Rear disc brake kit 11" NEW DESIGN

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Esteban
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Re: Rear disc brake kit 11" NEW DESIGN

Post by Esteban » Fri Feb 24, 2017 6:55 pm

The adapters are pretty stout. They are not gonna twist. The bolts will be weak point if any but Tim provides 10.9 in his kit. I haven't driven on them much other than the 15 min drive home but i like them better than the Scorpio's and these arent even broken in yet. Firmer pedal, nice bite, lighter, and more pad choices. Tim really did his homework on this one!

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Re: Rear disc brake kit 11" NEW DESIGN

Post by timxr8 » Sun Feb 26, 2017 6:43 am

John Brennan wrote:Question:
It seems to me that a lot more stiffness and strength could be realized by extending the bracket sides down to include the lower bolts on the hub.
I was originally looking at this from that exact standpoint. What made me change my mind was Ford's own Motorsport prepped Sierras. They used adapters similar to mine with their 4 piston, hydraulic handbrake rear brakes. Although, made out of Aluminum which is stiffer (stiffie, depending how you much you like looking at them). My original design used a 3/8" thick bracket, but the 5/16" centered the rotor in the bracket. The strength of the bracket is still adequate and stiffness is still more than sufficient. I would actually argue that the extended ear does very little, if nothing, for strength and rigidity since the lower mounts give no added width to the bracket.
John Brennan wrote:Since the bracket is Mike's adapters for the T-Bird rears go full circle here, and most Scorpio rear adapters go down at least on one side. Anyone else think this would be a good measure against flex?
I think this is a terrific and well-researched solution, but this is the only thing I wonder about.
DG did the T-Bird's originally. Since the offset required the bracket to be placed behind the bearing carrier, there was a necessity to make it as a spacer to maintain wheel geometry. There's only been 1 Scorpio brake adapter design. All others were simply a direct copy. Both had been made out of 1/4" steel, which is far more flimsy. (MC2's Focus SVT brackets are an exception, which used a 5/16" thick bracket and a 1/4" stepdown at the caliper mount). The extra 1/16" makes a very big difference in strength. Mine are 25% thicker.

Also, as a comparison, the PBR setup uses 1/4" thick brackets in a position that sees roughly 2-3 times the amount of force (overall braking action, not individual component force). Granted, the moment is smaller on the PBR, but not that much smaller. Moment on the rear mounts at the upper bearing bolts is ~115mm, while for the PBR at the brake mount is ~70mm. That gives the rear brakes about a 65% increase in moment at the mount compared to the front. That is about the most of what can be expected for bias at maximum braking. The amount of offset in both cases is minimal, so there is not a lot of twisting forces applied to warp the brackets. Also, again, mine are 25% thicker.

I've looked at similar kits and their designs. Maximum Motorsport has an almost exact same kit for the Focus rear. It does bolt behind the rear spindle, but using a much smaller bolt circle compared to the XR. Theirs requires about a 3/4" set of spacers to move the caliper out on the rotor. They utilize 1/4" 1018 steel and have seen minimal flex on their 400hp roadrace Focus. I spoke with them regarding this extensively since the car weight and brake system sizing are nearly identical to the XR. They even cut little windows in theirs to reduce weight.
Tim Spencer
1988 XR4Ti Duratec project car
2011 Taurus SHO daily driver...not stock.

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Re: Rear disc brake kit 11" NEW DESIGN

Post by John Brennan » Sun Feb 26, 2017 12:52 pm

Thank you.
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Re: Rear disc brake kit 11" NEW DESIGN

Post by XR4ti614 » Sun Mar 12, 2017 2:25 pm

Doing my research on the parts list for this kit and would love to hear everyone's specifics of sourcing rotors, calipers, and pads.

How I understand the basics for this kit;

1. 2002-2004 Focus SVT rear rotor
2. 2012+ Focus (trim level?) rear calipers
3. 2012+ Focus ?? pads
4. Braided steel brake line from Merkur Depot.

Thanks!

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Re: Rear disc brake kit 11" NEW DESIGN

Post by Esteban » Mon Mar 13, 2017 2:26 am

I got my rotors from Rockauto, pads from Amazon, calipers and brackets from where you can find a good pair cheap. I believe the Focus from 12-16 have the same rear calipers regardless of trim. Braided lines, can get them from Merkur Depot but request them at least 2" longer than normal to help clear springs while routing.

