Stock rotor Vs Girodisc....


HOOKED ON GT

GT Owner
Oct 26, 2006
468
Orlando & Australia
Don't do many track days (1 a year) but notice the front discs have a few cracks from the vent holes. Not every hole but many and some about 5mm long.
They function perfect, no hazing and perfect finish...but not sure of the tolerances for driving hard in their future.

Looked at Ford Parts for replacements and their "out of stock" and run $500 per disc and going to Gyrodisc is about the same price... hmm

Stu A
 

fjpikul

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Jan 4, 2006
11,475
Belleville, IL
There are some threads about this here. SpecRacer and Rocketman will be the most help here.
 

Specracer

GT Owner
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Nov 28, 2005
7,081
MA
I put Girodiscs on the front for this reason (at the time Girodisc suggested just doing the fronts). I also used Padgid yellow pads, which are a pad that can withstand demanding track use (I have 30 years of road racing experience). However no one, that I know of, has ever had an OEM brake rotor failure, and I also remember members of the design team saying they never had brake issues either (with the exception of the yellow car on the "stick" at Wixom, but that was an early ABS issue, if I recall)
 

69b302

GT Owner
Mark II Lifetime
Mar 13, 2021
97
Upstate NY
Drilled rotors generally do crack, if you drive them hard. Slotted rotors are better IMO for track duty. A two piece rotor will save a little rotating mass, which in competition can be an edge. Below is a general document(Originally Porsche data I think) on assessing rotor cracks.
0B90B64D-8157-4DD2-B84E-10A96008D07C.jpeg
 
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HOOKED ON GT

GT Owner
Oct 26, 2006
468
Orlando & Australia
Thank all of you for your gained experience on the middle pedal.....and getting that experience in the GT to the keyboard is invaluable.

I spoke to Scott this afternoon anddecided to do the Giro change out.

Might not (but fingers are crossed anyways) get them in time for Sebring next Friday

I also have the Pagid yellows for street use, but when hot ......amazing bite with feel.

Thanks Stuart A
 
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2112

Blue/white 06'
Mark II Lifetime
Why not use the Girodisc on all 4 corners?
 

Specracer

GT Owner
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Why not use the Girodisc on all 4 corners?
No reason other than budget. When I made the change, I spoke to Girodisc (this was before Scotts involvement), they suggested only the fronts. This surprised me, but their take, was obviously, the rears have less braking load, and heat, and OEM are fine. I would anticipate, their stance is different today. I doubt our "old" GT will see any more track time, so the way it is, will be just fine for the long haul.
 
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HOOKED ON GT

GT Owner
Oct 26, 2006
468
Orlando & Australia
Funny... my rears are in perfect shape, no cracks...but the callipers have changed colour to a green/gold hue after 1 track day.
The fronts colour looks factory even with the slight cracks appearing.

I do have a home made front ducting set up I add when heading to the track that might have helped?

With the help of a friend he's working on a 3D printed set up for rear brake cooling, but many more hurdles to jump yet on seeing if its got potential.

Im going to add some temp stickers to the calipers to see how they diff front/rear for next weeks run.... especially if I have to stay stock for one more track day....apples v apples

Ive ordered all 4 corners with the Girodisc set up, didn't want a weird non matching look.

Stuart A
 
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Specracer

GT Owner
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Nov 28, 2005
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My calipers are no longer silver, they are gold from the heat.

20200615_102353.jpg
 
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HOOKED ON GT

GT Owner
Oct 26, 2006
468
Orlando & Australia
I see nothing but a happy driver thats gone to level "GOLD MEMBER"
Did you go gold with stock rotors first?

Are your fronts gold?
 
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2112

Blue/white 06'
Mark II Lifetime
I am amazed how perfectly uniform that gold turned out.

I think it looks great.
 

MTV8

GT Owner
Mark II Lifetime
Jul 24, 2010
1,017
Houston Texas
Girodisc rotors should be superior to the stock parts in every way. They also face the correct direction on both sides of the car unlike the stock rotors.
 
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HOOKED ON GT

GT Owner
Oct 26, 2006
468
Orlando & Australia
Im intrigued in the science that's going on that can change grey to gold with heat.
I need Neil Degrasse Tysons number....
 

PeteK

GT Owner
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Apr 18, 2014
2,267
Kalama, Free part of WA State
I’ll take an educated scientific wild ass guess (SWAG): the original paint on the calipers was silver with a clear coat. As the calipers got hot, the clear coat got cooked and became yellow, thus making the silver color appear gold.
 
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HOOKED ON GT

GT Owner
Oct 26, 2006
468
Orlando & Australia
Just need to find a non clear coated caliper and set oven to 400+ deg and see if your SWAG is on the money
 
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HOOKED ON GT

GT Owner
Oct 26, 2006
468
Orlando & Australia
Ready 2 go......
Sorry ready to stop.

Scott was great to chat to and let me pic his brain. Plus he got the hustle on the discs so I had them in time.
Unfortunately too many GT's are just street driving/parked and the Girodiscs going out the door is far and few between nowdays ...

Stu A
IMG_4237.jpeg
 

2112

Blue/white 06'
Mark II Lifetime
Did you do the rears too?
 

HOOKED ON GT

GT Owner
Oct 26, 2006
468
Orlando & Australia
Nup....maybe oneday
 

fjpikul

GT Owner
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Le Mans 2010 Supporter
Jan 4, 2006
11,475
Belleville, IL
Is that a LCD thermometer on the caliper?
 

GT@50

GT Owner
Mark II Lifetime
Dec 14, 2019
852
Issaquah
Is that a LCD thermometer on the caliper?
Looks like heat tape. Looking forward to seeing temps and finding out when they turn gold.