accounted for.

I'm not familiar with rear brakes on the 15 but I don't see why this is important to this discussion. The 15+ and GT350 front brakes are very similar, and in the case of the GT350 the real effort was put into making the whole front end rigid enough to get a better braking feel, for example the caliper on the GT350 has a bridge as part of the cast while the 15 has a steel bolt.

Yes, there is such a thing as too much brake. The evidence to that is find me a car that cannot lock its wheel under heavy breaking, and I'm talking about sports cars with high gripping tires. Again, StopTech covers much of this and they know what they are doing.

 

[Black Cobra '99]

I should also add, there is no point in comparing the s550 to the s197 as a whole because a lot of things changed like master cylinder, brake booster, weight, weight distribution, weight transfer, etc... and there is no way to know that all of those were strictly for performance.

The more reasonable approach is to compare one component to the other on the same car, that way we know everything else is the same and we change one thing and we can get a reliable comparison.

 

[me32]

Torque = Pressure * 2 * Piston area * coefficient of friction * rotor dimeter

You increased the rotor dimeter from 14" to 15", but you also decreased piston area from 4.3 to 4.26. So, with everything else the same you end up with only a %6 increase in torque going from the 4 pot to the 6 pot.

One more thing to note about balance is weight transfer, brakes system are designed around how much weight transfers from front to rear when braking and so that additional weight needs to be accounted for.

I'm not familiar with rear brakes on the 15 but I don't see why this is important to this discussion. The 15+ and GT350 front brakes are very similar, and in the case of the GT350 the real effort was put into making the whole front end rigid enough to get a better braking feel, for example the caliper on the GT350 has a bridge as part of the cast while the 15 has a steel bolt.

Yes, there is such a thing as too much brake. The evidence to that is find me a car that cannot lock its wheel under heavy breaking, and I'm talking about sports cars with high gripping tires. Again, StopTech covers much of this and they know what they are doing.

You do not want a car to lock its brakes. You want them to stop the car as fast as possible without locking them. Once again ive never seen a vehicle with too much braking. Show me a car that has too much brake?

Also stoptech is in the business to sell brakes so there information will be biased in a way to sell there kits. Your information is mostly from one source and not personal experience.

My personal experience with brake upgrades says otherwise.

 

[Black Cobra '99]

You do not want a car to lock its brakes. You want them to stop the car as fast as possible without locking them. Once again ive never seen a vehicle with too much braking. Show me a car that has too much brake?

Also stoptech is in the business to sell brakes so there information will be biased in a way to sell there kits. Your information is mostly from one source and not personal experience.

My personal experience with brake upgrades says otherwise.

I tried to explain the physics behind the braking system and what it means to change certain components in it, if you can't trust what engineers do than there is no point in discussing this any further.

EDIT: The numbers I shared were what ford changed for the 13/14 and has nothing to do with StopTech.
I'd like to know what you did to your brakes and what changes did you see.

 

[Black Cobra '99]

You do not want a car to lock its brakes. You want them to stop the car as fast as possible without locking them. Once again ive never seen a vehicle with too much braking. Show me a car that has too much brake?

Exactly my point. Almost every car can lock up its brakes with the stock braking system, so why would you want even more brakes? Your maximum braking is limited by the tires, and the braking system can always overcome the tires max grip and lock up, thats why you don't need more brakes.

 

[Imatk]

So here's my experience FWIW.

I "upgraded" the brakes on mine to the exact one OP mentioned. I actually found a pair of takeoffs on Ebay for 700 bucks.

All in I think I spent about 900 bucks on the setup. I also did the rear brackets and rotors a little later which was another few hundred.

If I had to do it again? I'd stick with the stock brakes.

Why?
The 13/14 are heavier both calipers and rotors, I bought a two-piece setup which was much lighter but cost me quite a bit to try and combat that

Girodisc Front 2pc Floating Rotors for 13-14 GT500


And the car stops well, but for my needs it stopped just as well before. I literally felt no difference.

I wish I could say I DID but I didn't.

The one thing I DID feel a difference in... well two things.

1. Brake pad
2. Tires

I swapped the OEM pads for Carbotech Cermaic pads mostly because the dusting was insane with the OEM pads.

The Ceramic pads do not stop as well as the OEM. Probably because they aren't as soft... but I have no idea.

But no more black dust all over so I'm happy.

