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Girodisc 2-piece floating rotors

I have some experience with Girodisc two piece rotors on another car, but not on the Boss.

I ordered a set of front and rear rotors a few years ago for my 2004 Mitsubishi Lancer Evolution 8 RS which came with a similar brake setup to the Boss. It was the first time I had ever bought two piece rotors and Martin at Girodisc was helpful and patient with my many and often stupid questions. I was impressed with the quality of their product and the improvement in performance they provided.

The reduction in unsprung weight was noticeable to me in almost every way: accelerating, steering feel and responsiveness, braking, etc. In addition to the rotors, I also upgraded the pads and fluid and added SS lines at the same time, so while the difference in braking to me was truly night and day, it is hard to say how much of the change was a result of the rotors. Furthermore, I sold that car about a year later and was only able to get in one more track day with it. Therefore, I can't really comment on durability or long term performance.

George
 
and on the track attack question: the rotors on the TA cars are an FRPP part (or so I was told by a tech at MMP and by Mark Wilson)...don't know who makes it for them, though.
 

PeteInCT

#LS-378 - So many Porsche's, so little time....
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Never used them but the rumor is they are top shelf. Some of my PCar buddies use them, one on a GT3RS....
 
Thanks for all the feedback guys. Looks like a good option after I burn through the spare set of front rings and rears sitting on the shelf. I may order these once I install those so I have backups.
 

PeteInCT

#LS-378 - So many Porsche's, so little time....
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cloud9 said:
Thanks for all the feedback guys. Looks like a good option after I burn through the spare set of front rings and rears sitting on the shelf. I may order these once I install those so I have backups.

Are they cryo treated ?
 
fuhrius said:
and on the track attack question: the rotors on the TA cars are an FRPP part (or so I was told by a tech at MMP and by Mark Wilson)...don't know who makes it for them, though.

The cars at the Boss Track Attack utilize the brakes off of the FR500S. (These are functionally the same as the ones from the FR500C, the difference is that Mulitmatic made the adaptors and used a different brake line, aka “Grand-Am Brakes”)

4-piston Brembo calipers and 355mm (14") 2 piece floating rotors

Kit includes:
Calipers
Brake Pads
Brake lines (4 piece kit)
Rotors
Mounting hardware
Requires 18" or larger wheels

Ford Part Number M-2300-J / Cost $2,800.00 - $3,000.00 depending on vendor.

The caliper looks similar to the stock one but it is different, you can utilize a true endurance brake pad (it's thicker).

Also instead of the pin which has to be knocked out with a nail punch the FR500S Caliper utilizes a quick release pin.

The FR500S brakes are also noisy because of the two piece rotors………..
 
I have a set at the shop awaiting install on my 2012 GT.
Fronts, rears, 'Magic' pads (low dust, low noise), stainless lines, and Tilton TSR-1 fluid.

Mainly did it for the weight reduction, but if you're going to 'upgrade', do it right. Talk with Martin and he'll give you a rundown on what makes their rotors stand apart from the rest.
 

ArizonaBOSS

Because racecar.
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Arizona, USA
cloud9 said:
Thanks for all the feedback guys. Looks like a good option after I burn through the spare set of front rings and rears sitting on the shelf. I may order these once I install those so I have backups.

Gary--can you shed some life on the ring replacement costs, if you are looking into this further? Thanks.
 
ArizonaGT said:
cloud9 said:
Thanks for all the feedback guys. Looks like a good option after I burn through the spare set of front rings and rears sitting on the shelf. I may order these once I install those so I have backups.

Gary--can you shed some life on the ring replacement costs, if you are looking into this further? Thanks.

I called today and replacment rings ae just under $300.00 each and they include replacment hardware.
 
Boss_302 said:
ArizonaGT said:
cloud9 said:
Thanks for all the feedback guys. Looks like a good option after I burn through the spare set of front rings and rears sitting on the shelf. I may order these once I install those so I have backups.

Gary--can you shed some life on the ring replacement costs, if you are looking into this further? Thanks.

I called today and replacment rings ae just under $300.00 each and they include replacment hardware.
Thanks Doug. That is in line with DBA and Coleman. I like the fact they have a 2 piece rear. I will see how long these non-cryo treated DBA rings last compared to all the previous ones I had cryo treated before making a judgement on that.
 
Girodisc is an excellent product offering very nice reduction in un-sprung weight. Very popular choice in the STi community. Extensive thread can be found at www.IWSTI.com
 

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