cholmes1
400lb Gorilla
First I need to thank Paul @PAEracing for all of his assistance in April 2020 in discussing Brembo brake options with me. Paul's knowledge and customer service are outstanding and I would highly recommend him and his team to anyone looking for honest advice. I had originally approached Paul about the XB105 system utilized in the 302S and current Grand-Am touring cars for my '13 302LS. Regrettably, my knowledge of these systems was (and remains) limited and I was unaware of the noise dedicated race calipers generate (no anti-rattle clips, floating rotors, etc). Since my car only sees the track for the occasional solo sprint events (~ 1 / year) and is 99% street/show the rattle would have driven me nuts. This upgrade is purely to push my car forward in terms of potential capability, which I will never approach
I was originally going to stay FRPP with the GT350 setup but having Paul explain the significant weight difference between OEM and Brembo GT-S/Race while also following Full Tilt Boogie's testing the GT350 rears on the S197 platform and finding out they were incompatible in all situations, the GT350 calipers were a non-starter. Following these exchanges with Paul, I decided to go with the Brembo GT-S M6 setup upfront. So now that I plan on using the Brembo GT-S M6 upfront the search begins to find a suitable match in the rear.
* This is where I may lose the interest of some TMO members *
Being this brake swap is far less for need and more for 'potential' and aesthetics I feel I am hitting a bit of a wall. In speaking with Filip at Cortex and others I am aware the rear brakes really do not require modification beyond the disc and the pad for success on the track. To support, he stated that in GT4 testing Cortex found that anything beyond a 328x28 system was overkill and just adding weight. Hence why they offer the Brembo XA3 calipers on a 313x25 rotor to pair with their floating axle. That said, the Brembo XA3 is similar to the XB105 in that it is a true race caliper and would not only have similar noise issues but would be far beyond my need and not aesthetically match the GT-S M6 caliper. While my planned system may not be OEM at any level, finding a rear Brembo caliper that can match the M6 should allow me to have the improved braking I am looking for while also having the appearance of a matched system like you would find in higher-end OEM setups.
In research, it appears the GT-S M4 caliper is the perfect mate and has a broad variety of rear brake system options. The challenge now becomes determining how such a system could be installed in the rear. With the '13 302 having a solid rear axle nearly all aftermarket options are not compatible. After FTB's GT350 testing, they recommended I reach out to Cortex to inquire about their floating axle as it allows for a larger variety of rear brake options to be applicable while also allowing camber to be applied. Another issue encountered is that because my car is primarily road driven and for car shows, few of the Brembo GT-S options allow for a parking brake. Fortunately, Wilwood appears to offer a standalone electric parking brake kit that can be mounted anywhere on the caliper.
My questions for the TMO family are...
1) Does anyone know if the M4 caliper with 345 - 380mm disc can mount to the Cortex floating axle in the S197? I am unable to find the depth of the rotor hat. I would assume yes if the XA3 can, but my knowledge is limited
2) Has anyone used the Wilwood electric brake kit? I did find one M4 option that does include a mechanical brake (from the 2020 Mustang GT) but I am not certain how easily or if it could be connected to the existing handbrake.
3) Given my limited knowledge, does it appear I am missing anything with this potential setup (F: M6 w Ferodo FM1000 pads on a TY3 disc - R: Cortex Floating Axle using the Brembo M4 w Ferodo FM1000 pads on a TY3 disc and Wilwood EPB or Brembo mechanical PB)
I look forward to learning more from the collective knowledge of our group
I was originally going to stay FRPP with the GT350 setup but having Paul explain the significant weight difference between OEM and Brembo GT-S/Race while also following Full Tilt Boogie's testing the GT350 rears on the S197 platform and finding out they were incompatible in all situations, the GT350 calipers were a non-starter. Following these exchanges with Paul, I decided to go with the Brembo GT-S M6 setup upfront. So now that I plan on using the Brembo GT-S M6 upfront the search begins to find a suitable match in the rear.
* This is where I may lose the interest of some TMO members *
Being this brake swap is far less for need and more for 'potential' and aesthetics I feel I am hitting a bit of a wall. In speaking with Filip at Cortex and others I am aware the rear brakes really do not require modification beyond the disc and the pad for success on the track. To support, he stated that in GT4 testing Cortex found that anything beyond a 328x28 system was overkill and just adding weight. Hence why they offer the Brembo XA3 calipers on a 313x25 rotor to pair with their floating axle. That said, the Brembo XA3 is similar to the XB105 in that it is a true race caliper and would not only have similar noise issues but would be far beyond my need and not aesthetically match the GT-S M6 caliper. While my planned system may not be OEM at any level, finding a rear Brembo caliper that can match the M6 should allow me to have the improved braking I am looking for while also having the appearance of a matched system like you would find in higher-end OEM setups.
In research, it appears the GT-S M4 caliper is the perfect mate and has a broad variety of rear brake system options. The challenge now becomes determining how such a system could be installed in the rear. With the '13 302 having a solid rear axle nearly all aftermarket options are not compatible. After FTB's GT350 testing, they recommended I reach out to Cortex to inquire about their floating axle as it allows for a larger variety of rear brake options to be applicable while also allowing camber to be applied. Another issue encountered is that because my car is primarily road driven and for car shows, few of the Brembo GT-S options allow for a parking brake. Fortunately, Wilwood appears to offer a standalone electric parking brake kit that can be mounted anywhere on the caliper.
My questions for the TMO family are...
1) Does anyone know if the M4 caliper with 345 - 380mm disc can mount to the Cortex floating axle in the S197? I am unable to find the depth of the rotor hat. I would assume yes if the XA3 can, but my knowledge is limited
2) Has anyone used the Wilwood electric brake kit? I did find one M4 option that does include a mechanical brake (from the 2020 Mustang GT) but I am not certain how easily or if it could be connected to the existing handbrake.
3) Given my limited knowledge, does it appear I am missing anything with this potential setup (F: M6 w Ferodo FM1000 pads on a TY3 disc - R: Cortex Floating Axle using the Brembo M4 w Ferodo FM1000 pads on a TY3 disc and Wilwood EPB or Brembo mechanical PB)
I look forward to learning more from the collective knowledge of our group
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