On the track... maybe the larger rotor would make a difference but I don't track my car so it was literally a complete waste of money except for the fact that they look cool.

But again... had I to do it over I wouldn't pay over 2k to have brakes that look cool... my pockets aren't that deep

 

[MastaAce03]

So here's my experience FWIW.

I "upgraded" the brakes on mine to the exact one OP mentioned. I actually found a pair of takeoffs on Ebay for 700 bucks.

All in I think I spent about 900 bucks on the setup. I also did the rear brackets and rotors a little later which was another few hundred.

If I had to do it again? I'd stick with the stock brakes.

Why?
The 13/14 are heavier both calipers and rotors, I bought a two-piece setup which was much lighter but cost me quite a bit to try and combat that

Girodisc Front 2pc Floating Rotors for 13-14 GT500


And the car stops well, but for my needs it stopped just as well before. I literally felt no difference.

I wish I could say I DID but I didn't.

The one thing I DID feel a difference in... well two things.

1. Brake pad
2. Tires

I swapped the OEM pads for Carbotech Cermaic pads mostly because the dusting was insane with the OEM pads.

The Ceramic pads do not stop as well as the OEM. Probably because they aren't as soft... but I have no idea.

But no more black dust all over so I'm happy.

On the track... maybe the larger rotor would make a difference but I don't track my car so it was literally a complete waste of money except for the fact that they look cool.

But again... had I to do it over I wouldn't pay over 2k to have brakes that look cool... my pockets aren't that deep

Thanks for the update. Reviews like this are extremely helpful for people on the fence deciding which way to go.


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[Black Cobra '99]

So here's my experience FWIW.

I "upgraded" the brakes on mine to the exact one OP mentioned. I actually found a pair of takeoffs on Ebay for 700 bucks.

All in I think I spent about 900 bucks on the setup. I also did the rear brackets and rotors a little later which was another few hundred.

If I had to do it again? I'd stick with the stock brakes.

Why?
The 13/14 are heavier both calipers and rotors, I bought a two-piece setup which was much lighter but cost me quite a bit to try and combat that

Girodisc Front 2pc Floating Rotors for 13-14 GT500


And the car stops well, but for my needs it stopped just as well before. I literally felt no difference.

I wish I could say I DID but I didn't.

The one thing I DID feel a difference in... well two things.

1. Brake pad
2. Tires

I swapped the OEM pads for Carbotech Cermaic pads mostly because the dusting was insane with the OEM pads.

The Ceramic pads do not stop as well as the OEM. Probably because they aren't as soft... but I have no idea.

But no more black dust all over so I'm happy.

On the track... maybe the larger rotor would make a difference but I don't track my car so it was literally a complete waste of money except for the fact that they look cool.

But again... had I to do it over I wouldn't pay over 2k to have brakes that look cool... my pockets aren't that deep

Tires are the limiting factor when it comes to maximum braking possible, and when comparing the 6 pot to the 4, brake pads are the only thing that significantly change the braking power according to the equation I posted before. So there you go.

Thank you for sharing an unbiased review Imtak. A lot of the time spending so much money on "upgrades" make people believe it made a difference when it actually didn't, it may even make the car worse.

 

[Totalpkg]

So here's my experience FWIW.

I "upgraded" the brakes on mine to the exact one OP mentioned. I actually found a pair of takeoffs on Ebay for 700 bucks.

All in I think I spent about 900 bucks on the setup. I also did the rear brackets and rotors a little later which was another few hundred.

If I had to do it again? I'd stick with the stock brakes.

Why?
The 13/14 are heavier both calipers and rotors, I bought a two-piece setup which was much lighter but cost me quite a bit to try and combat that

Girodisc Front 2pc Floating Rotors for 13-14 GT500


And the car stops well, but for my needs it stopped just as well before. I literally felt no difference.

I wish I could say I DID but I didn't.

The one thing I DID feel a difference in... well two things.

1. Brake pad
2. Tires

I swapped the OEM pads for Carbotech Cermaic pads mostly because the dusting was insane with the OEM pads.

The Ceramic pads do not stop as well as the OEM. Probably because they aren't as soft... but I have no idea.

But no more black dust all over so I'm happy.

On the track... maybe the larger rotor would make a difference but I don't track my car so it was literally a complete waste of money except for the fact that they look cool.

