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What’s needed to swap Shelby GT350R rear Brembos onto a PP S550?

Grintch

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Did some more searching online and found the install docs for the Ford Performance M-2300-Y GT350R front and rear brake kit.

I’m not seeing any mention of having to upgrade or replace the Master Cylinder in this document if putting this kit on anything other than a GT350R.... I also don’t see any mention of brake bias concerns.

?

Anyone have any ideas as to if brake bias would be an issue or if the MC is a concern on a GT or EB PP if upgrading to the GT350R kit?
Are you doing the full kit or just changing the rear? Changing the rear only will throw off the ballance. Especially if starting with a standard GT or EB PP (without the 15" front Brembos). Doing the GT350R brakes both front and rear should be OK as they are designed to work together.

Remember you will likely need new wheels to clear the larger brakes. In my book, not worth it for a street car or a HPDE car. Maybe worth it for a race car where every tenth counts, IF the class rules allow it.
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EVL-S550

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I looked into this because it annoys me the rears don't match. Wouldn't have been hard for Ford to have just done a 4 piston rear Brembo on the PP cars but then again, that would be one less thing to set apart the Shelby. You'll need the new parking brake assembly, knuckles from the GT350, plus the calipers and rotors, not to mention a new set of wheels as the rear PP wheels offset won't clear the calipers. By the time you add all the parts up a la carte, you're better off getting the whole GT350 brake upgrade kit from Ford Performance, especially since it comes with beefier GT350 halfshafts.
 

BmacIL

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I looked into this because it annoys me the rears don't match. Wouldn't have been hard for Ford to have just done a 4 piston rear Brembo on the PP cars but then again, that would be one less thing to set apart the Shelby. You'll need the new parking brake assembly, knuckles from the GT350, plus the calipers and rotors, not to mention a new set of wheels as the rear PP wheels offset won't clear the calipers. By the time you add all the parts up a la carte, you're better off getting the whole GT350 brake upgrade kit from Ford Performance, especially since it comes with beefier GT350 halfshafts.
And that's all a literal waste of money unless you're an expert driver on a road course. The GT PP brakes are excellent.
 

EVL-S550

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And that's all a literal waste of money unless you're an expert driver on a road course. The GT PP brakes are excellent.
Completely agree. New rotors + pads all around if tracking a PP car is better $ spent.
 

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Grintch

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No, it's the same on all S550's.
Not according to Vorshlag, who reported issues using the Ford Performance PP bake upgrade kit (without new master cylinders), and have thier own package that includes a new (PP?) master cylinder.
 

Grintch

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No, it's the same on all S550's.
Not according to Vorshlag, who reported issues using the Ford Performance PP bake upgrade kit (without new master cylinders), and have thier own package that includes a new (PP?) master cylinder.
 

EVL-S550

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Not according to Vorshlag, who reported issues using the Ford Performance PP bake upgrade kit (without new master cylinders), and have thier own package that includes a new (PP?) master cylinder.
Different brake booster is all I understood was different.
 

BmacIL

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Different brake booster is all I understood was different.
No, the master cylinder is definitely different, as is the booster. The MC has a larger bore. Vorshlag's issues were mainly because of too aggressive of a rear pad and hulk smashing the pedal. The hydraulic ratio difference between the 6 piston calipers and 4 pistons is less than 0.5% (I've done the math with the actual measured piston areas). The GT350 shares the same master cylinder as the base GT, and has FAR more rear bias, hydraulically.
 

Stage_3

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So,.........I'm a bit confused here and really would like to know.

For the rear GT350 Brembo big brake kit upgrade on a 2019 Mustang GT, why are the new halfshafts and the new rear spindles necessary? The fronts seem pretty cut and dry, but why the new halfshafts and newspindles for the rear upgrade?
 

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BmacIL

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So,.........I'm a bit confused here and really would like to know.

For the rear GT350 Brembo big brake kit upgrade on a 2019 Mustang GT, why are the new halfshafts and the new rear spindles necessary? The fronts seem pretty cut and dry, but why the new halfshafts and newspindles for the rear upgrade?
The caliper won't mount up to the stock rear spindle. Half shafts should be plug and play though, as GT350 ones fit the GT.
 

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The caliper won't mount up to the stock rear spindle. Half shafts should be plug and play though, as GT350 ones fit the GT.
Okay, that makes sense about the caliper. The half shafts, I'm all set with as I already have upgraded half shafts.
So this kit unfortunately is a no go for me. Too bad.

Thanks for your reply.
 

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I have upgraded my 2018 PP1 with 2 piece front rotors and better pads but the rear is still the SINGLE piston.... I use the car mainly for track days and have worn the rear pads out in less than 3000 miles. Below is a link from Wilwood on their 4 piston rear conversion kit for the PP1, Has anyone tried this conversion, it looks like it would be a great upgrade and will not brake the bank. I am thinking of doing this over the winter

https://www.wilwood.com/BrakeKits/BrakeKitsProdRear?itemno=140-13888
 

XCRN

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For the rear, I think it is possible to use the stock spindle. Looking at the components, the Ebrake mechinism is just some plate that sandwitches between the spindle and wheel bearing. I have not compared the 2 bare spindles side by side, but dimensionally they look similar. The E-brake plate is why the same wheel taken from the lower Mustangs will stick 1/4” further out when put on a GT350.
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Norm Peterson

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Didn't see this until today, following a link from some other thread.
I have upgraded my 2018 PP1 with 2 piece front rotors and better pads but the rear is still the SINGLE piston.... I use the car mainly for track days and have worn the rear pads out in less than 3000 miles.
Sounds more to me that your car's AdvanceTrac and/or traction control have been working overtime. If that's not the case - which would require running with them shut off - then the last thing you need would be to shift the brake balance more rearward.


Norm
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