Copper Free 6th Gen Front Brake Conversion?

[alocker]

Has anyone performed a Copper Free front brake conversion on a 5th gen?
This is the BCD/J6H option that used the CT5-V Blackwing calipers and 398mm 2-piece steel rotors.

I want to install on my 2015 1LE since they have a factory 1LE badged caliper. The plan would be the following.

LF Caliper 86791548
RF Caliper 86791549

GM GENUINE 85137534 Rotors-Appear to be the same for left and right.

ZL1-CTS-V rotor hats to install into above rotors.

2015 ZL1 Brake Hoses
Hardware Kit
Pads TBD

Will it work?

This is a street application and just doing it for fun.

[CamaroCracka]

Copper free only refers to pads, but that setup sounds like the Gen6 ZLE brakes. The offset on the hat is incorrect (off by 10mm) on the Gen6 so you need Z28 iron conversion rotors from GiroDisc.

You can make it work with Z28 or ZR1 hats, but good luck finding those. The ZR1 hats were made for 12mm studs so you have to drill them.

Honestly, if you are not tracking it, you don't need that much brake, but they do surprise anyone who notices them.

[alocker]

Originally Posted by CamaroCracka

Copper free only refers to pads, but that setup sounds like the Gen6 ZLE brakes. The offset on the hat is incorrect (off by 10mm) on the Gen6 so you need Z28 iron conversion rotors from GiroDisc.

You can make it work with Z28 or ZR1 hats, but good luck finding those. The ZR1 hats were made for 12mm studs so you have to drill them.

Honestly, if you are not tracking it, you don't need that much brake, but they do surprise anyone who notices them.

Hey Cracka, I appreciate the help. The 6th gen copper free brakes specifically the J6H was a $500 option required for California V8 cars or anyone that wanted to pay the extra in other states. Due to the reduction in performance of the pad compound, the rotors and calipers are larger. Larger than the Z28 and ZLE standard package. They measure 398mm or 15.67".

I guess my real question is, do all the Brembo hats have the same rotor ring bolt pattern. I understand the difference between the models, I just need to find out of the 398mm rings will bolt to a zl1 hat.

[CamaroCracka]

Sorry, the Gen5 ZL1 hat has a larger bolt pattern than either the Gen6 ZLE or the Gen5 Z28. It is what allows for the wider pad that gets closer to the hub and gives it so much swept area. I have never seen the copper free rotors and calipers, but the Gen6 rotors are 390mm. It would not make sense to increase the size of the rotor to improve braking but give up the added swept area the smaller hat provides.

In my experimentation I found three things changed with the Brembo hats I got a hold of. 1. The bolt pattern/hat diameter got smaller with the bigger brakes. 2. The offset changed depending on what car the hat came off of and 3. The hole size for the wheel studs changed depending on whether the car had 12mm or 14mm studs.

It's odd that the copper free and the ZLE brakes have the same J6H RPO code.

I'm thinking GiroDisc does not have a 398mm rotor for a Gen5 given the Z28 had the largest brakes at 390mm. The GiroDisc hats only work with GiroDisc rotors.

For pads, you would have to use replacements for the copper free package which could be hard to find unless you go with a performance pad from any of the mfgs like Hawk, Baer, etc.

FYI, 18" wheels barely clear the 390mm setup, so I'm thinking 19s would be a minimum.

KNS has the bolt kits should you find an appropriate rotor hat combination.

[alocker]

Ok, this further clarifies. I know this is a futile project because of how the car gets used but then again, it's ridiculous that I own it in the first place.

See the attached for the rotor specs. Maybe both RPO codes combined get you the larger rotors. Either way, I was thinking KNS would be a good resource when they open back up.