S550 Peformance Package (6-Piston Brembo) on S197

[2Fass240us]

I picked up a set of S550 Performance Package front brakes late last year and am finally getting around to test-fitting them. While the 6-piston setup from the '13/'14 GT500 seems to have some tech, the S550 PP one does not. If this has been covered in another thread, please LMK and I can move the content there.

I took measurements on the S550 rotor using a dial caliper for all but the diameter, and used Centric data from Rock Auto on the GT500 one. I will likely buy a GT500 rotor to confirm measurements and do a physical test-fit.

Biggest differences:

• The GT500 rotor is 1.26" thick versus the S500 one being 1.34"
• The effective hat offset for the GT500 rotor is 0.232"* versus the S550 at 0.868"

*Need to confirm after buying one

Test-fit on S197 spindle with full S550 setup:

Creating offset using spacers between the spindle and rotor, to simulate estimated GT500 offset:

This is close but I still need the GT500 rotor to confirm:

 

[weather man]

Good shit, keep going.

 

[2Fass240us]

Finding a '13/'14 GT500 rotor locally is proving more difficult than I previously thought. Struck out at AutoZone and Advance. Trying Napa next.

 

[2Fass240us]

Finding a '13/'14 GT500 rotor locally is proving more difficult than I previously thought. Struck out at AutoZone and Advance. Trying Napa next.

also a fail

O'Reilly's to the o'rescue. Rotors will be in the store by 2pm tomorrow.

 

[2Fass240us]

Confirmed that 2013/2014 GT500 rotors are a perfect fit, leading me to believe the calipers are the same between the aforementioned and the 2015 PP ones.

 

[NickD87]

There is a thread on here discussing and test fitting the 4 piston 15+ calipers on the s197 and the result was the caliper needed to be shimmed 9/16th and the pads were not making the same contact. The different offset seems to effect caliper mounting not just rotor.

Are you finding different results with the 6 pistons?

 

[2Fass240us]

There is a thread on here discussing and test fitting the 4 piston 15+ calipers on the s197 and the result was the caliper needed to be shimmed 9/16th and the pads were not making the same contact. The different offset seems to effect caliper mounting not just rotor.

Are you finding different results with the 6 pistons?

The offset is nearly the same but it's in the wrong direction and thus can't be shimmed (see the 4th picture in the 1st post).

...The different offset seems to effect caliper mounting not just rotor.

Not following you...it's all related.

 

[v6tungsten]

There is a thread on here discussing and test fitting the 4 piston 15+ calipers on the s197 and the result was the caliper needed to be shimmed 9/16th and the pads were not making the same contact. The different offset seems to effect caliper mounting not just rotor.

Are you finding different results with the 6 pistons?

I test fit the 2015 4 pistons on a S197 and there wasnt a 9/16 shimming needed. My problem is my wheel wouldnt clear the 2015 calipers.

No shimming was required but it was advised to center the caliper on the rotor...maybe 1/16" to 1/8" max. and that would push the caliper farther out hitting my 20" wheels

Pictures of my 18" that cleared and shimming that would need to be done

 

[2Fass240us]

Confirmed that 2013/2014 GT500 rotors are a perfect fit

I spent a couple of hours in the garage last night taking measurements and pictures. Here are some of the pictures:

Test-fitting the 18" Forgestar CF5, one of the only wheels known to clear this package.

Visual on the offset difference between the two rotors:

 

[v6tungsten]

Are you fitting 2015 rotor or 2007-9 gt500 rotors

 

[2Fass240us]

Are you fitting 2015 rotor or 2007-9 gt500 rotors

I started with the 15" 2015 S550 Performance Package rotors. Knowing beforehand that the 13/14 GT500 rotor was also 15" and would probably work, I bought one to test.

The 07-12 GT500 rotor will not work, as it is 14". That's too large a difference to try a caliper designed for a 15" rotor.

 

[v6tungsten]

So 2014 gt500 rotor and 2015 6 piston caper work with no shimming required

 

[2Fass240us]

So 2014 gt500 rotor and 2015 6 piston caper work with no shimming required

correct

 

[2013sTang]

Awesome write up

 

[DTL]

Has anybody actually run this setup on a car yet? (besides just determining that they fit) I'm concerned that the piston volume of the '15 caliper vs the previous 4-piston would seriously screw up the bias, especially with a master cylinder designed for the smaller 4-piston caliper. Has anyone calculated the volume difference between the two?

 

[2013sTang]

Has anybody actually run this setup on a car yet? (besides just determining that they fit) I'm concerned that the piston volume of the '15 caliper vs the previous 4-piston would seriously screw up the bias, especially with a master cylinder designed for the smaller 4-piston caliper. Has anyone calculated the volume difference between the two?

Very good question, also interested

 

[fast Ed]

FWIW, 2013-2014 GT-500 used the same master cylinder as other S197 cars those years.


cheers
Ed

 

[Sky Render]

So to get those 6-pots from the '550 to work, you need:

1. S550 6-piston Calipers
2. '13-14 GT500 front rotors
3. '13-14 GT500 dust shields (optional)

Anything else?

 

[2Fass240us]

So to get those 6-pots from the '550 to work, you need:

1. S550 6-piston Calipers
2. '13-14 GT500 front rotors
3. '13-14 GT500 dust shields (optional)

Anything else?

lines

 

[2Fass240us]

FWIW, 2013-2014 GT-500 used the same master cylinder as other S197 cars those years.

cheers
Ed

Ed: Are you able to confirm the bore diameter of 1.063"? I'm using it to calculate hydraulic force to compare caliper options.

It looks like the above linked BMC is only for 2012-2014 models, but the cylinder diameter is the same across S197 MYs.