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Re: Rear disc brake kit 11" NEW DESIGN

Post by merkurdriver » Mon Mar 13, 2017 10:54 am

Esteban wrote: Braided lines, can get them from Merkur Depot but request them at least 2" longer than normal to help clear springs while routing.
We don't make the lines, they are made for our Scorpio / Cosworth rear disc brake kit - supplied in a specific length. I was under the impression that people were using our lines with Tim's kit as well "as - is".

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Re: Rear disc brake kit 11" NEW DESIGN

Post by Spaldino » Mon Mar 13, 2017 12:57 pm

Esteban wrote:I got my rotors from Rockauto, pads from Amazon, calipers and brackets from where you can find a good pair cheap. I believe the Focus from 12-16 have the same rear calipers regardless of trim. Braided lines, can get them from Merkur Depot but request them at least 2" longer than normal to help clear springs while routing.
Which rotors and calipers did you go with? I was looking at rockauto last night and pricing out my options. Rotors don't look like it'd be an issue as they are pretty inexpensive comparatively. the issue i had was with the calipers.... wasn't sure which to get. I want to hit up a Ford dealer for them but i'm sure they would bend me over hardcore there.

I'd still have to paint the calipers as they all seem to be bare metal no matter where I look. I suck at painting.
88 Mono-white XR: Side exhaust, Walbro, MC2 Front Adjustable Coilovers, Rear Bilsteins, Full Poly bushings, MC2 Diff Mount, Rapido intercooler, Some sort of mild cam(?), Rear Disc conversion, 225s on 17x8 wheels.

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Re: Rear disc brake kit 11" NEW DESIGN

Post by XR4ti614 » Mon Mar 13, 2017 2:21 pm

Regarding the brake lines;
timxr8 wrote:
Hose length I would recommend is 24" for clearance around the spring. Mike's (Merkur Depot) will work, but ensure it remains clear of the spring so it doesn't get caught between a couple coils. AFCO makes some really nice Kevlar ones, but you can get the Russell DOT ones too:
AFCO 6684053-24
Russell: 656062

On Jeff's we used a pair of the Russell DOT 15" with a 90 deg end. The trick is ensuring there is clearance from both the spring and from the spinning axle.

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Re: Rear disc brake kit 11" NEW DESIGN

Post by Esteban » Mon Mar 13, 2017 7:39 pm

I bought my calipers and brackets from Tim after he rebuilt them. You can grab any unloaded caliper you find at a good price as I believe they're all the same quality. What will get you is the core charge. The calipers and brackets are almost always bare. Painting is definitely an option but not necessary.

Rear rotors: I like Centric blanks. Works great in autox and cheap to replace. Get 12561074 as they already have the hub and outer e-coated for protection. Saves you from painting.

As for the brake lines, we tried reusing the SS lines from Mike but since the line now comes from the front of the caliper, it was too close to the spring coil for comfort. You can use similar SS lines that are just longer, but what I ended up doing was using a pre-made Russell brake line with an adapter on each end.

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Re: Rear disc brake kit 11" NEW DESIGN

Post by XR4ti614 » Mon Mar 13, 2017 8:21 pm

Thanks for sharing. Seeing pulled parts calipers for as low as 35 +shipping, but I may just go refurbished. Digging the Rayspestos EHT pads that Tim had on the mock up. $45 for 2 sets I think, at Rockauto.

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Re: Rear disc brake kit 11" NEW DESIGN

Post by cmouta » Fri Mar 17, 2017 12:56 pm

XR4ti614 wrote:Thanks for sharing. Seeing pulled parts calipers for as low as 35 +shipping, but I may just go refurbished. Digging the Rayspestos EHT pads that Tim had on the mock up. $45 for 2 sets I think, at Rockauto.
Don't forget, those pulled calipers probably don't come with the focus caliper brackets that you also need. I've been eyeing similarly priced units on ebay but when you have to buy the brackets separately and account for separate shipping, it feels like it makes more sense to buy the refurbed caliper+bracket sets on rockauto.
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Re: Rear disc brake kit 11" NEW DESIGN