But again... had I to do it over I wouldn't pay over 2k to have brakes that look cool... my pockets aren't that deep

Thats why I dont understand why people go to the 2013/2014 calipers. The pad size isnt that much different. The S550 on the other hand...

2015 PP pads vs 2013/2014 pads

4 piston GT500 vs S550 PP pads:

 

[Imatk]

Thats why I dont understand why people go to the 2013/2014 calipers. The pad size isnt that much different. The S550 on the other hand...

2015 PP pads vs 2013/2014 pads

View attachment 1568083


4 piston GT500 vs S550 PP pads:

View attachment 1568092

Well for me those weren't out yet... I put them on in 2014.

 

[Totalpkg]

Well for me those weren't out yet... I put them on in 2014.

Ahh...makes sense... I was in your shoes wanting the bigger rotors and calipers, I could never find a good deal on 13/14 6 piston calipers and rotors, then I saw that forum post about the S550 calipers. The GT350 calipers use even bigger rotors. Not sure about pad size...

I wish we had a 4 piston fixed rear caliper option that was cost effective...

 

[Catmonkey]

Piston diameters also have a lot to do with how effective the caliper is and someone posted this data in one of these threads. I'm not sure the S550 has any real benefit based on piston sizes. If I can find the info, I'll post a link.

 

[Totalpkg]

Piston diameters also have a lot to do with how effective the caliper is and someone posted this data in one of these threads. I'm not sure the S550 has any real benefit based on piston sizes. If I can find the info, I'll post a link.

Found this on a Google search on the s197forum.com :

"I don't think bias is an issue at all; see the volumes below. The "base" GT piston area is actually the largest of the bunch. The other setups make up for lost Clamping Force with an increase in Effective Diameter, which yields an increase in Wheel Torque of 9% with the 13/14 GT500 caliper and 8% with the 2015 GT PP caliper.

Piston Diameters (mm)
05-14 GT: 43, 43
07-12 GT500: 44, 40
13-14 GT500: 38, 34, 30
2015 GT PP: 34, 34, 34

Piston Diameters (inches)
05-14 GT: 1.69, 1.69
07-12 GT500: 1.73, 1.57
13-14 GT500: 1.50, 1.34, 1.18
2015 GT PP: 1.34, 1.34, 1.34 "

 

[03 DSG Snake]

@ac427cobra Bruce would be the expert on both of those calipers.

 

[03 DSG Snake]

So here's my experience FWIW.

I "upgraded" the brakes on mine to the exact one OP mentioned. I actually found a pair of takeoffs on Ebay for 700 bucks.

All in I think I spent about 900 bucks on the setup. I also did the rear brackets and rotors a little later which was another few hundred.

If I had to do it again? I'd stick with the stock brakes.

Why?
The 13/14 are heavier both calipers and rotors, I bought a two-piece setup which was much lighter but cost me quite a bit to try and combat that

Girodisc Front 2pc Floating Rotors for 13-14 GT500


And the car stops well, but for my needs it stopped just as well before. I literally felt no difference.

I wish I could say I DID but I didn't.

The one thing I DID feel a difference in... well two things.

1. Brake pad
2. Tires

I swapped the OEM pads for Carbotech Cermaic pads mostly because the dusting was insane with the OEM pads.

The Ceramic pads do not stop as well as the OEM. Probably because they aren't as soft... but I have no idea.

But no more black dust all over so I'm happy.

On the track... maybe the larger rotor would make a difference but I don't track my car so it was literally a complete waste of money except for the fact that they look cool.

But again... had I to do it over I wouldn't pay over 2k to have brakes that look cool... my pockets aren't that deep

Do you have any photos of those 15” Giros?

 

[Imatk]

Do you have any photos of those 15” Giros?

I found this thread I posted when I put them on. Definite weight savings

https://www.svtperformance.com/threads/two-piece-girodisc-rotors.1131490/

 

[merkyworks]

The larger pad size of 2015+ GT 6 piston calipers will help with attrition but the main reason to use them over 2013-2014 GT500 6 piston calipers is brake pad selection. WAY more aftermarket brake pad options for 2015+ GT 6 piston calipers Vs 2013-2014 GT500 6 piston calipers.

As for running 4 piston rear calipers as far as I know no one makes a floating 4 piston caliper, they are only offered in fixed mounts. Solid axel cars tend to have issue with fixed mounted rear calipers and pad knock back, which is not ideal in any braking situation.