Anyone using Girodisc's rotors?

Discussion in 'GT350 and S550 Technical Forum' started by honeybadger, May 16, 2018.

  1. honeybadger

    honeybadger TMO Intermediate

    Messages:
    10
    Likes Received:
    4
    Joined:
    Jan 29, 2018
    Location:
    Seattle Area
    Hi all -

    Planning for some big trips to some very high speed tracks this summer and working through my list of consumables. I'm exploring brake options before I commit and am wondering if anyone has tried the Girodisc rotors for heavy track use? Wanted to see if anyone has some real feedback/data points to share?

    I'm currently testing out Raybestos ST43s on the OEM rotors. When I used G-Loc R16s last year, the OEM rotors last 15 track days before they were toast. But that was before R compound tires, which are looking like they might cut the life by 1/3rd or so.

    I have 8 track days scheduled within a 2ish week time period that will be hell on the brakes and am looking for something maybe more durable. Thoughts? Anyone have real feedback?
     
  2. ArizonaBOSS

    ArizonaBOSS Because racecar. Moderator

    Messages:
    7,598
    Likes Received:
    986
    Joined:
    Dec 6, 2010
    Location:
    Arizona, USA
    My CorteX cambered rear axle comes with GiroDisc rotors and they seem to be quite stout.
     
    honeybadger likes this.
  3. captdistraction

    captdistraction Not necessarily the Stig

    Messages:
    1,203
    Likes Received:
    510
    Joined:
    May 16, 2012
    Location:
    Phoenix, Az
    I am running them and so far so good. They dropped 10lbs a side for me (380x32) but have enough mass to deal with the heat I generate under braking. Have 8 days on them so far and just starting to see slight heat fatigue cracking (I’d estimate about 1/3 life). Running R18 pads in w2w race use.
     
    honeybadger and ArizonaBOSS like this.
  4. VoodooBoss

    VoodooBoss Rick Moderator

    Messages:
    18,775
    Likes Received:
    1,451
    Joined:
    Nov 30, 2010
    Location:
    90 Miles East of Sonoma Raceway
    To me this is a cost factor question. You can buy 2-3 sets of rotors for one set of replacement rings. I’d wait to see if the GT500 has slotted rotors as rumored.
     
    RaiderJatt02 and ArizonaBOSS like this.
  5. barspen

    barspen TMO Intermediate

    Messages:
    98
    Likes Received:
    25
    Joined:
    Jul 30, 2016
    Location:
    Phoenix, AZ
    I'm planning on buying them soon, although I wont get them on the car until it starts to cool off in the desert southwest (Oct). Moving to G-Loc R12 on the fronts and plan to swap to GS1 between events.

    One reason I really like Girodisc verses others, they have spring clips on the hats that keep the noise level down for a floating rotor. Might not be an issue for a dedicated track cars, but on the street, sounds like 'full floating' can get annoying.
     
    honeybadger likes this.
  6. honeybadger

    honeybadger TMO Intermediate

    Messages:
    10
    Likes Received:
    4
    Joined:
    Jan 29, 2018
    Location:
    Seattle Area
    This is definitely an option I hadn't thought of. I thought I read rumors that the brakes were going to be bigger on the GT500 since it was using 20in wheels, so I didn't really think of it as an option. I was mostly exploring if Girodisc rotors would improve longevity and could handle abuse better enough to justify the cost.

    So far it seems most have assumed that they aren't worth the cost over OEM on the GT350 (probably rightfully so). Am hoping someone who is running them hard on track can provide some feedback to either direction.
     
  7. honeybadger

    honeybadger TMO Intermediate

    Messages:
    10
    Likes Received:
    4
    Joined:
    Jan 29, 2018
    Location:
    Seattle Area
    Good to know they're holding up well to your racing applications. I've heard good things - definitely tempted.
     
  8. Drlee50

    Drlee50 TMO Intermediate

    Messages:
    61
    Likes Received:
    11
    Joined:
    Sep 3, 2017
    Location:
    US
    10 or 15 track days on stock rotors is great ! Hard to beat that for the price. I get 1 weekend , maybe 2 on the boss 302. I run slicks and stock abs module tho. Hoping the 302r abs module helps. I run g-loc r18. I'm sure your larger pads and calipers help a bunch.

    Sent from my LG-H932 using Tapatalk
     
  9. VoodooBoss

    VoodooBoss Rick Moderator

    Messages:
    18,775
    Likes Received:
    1,451
    Joined:
    Nov 30, 2010
    Location:
    90 Miles East of Sonoma Raceway
    I’ve used Stoptech two piece before, which are very similar to the Girodisc, and I expect the Girodisc to last longer than stock GT350 rotors. I’m not sure the brakes are bigger on the 500.
     
    honeybadger and RES_22 like this.
  10. OPMustang Tim

    OPMustang Tim TMO Race

    Messages:
    239
    Likes Received:
    186
    Joined:
    Jul 9, 2016
    Location:
    Sunny Florida where it does not snow.
    A majority of our GT350 Customers have swapped to the Girodisc on the GT350. The cracking on the OEM ones is usually the main reason. The other reason is the holes will cause scalloping in the rotor when running an aggressive pad. Holes tend to act like a cheese grater on a pad. This causes odd wear patterns in the rotor and obviously shortens the life span of the pad. The one 'benefit' of the holes is once the rotor gets scalloped you now have more effective braking surface area due to the hills and valleys. The slotted Girodisc while still provided some pad aggression it is not nearly as pad agressive as the holes. There is some question as to the OEM rotor material at elevated temperatures (Slicks, COTA, R16-R18 pads) being capable of handling the conditions leading to accelerated wear but mostly We feel the 'marketing' holes are to blame. The Girodisc also does remove some weight (not a huge amount) despite the size of the ring but also provides a better air pumping action due in part to the ventilation vanes which manages heat more effectively.
     
    honeybadger likes this.
  11. honeybadger

    honeybadger TMO Intermediate

    Messages:
    10
    Likes Received:
    4
    Joined:
    Jan 29, 2018
    Location:
    Seattle Area
    Thanks for the insight, Tim! Any more specific insight on the longevity of Girodisc rotors compared to OEM?

    I'm actually moving to Texas and will be running COTA a couple of times a year. Also should mention that the road trip I am taking will include Road Atlanta, VIR, Road America, and Watkins Glen - the brakes will see some serious abuse. I would only expect 6-8 days out of the rotors (assuming no mistakes, bad wear, etc.) in those conditions.

    Unrelated - have you seen or heard of anyone adding proper brake duct cooling for the 350 yet?
     
    ArizonaBOSS likes this.
  12. VoodooBoss

    VoodooBoss Rick Moderator

    Messages:
    18,775
    Likes Received:
    1,451
    Joined:
    Nov 30, 2010
    Location:
    90 Miles East of Sonoma Raceway
    Drilled rotors suck. Why oh why do manufacturers continue to use them? Anyway the GT500 is supposed to have slotted rotors and will hopefully be able to replace the drilled rotors on the GT350.
     

Share This Page