Post by timxr8 » Fri Mar 24, 2017 4:27 pm

merkurdriver wrote:
Esteban wrote: Braided lines, can get them from Merkur Depot but request them at least 2" longer than normal to help clear springs while routing.
We don't make the lines, they are made for our Scorpio / Cosworth rear disc brake kit - supplied in a specific length. I was under the impression that people were using our lines with Tim's kit as well "as - is".
You can use them, they will barely clear the spring. I have not seen any dynamic testing. At full extension of the STA (furthest length of the hose) it will touch the spring, but does not seem to go between the coils. It was something I observed on Esteban's car when we installed the brakes. I suggested the 24" length to ensure that distance is increased.
cmouta wrote:Don't forget, those pulled calipers probably don't come with the focus caliper brackets that you also need. I've been eyeing similarly priced units on ebay but when you have to buy the brackets separately and account for separate shipping, it feels like it makes more sense to buy the refurbed caliper+bracket sets on rockauto.
Every time I have purchased calipers (3 times now) I have received the bracket and all. All sets were $70-80 a pair shipped. On a car that is less than 5 years old. I'm putting some pull-offs on my wife's 2010 focus.

Make sure they are for a focus, if they show the C-Max, make sure you ask. C-Max and Escape use a 280mm rotor, while the Focus uses a 271mm. The bracket will have either a "280" or a "271" cast into the top of it. Make sure you get the "271".
Tim Spencer
1988 XR4Ti Duratec project car
2011 Taurus SHO daily driver...not stock.

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Re: Rear disc brake kit 11" NEW DESIGN

Post by my8950 » Tue Apr 04, 2017 11:57 am

I had an idea that would probably help out a lot of people, and since I suck at trying to make sense of threads with parts scattered all over.
Could someone make a part list of what is required and make a sticky?
Even if you can go on Rockauto and put all the necessary crap in a cart and take a screen shot of it and sticky it.
That would push me in the direction of using this rear setup instead of just thinking about how to make a part list.

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Re: Rear disc brake kit 11" NEW DESIGN

Post by timxr8 » Wed Apr 05, 2017 4:12 pm

my8950 wrote:I had an idea that would probably help out a lot of people, and since I suck at trying to make sense of threads with parts scattered all over.
Could someone make a part list of what is required and make a sticky?
Even if you can go on Rockauto and put all the necessary crap in a cart and take a screen shot of it and sticky it.
That would push me in the direction of using this rear setup instead of just thinking about how to make a part list.
I left it up to people to figure out what they want based on guidance (Year and make of different parts). There is a wide range of how people assemble a brake kit. There are very cheap rotors (Pronto), and very expensive rotors (EBC). Used calipers, reman, or new. Hoses pretty much have to be custom, but even then, many options. So, to give a specific parts list might not be the best option for someone looking to customize their own. If it helps, here's an example:

Rotors (2002-2004 Focus SVT): CENTRIC 12561074
Calipers (2012+ Focus: all, incl ST): A1Cardone 19B6284B and 19B6285B
Hose Option 1: MerkurDepot
Hose Option 2: Adapters (2x packages for 4 total): Russell RUS-R41431 and Hoses (2x): Afco AFC-6684053-24

That should point you in the right direction. Let me know if you need anything else.
Tim Spencer
1988 XR4Ti Duratec project car
2011 Taurus SHO daily driver...not stock.

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Re: Rear disc brake kit 11" NEW DESIGN

Post by my8950 » Wed Apr 05, 2017 8:01 pm

timxr8 wrote:
my8950 wrote:I had an idea that would probably help out a lot of people, and since I suck at trying to make sense of threads with parts scattered all over.
Could someone make a part list of what is required and make a sticky?
Even if you can go on Rockauto and put all the necessary crap in a cart and take a screen shot of it and sticky it.
That would push me in the direction of using this rear setup instead of just thinking about how to make a part list.
I left it up to people to figure out what they want based on guidance (Year and make of different parts). There is a wide range of how people assemble a brake kit. There are very cheap rotors (Pronto), and very expensive rotors (EBC). Used calipers, reman, or new. Hoses pretty much have to be custom, but even then, many options. So, to give a specific parts list might not be the best option for someone looking to customize their own. If it helps, here's an example:

Rotors (2002-2004 Focus SVT): CENTRIC 12561074
Calipers (2012+ Focus: all, incl ST): A1Cardone 19B6284B and 19B6285B
Hose Option 1: MerkurDepot
Hose Option 2: Adapters (2x packages for 4 total): Russell RUS-R41431 and Hoses (2x): Afco AFC-6684053-24

That should point you in the right direction. Let me know if you need anything else.
This helps, at least helps me. Thank you for your time.

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