dlefty

For the GTR and GTR PRO cars that have done the conversion from the factory carbon ceramic brake rotors over to the GiroDisc steel rotor conversion and been doing track days……

1)would you do the GiroDisc’s again, or are you more so-so on them than happy?

2)what brake pad options were you able to track down and experience?

3)Since the 402mm front GiroDisc rotor requires a different brake pad with an annulus (pad swept area) of 66mm or less, did you find this satisfactory to your track day experiences?

Any additional feedback?

canucklehead

Yes.
I switched to the Girodiscs. Love them. Wish I did it sooner before I wore out the CC rotors.
I think there are 2 options for pads direct from GD. I suppose with a little research there are probably other options.
I am happy with what GD offers as it does everything I ask of the brakes and so far I do not see any compromises other than perhaps heat soak.
Proper bedding is important. Risk of glazing the pads is pretty easy if you go full send right away.

I am faster since the switch, mostly due to improved skills and familiarity with the car now.
So the GDs are not holding me back.
After the initial purchase of rings, hats and pads; replacement rings are only about 1k per pair fronts and .85k pair rears vs about $4200 per disc for CCs.
I am getting about 12 track days out of a GD disc. 6 days out of a set of pads.
hen I switched the rotors out, they were almost a mil below min thickness. So maybe 2 more track days I could have pushed them. Call it 14 total.
The CC rotors I think I got maybe 24 track days out of them.

dlefty

Great feedback, thanks.
I am happy to hear the rotor feedback, as I simply refuse to use up the carbon ceramics on track!

I have been super disappointed in the lack of pad offerings but going to continue to look, good to hear the “house brand” GiroDisc pads are holding up for your use…..may get those ordered

user33

IIRC, your CC rotor-wear was not determined using a Carboteq analysis tool. If that's the case, I'd seriously question whether or not they're actually worn. I wrote a white paper describing why the WIS-specified measurement technique (using the wear-indicator spots) is essentially useless. IMO, the "weigh the rotors" technique is also likely to be extremely error-prone.

As we've previously discussed, I'm tracking mine with a Carboteq tool and they don't seem to be wearing very quickly ... though it's still a crap shoot as there's no published data on wear patterns so I can't be sure the "wear numbers" will decline linearly. Unlike what I've seen posted, I also find that the Carboteq tool produces different readings with the rims on the car versus off the car. I take the readings with the tool in about the same rotational place, each time, but also suspect that it may be different, again, if the rotor was off the car.

Anecdotal posted "data"/comments suggest that CC rotors may be able to withstand 40-50 track days. If that's true, then they would not be appreciably more expensive -- and would be much less labor intensive -- than iron rotors. I'm hoping that's true. $;-))

If you're ever in the Vancouver area, bring your rotors and I'd be happy to get some readings on them. If the tool wasn't so bloody expensive (>$9K CAD), I'd just send you the tool.

dlefty

GiroDisc rotor pad users, assuming everyone is using the GP30 front pad, but any experience between the GP20 rear pad and the newer GP25 rear pad? Curious as to the differences when in track.

amgeethx

Definitely go with the GP25 rear pads. The brake bias of this car is heavily forward and benefits from more aggressive rear pads to help even out braking duties. I am currently running Pagid RSL29 in the front and GP25 in the rear. The GP25's supposedly have about 15% higher coefficient of friction than the RSL29s according to Girodisc. The car is still very stable under braking and I had no problems with over rotation during trail braking.