I'm trying to answer that question.
For now, I'm holding off on the rear calipers/rotors as the IRS uses a different caliper design compared to that of the solid axle. Up front, things look quite a bit more promising. I'm going to compare the '15 GT350 setup to that of the '07-'12 GT500 Brembo rotor/caliper arrangement because it is far more popular than the '14-'15 GT500 brakes. That is not to say that you couldn't swap the latest Brembo/SHW hardware on the most recent GT500 as once you strip off the caliper and rotor you are left with pretty much the same spindle as used throughout S197 production.
So I started by taking a few key measurements off of a S197 wheel hub and sketched a model that would allow for fitment verification between the hub and each rotor. It isn't a complete model as it doesn't have to be - yet, anyway.
I have some NIB '07-'12 Brembo GT500 rotors in storage that I pulled out to dimension. They measured 13.9" in diameter, 1.259" thick, and have a hub register diameter of 2.797" (the hole in the rotor that mates with the stub portion of the hub). I mated the rotor/hub in Solidworks for a baseline. I didn't sketch the vanes as they aren't needed.
I then mated a sketch I did of the GT350 rotor to the S197 hub. I didn't sketch the vanes on the ring or the surface extrude cuts on the hat but the sketch has the proper base dimensions needed for this comparison. Note, the GT350 hubs use a 14mm wheel stud whereas the S197 hub uses a smaller, 1/2" x 20 stud. Same bolt circle between the S197 and the S550, just a minor difference in stud diameter. The SHW hub register matches the diameter on the Brembo rotor (thanks Ford!) and the hat thickness is the same between rotors as well (.315"). Looks good so far...
The GT350 rotor hat has 15 radial mounted pins that slip into the outer ring, allowing it to expand/contract as necessary. I sketched them as a simple straight pin but in reality they are shaped like a "T" (the length and diameter I used are correct). Note that they are offset in the friction ring as opposed to being located in the center. Anyway, by making the GT350 rotor transparent, you can see that it clears the fillets/chamfers where it mates with the hub.
I then slipped a purple-ish/transparent GT500 Brembo rotor into place so that you could visualize the difference in fitment between the two. The GT350 rotor is a monster in comparison to the earlier rotor.
You can see that Ford moved the rotor inwards, which would make sense as a larger diameter rotor teamed with the equally massive six piston Brembo caliper, need to leave room for wheel clearance. How do the rotor face locations compare when using an S197 hub? The outer rotor face moves in .31" on the GT350 SHW.
The inner rotor face moves in by .45" (that's almost 1/2" for the Common Core generation).
That inner dimension means that the rotor face is now even closer the the steering arm on the spindle as well as the outer tie rod end. I need to verify the clearances there as things were already in fairly close proximity. If the rotor makes it past that potential hurdle the next one becomes how to attach the new GT350 radial mount caliper since the S197 spindle to caliper bolts are perpendicular to the rotor instead of parallel on the GT350's knuckle/caliper arrangement. That can be remedied with a bracket/studs, much like Brembo already uses (as does Stoptech, etc) on typical big brake kits. Here's a sketch of a Wilwood bracket that attaches to an S197 spindle to allow a radial mount caliper.
I'm unsure as to caliper clearance as I don't have any data on the six piston beauty from Brembo but I'm working on it. If it gets a pass that would mean a simple bolt-on up front. Bias may not be optimized depending on your current rears but that could be attended to easily enough. I'm waiting on Ford Parts to release some GT350 hardware for verification so it may be a bit before I can do an actual mockup. Could be a nice mod using factory Ford hardware.
For now, I'm holding off on the rear calipers/rotors as the IRS uses a different caliper design compared to that of the solid axle. Up front, things look quite a bit more promising. I'm going to compare the '15 GT350 setup to that of the '07-'12 GT500 Brembo rotor/caliper arrangement because it is far more popular than the '14-'15 GT500 brakes. That is not to say that you couldn't swap the latest Brembo/SHW hardware on the most recent GT500 as once you strip off the caliper and rotor you are left with pretty much the same spindle as used throughout S197 production.
So I started by taking a few key measurements off of a S197 wheel hub and sketched a model that would allow for fitment verification between the hub and each rotor. It isn't a complete model as it doesn't have to be - yet, anyway.
I have some NIB '07-'12 Brembo GT500 rotors in storage that I pulled out to dimension. They measured 13.9" in diameter, 1.259" thick, and have a hub register diameter of 2.797" (the hole in the rotor that mates with the stub portion of the hub). I mated the rotor/hub in Solidworks for a baseline. I didn't sketch the vanes as they aren't needed.
I then mated a sketch I did of the GT350 rotor to the S197 hub. I didn't sketch the vanes on the ring or the surface extrude cuts on the hat but the sketch has the proper base dimensions needed for this comparison. Note, the GT350 hubs use a 14mm wheel stud whereas the S197 hub uses a smaller, 1/2" x 20 stud. Same bolt circle between the S197 and the S550, just a minor difference in stud diameter. The SHW hub register matches the diameter on the Brembo rotor (thanks Ford!) and the hat thickness is the same between rotors as well (.315"). Looks good so far...
The GT350 rotor hat has 15 radial mounted pins that slip into the outer ring, allowing it to expand/contract as necessary. I sketched them as a simple straight pin but in reality they are shaped like a "T" (the length and diameter I used are correct). Note that they are offset in the friction ring as opposed to being located in the center. Anyway, by making the GT350 rotor transparent, you can see that it clears the fillets/chamfers where it mates with the hub.
I then slipped a purple-ish/transparent GT500 Brembo rotor into place so that you could visualize the difference in fitment between the two. The GT350 rotor is a monster in comparison to the earlier rotor.
You can see that Ford moved the rotor inwards, which would make sense as a larger diameter rotor teamed with the equally massive six piston Brembo caliper, need to leave room for wheel clearance. How do the rotor face locations compare when using an S197 hub? The outer rotor face moves in .31" on the GT350 SHW.
The inner rotor face moves in by .45" (that's almost 1/2" for the Common Core generation).
That inner dimension means that the rotor face is now even closer the the steering arm on the spindle as well as the outer tie rod end. I need to verify the clearances there as things were already in fairly close proximity. If the rotor makes it past that potential hurdle the next one becomes how to attach the new GT350 radial mount caliper since the S197 spindle to caliper bolts are perpendicular to the rotor instead of parallel on the GT350's knuckle/caliper arrangement. That can be remedied with a bracket/studs, much like Brembo already uses (as does Stoptech, etc) on typical big brake kits. Here's a sketch of a Wilwood bracket that attaches to an S197 spindle to allow a radial mount caliper.
I'm unsure as to caliper clearance as I don't have any data on the six piston beauty from Brembo but I'm working on it. If it gets a pass that would mean a simple bolt-on up front. Bias may not be optimized depending on your current rears but that could be attended to easily enough. I'm waiting on Ford Parts to release some GT350 hardware for verification so it may be a bit before I can do an actual mockup. Could be a nice mod using factory Ford hardware.