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2011 REAR BRAKE UPGRADE/REPLACEMENT

195
323
Exp. Type
HPDE
Exp. Level
3-5 Years
Wisconsin
Over the winter I want to swap out/upgrade my rear brakes. I have the GT500 conversion on my car however I might be 5 plus years old. I really dont know. Question is...

Should I stay with this set up and just buy new calipers or is there a better 2 pist upgrade kit to buy. Again I want to replace the calipers as well as the rotors and pads.

FYI I will also be doing to 6 pis Brembo upgrade from my 4pot this winter as well.

Thank you for all the help!

Andy

PXL_20220302_180340912.jpg
 

ArizonaBOSS

Because racecar.
Moderator
8,627
2,555
Arizona, USA
IMO there is not a lot of value to trying to do much differently in the rear. I would just look at the pads that are coming out of there and see if there is any radial taper wear indicating that the caliper bridge may be flexing, if so, replace the caliper(s). But factory replacements are relatively inexpensive so no big deal.
I use the factory calipers in the rear on my race car, FWIW.
 
195
323
Exp. Type
HPDE
Exp. Level
3-5 Years
Wisconsin
IMO there is not a lot of value to trying to do much differently in the rear. I would just look at the pads that are coming out of there and see if there is any radial taper wear indicating that the caliper bridge may be flexing, if so, replace the caliper(s). But factory replacements are relatively inexpensive so no big deal.
I use the factory calipers in the rear on my race car, FWIW.

Do I just buy 12-14 gt500 rear calipers then? Seems oddly hard to find on the good old web.
 
I bought the adapter so I can run a larger rear rotor, had frozen rotors set me up with pads and rotors to match the 6 pistons up front with this setup ( adapter on ebay ). I did just buy the temperature brake paint ( something like 7 colors ) so I can see what temps I run front\rear and adjust from there.
 
441
387
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
If you already have the 2013-2014 Shelby GT500 set up on the rear their isn't much left to do. If you need calipers rebuild the factory calipers or buy new ones from Ford. Rebuilds do not hold up to the heat of track use. I went through 2 sets of Napa Eclipse premium rebuilds on the rear in a month or two. The second set started leaking after one track weekend. I bought new OEM from the local ford dealer and they have been on the car for a year with no issues.
 
195
323
Exp. Type
HPDE
Exp. Level
3-5 Years
Wisconsin
If you already have the 2013-2014 Shelby GT500 set up on the rear their isn't much left to do. If you need calipers rebuild the factory calipers or buy new ones from Ford. Rebuilds do not hold up to the heat of track use. I went through 2 sets of Napa Eclipse premium rebuilds on the rear in a month or two. The second set started leaking after one track weekend. I bought new OEM from the local ford dealer and they have been on the car for a year with no issues.

Nice, any chance you can hunt a part number for me?
 
195
323
Exp. Type
HPDE
Exp. Level
3-5 Years
Wisconsin

TMSBOSS

Spending my pension on car parts and track fees.
6,869
4,133
Exp. Type
HPDE
Exp. Level
5-10 Years
Illinois
Yep. The upgrade is a different bracket between the axel and the caliper bracket and the larger rotor. You can simply change the axel to caliper bracket. You may have to relieve (Grind) a bit of metal away to clearange the caliper bracket. A small die grinder or grinding wheel should work. It's been a few years since I modified mine. The single piston caliper is all you need in the rear. As front braking increases, demand for rear braking does not increase.
 
195
323
Exp. Type
HPDE
Exp. Level
3-5 Years
Wisconsin
Yep. The upgrade is a different bracket between the axel and the caliper bracket and the larger rotor. You can simply change the axel to caliper bracket. You may have to relieve (Grind) a bit of metal away to clearange the caliper bracket. A small die grinder or grinding wheel should work. It's been a few years since I modified mine. The single piston caliper is all you need in the rear. As front braking increases, demand for rear braking does not increase.

Ok then when shopping for new rotors, do I buy 12-14 gt500 rotors then? I know you need to do that for the 6pis upgrade.
 
441
387
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
Ok then when shopping for new rotors, do I buy 12-14 gt500 rotors then? I know you need to do that for the 6pis upgrade.
I am confused. The thread is about rear brake upgrade and this post is referring to 6 piston upgrade which is front brake upgrade. Which are you doing?
 
441
387
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
Rear sorry. Wanted to know what rotors I need to buy once I get new calipers. The gt500 calipers.
If you are moving to the 13-14 GT500 set up with the 13.8" rotors using the stock calipers you need to order the late 13 or 14 shelby GT500 rotors. There was an in year change so there are two rotor sizes listed for 2013. I usually order for the 2014 to make sure I don't get the small ones.
 
Is there really any benefit (besides looks) to upgrading to a 13/14 GT500 rear rotor? Seems like I've read as much negative as positive experiences, especially when using the adapters.
 
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Is there really any benefit (besides looks) to upgrading to a 13/14 GT500 rear rotor? Seems like I've read as much negative as positive experiences, especially when using the adapters.
It reduces heat and helps preserve rear brakes and axle seals on track especially if you are running with stability control on. Like you I don't love the looks of the adaptors. They may be fine but I would take the time to remove the axles and install the proper Ford brackets, do the job right and do it once no second guessing.

Other than heat management I don't recall any significant change in braking performance either pro or con.

You can find cautionary posts about bigger rear brakes throwing the balance all out of whack but I never found that to be the case. Just choose pads wisely as always.
 

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