New owner, identifying STI brakes
 

Hi everyone!

I've been a follower of the forum since 2015 and i've finally picked up first BRZ (ZC6) ten years later.. :lol:

I need some help in identifying the brake setup being used, according to the previous owner, he retrofitted the STI brembos from the Subaru impreza STI (GRB) aka hatchback. I understand the PCD for the STIs are usually 5 x 114.3

Front are 4-piston calipers while the rears are 2.

The front rotors used are dual PCD, but the rears are the 5x100 pattern.

I am looking into swapping the already worn pads and rotors to slotted dixcels and perhaps S-type pads - could anyone guide me on the correct part numbers to order? perhaps via RHDjapan etc. I've reached out to dixcel's support as well and I would like to know has anyone tried this setup before.

I also understand the need to consider the internal diameter of the rear rotor due the brake shoe sizing.

Front brakes:
[IMG]https://i.imgur.com/cKdc7Aa.jpeg[/IMG]
[IMG]https://i.imgur.com/yBCg9da.jpeg[/IMG]

The shim has since been flipped according to the direction of rotation:
[IMG]https://i.imgur.com/0R1hTmh.jpeg[/IMG]

Rear brakes:
[IMG]https://i.imgur.com/uoMXc7s.jpeg[/IMG]


Here's also a picture of my current setup, looking forward for more interactions!
[IMG]https://i.imgur.com/WBL5PLx.jpeg[/IMG]

> also, how cautious do i need to be when removing and reinstalling the calipers? I've heard horror stories of the aluminium threads stripping due to repeated heat cycles. :confused0068:

I unfortunately don't have a definite answer, but these cars did have the option to come with Brembos from the factory. Having owned both an STi and a BRZ with Brembos, I'll say that visually there is no noticable difference and pads are definitely interchangable.

I do know the piston sizes are slightly different in the front calipers, but I *think* the overall caliper size is the same.

I'd personally look up specs for OEM replacement parts for the STi Brembos and the BRZ performance pack Brembos and compare. I'd bet they are the same.

As for removing them... that can definitely be a thing. Unfortunately there isn't much to be done and there isn't really a good way to be "careful" about it. It's kinda a "it'll break or it won't, but you gotta try to remove it anyways" sort of situation.

I will say that removing the bolts with an impact gun seems superior to removing with hand tools. Hand tools are more likely to slowly stretch the bolt and snap it whereas the sudden hit from an impact gun gives a better chance for success.

If the bolt does break, it's pretty straightforward and simple to helicoil the brakes and get back in action. It's a bit scary to do (definitely don't want to tap it at an angle or something), but as a first-timer with minimal experience with such things I had no problem doing it well.

I've had two STi's and a BRZ with Brembos. All 3 cars needed at least one caliper helicoiled eventually.

I don't know the salient differences to be able to confirm the source of the brake system. You'll have to find some more info/your own research. Otherwise, the basic 4pot/2pot Brembo BBK caliper bodies (and compatible pads/rotors) are ubiquitous across many different Subaru cars (and other cars). Some defining differences include

• Original orientation of brake bleeders
• Brake piston diameters
• Any visible part numbers

-------------------

You don't swap wheel hubs/PCD for brake calipers. The rotors are probably all going to be 5x100 on the car.

• Easy way to confirm: what is the PCD for all 4 wheels?
  • Probably 5x100

-------------------

If it's a factory Brembo BBK from a WRX STi, then it's the same pad and rotor as almost every other Subaru that uses the Brembo 4pot/2pot calipers (including BRZ) plus cars from many other makes/models share the same caliper system (such as 4pot from Mitsubishi LanEvo and Cadillac ATS V).

• Make it easy for yourself and just look for BRZ Performance Package (factory Brembo BBK for BRZ) compatible pads and rotors; 326x20mm front, 316x20mm rear.
• It also shares parts with the Brembo GT 4pot/2pot kit direct from Brembo
  • You have to exercise a little caution for the 4pot fronts because the GT kit can accept a thicker pad and rotor
  • 2pot rears on the GT kit should be practically the same

I don't know that much about the drum brake issue, but if it's using a 5x100 rotor then it's probably not going to encounter it. Again, you can likely just buy rotors compatible with BRZ Performance Package (factory Brembo BBK for BRZ) and you don't have to think about much else.

I'd also add to that the most likely reason your current rotors are dual-drilled is so that they can fit both a BRZ with Performance Package Brembos and an STI with the same diameter stock rotors, not because it's some weird Frankenstein setup - don't let that throw you off. ;)

Thanks for this! looks like i have to standby a set of helicoils sigh... hahaha. What size do you normally prepare for this?

Thanks for your input as well! Oh yes its definite the PCD is 5x100 for the BRZ, just that the confusion comes about since the GRB, or rather, most STis were 5x114.3

Guess the only way is to remove the rotor to measure the inner hat diameter (or by measuring the external hat to see if its the 190mm or 170mm setup), and then maybe helicoil the calipers... :(

My DBA Discs for the front PP Brembo setup were dual drilled because iirc the dimensions are the same as the STi


This is the brembo part code
https://www.bremboparts.com/europe/e...isc/09-7812-11


Here's the DBA one
https://dba.com.au/product/front-str...or-dba654s-10/