Been obsessing about brakes as some of you can tell and this question is probably just splitting hairs but I'm going to ask anyway. I like to learn.

I see two prominent choices for caliper stud kits: Tarett & GiroDisc.

These would be used for either GiroDisc or AP Racing (350/350) rotor upgrades for a Porsche 991.2 Carrera S where the rears would be going up from 330 to 350mm rotors, thereby requiring spacers and either longer bolts or longer studs.

The Tarett Parts are:
Front: BCSK-85
Rear: BCSK-95 (10mm longer for 20mm larger diameter rotor)
- Rear Sleeves Required for Tarret Studs: GDASBCS-95



The GiroDiscs Parts are:
Front: BCS-05
Rear: BCS-03 (10mm longer for 20mm larger diameter rotor)



Two Questions:
1) Any thoughts or opinions on the quality or fitment for either of the two stud kit options? My guess is that's they're probably roughly the same. Just wasn't sure if there's one that seems to work better than the other.
2) I don't see any sleeves that are required for the REAR GiroDisc brand studs. They are required for the Tarett studs. Am I missing something or are the GiroDisc longer studs for the REARs already pre-designed for this application in mind?

Thanks in advance!

 

i have the Girodisc studs. High quality. Perfect fit
Girodisc does not require sleeves and is drilled for safety wire . I have a Base and added the bigger rotors

 

Safety wired with the Girodisc studs

 

I don't really have a horse in this race, but from what I can see there is unlikely to be any appreciable difference between the two post-installation. If the prices are about the same, I'd go with the girodisc stuff as it's a name I am directly and positively familiar with, and it also has fewer parts to accomplish the same goal.

 

I have used both. I prefer giro disc because they didn't require a double nut installation. Instead you use a socket (8mm?) on the head to torque.

 

I just bought studs and went Girodisc because of the much easier installation with the integral 8mm hex on the head. The girodisc kit comes with everything you need, thread locker, thread chasers, washers, etc. Install was a breeze. Shop around and you can get them for $270 (both axles) delivered.

 

I went with Girodisc version. 3 reasons: (1) It has a hex head, no need to use a 2 bolt method to install. (2) It has the taller shoulder in the rear to add the 7mm spacers in order to run 350mm Girodisc rear (OEM is 330mm), but for OEM no issues (3) Girodisc comes with a thread chaser. I used Tarett in the past, same quality in terms of material and machining.

Don't forget to get the Tarett brake line bracket studs regardless which option you go with. A bit dissapointed Tarett doesn't use a simple USPS small envelop to ship a small bag of studs. The charge $23 for a box of UPS shipment.

As for the rotors, I went with Girodisc. Giro is quieter and costs less. I had AP on my last car, even with street pads they're super noisy on the street. Performance difference is splitting hair. Never heard any complaints about Giro.

Zero, absolutely zero noise from the Giro slots. "J" hooks are noisy, even if you taper grind the pads.

 

I've used Tarrett before on my Cayman with stock brakes and they were excellent.
An absolute must for swapping out pads for track.

That said, if I was tracking my C2S, I would going with Giro with no need for sleeves.

Also, re; the brake line studs,(I forgot) & I just made my own out some SS all-thread I happened to have.

 

You can make the brake hardware studs by using local grade 8 hardware at the hardware store for sure.
I'm doing Spiegler lines to make the brake changes a little easier. All 6 lines. really not needed, but nice to have as our cars are aging and those rubber lines at a minimum might fail.

 

@Jnosol Thanks for your reply. I just have a couple of questions about your comments. You used 7mm spacers? I thought you needed 11mm spacers for the rears when going from 330 to 350mm rotors. There's a whole long thread about this so I'm curious as to how you used just a 7mm spacer.

Also... And I'm no expert here but I always thought that the noise from bakes was more a product of the pads and not the rotors. I'm curious what pads are you using? I've never heard that J hooks were noisier than straight slotted rotors.

 

Caliper studs, or brake line studs? Not really sure I have seen anyone do the main caliper stud from a HW store.

 

I voted Tarett because that’s what I have. But after reading about Girodisc version, I’d probably go that route instead if I had to do it again.

 

FWIW...
In my experience, I have run AP Racing calipers & J hooks on two different cars and didn't experience extra noise.
For pads I switched out Ferodo street & track compounds.
Others may have a different experience.

 

I used whichever it came with it, probably was 11mm. I used DS2500 pads, even chamfered the edges and you can still hear the "J" hooks at low speed. It was like a nail on chalkboard for me, and I can tolerate NVH very well. Hell, my first car was a Honda with B16 solid aluminum motor mounts and straight pipes so NVH doesn't bother me much.

If you're just looking for pure performance, hard to beat AP's. Their coating is always superior to Giro, better high temp handling. Hat doesn't turn colors. But it is 20% higher price, I don't think you're going to get 20% longer life than Giro.

If I get another BBK, it will be AP 9669/9449. I think Giro started to make rotors for AP kits now if the noise bothers me again.





I meant brake line studs. As for caliper studs, it wasn't worth the time for me to invest the time to make my own studs. They're just M12x1.5 12.9 grade (304 stainless steel), double sided studs. Not hard to find from online stores like McMaster or Accu Components. I've sourced my own hardware to replace SPL suspension hardware. They're just bolts, as long as it meets the specs. If anything, the non-stainless 12.9 carbon steel are way stronger than what Giro or Tarett supplied. =)

 

@F355bob I ended up going with the GIroDisc studs for the variety of reasons already mentioned in this thread. Just seems like the best thought out design. Curious about your safety wire. I noticed the small holes at the end of the studs. Is that what they are for? Do you recall what gauge wire you used? I'm almost wondering if a cotter pin might be a good option instead of a wire. Nicely done either way.


@Jnosol
I went ahead with the Tarett brake line bracket studs. I have a 991.2 C2S with the S brakes. Looking at the photos of your rear brakes, I'm guessing you have the same brakes as mine. My Tarett brake line bracket studs came with 8 studs. I felt there was only the need to use two of them. On on each of the front wheel carriers. There is only 1 bolt attaching the brake line bracket on each of the wheel carriers that needs to be removed in order to do a pad/rotor change. I didn't have to detach any brake line bracket on the rear wheels when changing out the brakes (rotors and pads). I'm wondering why they include so many studs. The instructions state that some models will not require use of all parts, but I can't even figure out where to use the remaining 6 studs. Wondering if it could be for a different 991 (such as turbo or GT models that might have bigger/better brakes. Did you uses any studs besides the one on each of the front wheels?

For everyone else, let me just say that the GiroDisc studs installed easily and I'm happy I went with them.