[JJ91284]

I'm looking for a few specs on our Focus ST's. I'm hoping someone here know which would save me a trip from heading over to my autoparts store and ordering a set of calipers just for dimension sake.

Focus ST 2013+
Front Caliper Piston Dimensions 57mm OD and 51mm overall length
Rear Caliper Piston Dimensions 38mm OD and 50mm overall length
Front Caliper Bracket Bolt Size M14-2.0x35 hex flange
Rear Caliper Bracket Bolt Size M10-1.50x25.0 hex flange

2013-2014.5
Front Rotors diameter 320mm
Rear Rotor diameter (non vented) 272mm ???

2014.5-2016+
Front Rotor diameter 335mm
Rear Rotor diameter (non vented) 272mm ????

 

[Loki C346]

I'm looking for a few specs on our Focus ST's. I'm hoping someone here know which would save me a trip from heading over to my autoparts store and ordering a set of calipers just for dimension sake.


Front Caliper Piston Dimensions
Rear Caliper Piston Dimensions
Front Caliper Bracket Bolt Size
Rear Caliper Bracket Bolt Size

Front bolts are M14-2.0x35 hex flange, piston is 57mm OD and 51mm overall length. Rear bolts are M10-1.50x25.0 hex flange, cylinder is 38mm OD and 50mm overall length.

 

[JJ91284]

Front bolts are M14-2.0x35 hex flange, piston is 57mm OD and 51mm overall length. Rear bolts are M10-1.50x25.0 hex flange, cylinder is 38mm OD and 50mm overall length.

Thanks, I'll update my original post with your dimensions. I plan to build a brake upgrade setup that utilizes OEM multi piston setups that can be had for cheap. My old car was a grand prix GTP which utilized front corvette C5 calipers on Fbody Brackets, and the rear used grand prix GXP brackets with C5 rear calipers. The setup worked fantastic and was only a couple hundred dollars.

If you can just look over the numbers in my original post and verify that they look alright, I'd appreciate it.

 

[Loki C346]

Looks fine... just to be clear, that's the dimension of the physical cylinder within the caliper that is pushed out by the brake fluid.

 

[JJ91284]

Looks fine... just to be clear, that's the dimension of the physical cylinder within the caliper that is pushed out by the brake fluid.

Yep, that's exactly what I wanted. I needed this to figure out the hydraulics/brake bias of the car with stock calipers. I'll use this to match up multi piston calipers front and rear to get roughly the same piston volume along with front/rear %

 

[HopnDude]

If you're doing what I think you're doing, I'm in!

I took my 94 S10, and upgraded the brakes from the 98+ Jimmy and Blazer. All the S10's and Sonoma's (unless ZR2, aka 4x4 wide body package) had a single piston caliper, and bearings you have to pack every so often. In 98+ the Jimmy and Blazer were going through those and destroying the brakes quicker than usual due to extra weight, that they upgraded the rotor and caliper to accommodate a better braking ability for the added weight. Cost me $110 in junk yard parts, and new bolts from the hardware store for a great front end brake upgrade. Then the rear axle was off a ZR2 and had both a 8.5" rear end, and disk brakes, which was a win win.

In short, if you're trying to find a brake caliper that can provide additional (4 or more piston caliper) braking, that is a direct swap for the ST's factory calipers, and clears the wheels/works with the 12.6 or 13.1 rotor on the same bracket.....I'm game! Keep us posted on your findings.

I'm upgrading from the 12.6" to the 13.1" right now. To my knowledge (what I've read) the 12.6" rotor is External venting only (outer portion of the brake rotor) and the 13.1" is External and Internal venting (outer portion of the brake rotor, and inner portion is open as well - nearest the hub).

 

[JJ91284]

If you're doing what I think you're doing, I'm in!

I took my 94 S10, and upgraded the brakes from the 98+ Jimmy and Blazer. All the S10's and Sonoma's (unless ZR2, aka 4x4 wide body package) had a single piston caliper, and bearings you have to pack every so often. In 98+ the Jimmy and Blazer were going through those and destroying the brakes quicker than usual due to extra weight, that they upgraded the rotor and caliper to accommodate a better braking ability for the added weight. Cost me $110 in junk yard parts, and new bolts from the hardware store for a great front end brake upgrade. Then the rear axle was off a ZR2 and had both a 8.5" rear end, and disk brakes, which was a win win.

In short, if you're trying to find a brake caliper that can provide additional (4 or more piston caliper) braking, that is a direct swap for the ST's factory calipers, and clears the wheels/works with the 12.6 or 13.1 rotor on the same bracket.....I'm game! Keep us posted on your findings.

I'm upgrading from the 12.6" to the 13.1" right now. To my knowledge (what I've read) the 12.6" rotor is External venting only (outer portion of the brake rotor) and the 13.1" is External and Internal venting (outer portion of the brake rotor, and inner portion is open as well - nearest the hub).

Yep, that's exactly what I'm planning on. Currently I'm going to base the design on stock 2014.5+ 13.1 rotors as this allows a lot of people to do relatively stock upgrades. For those with 2013 brake setups like me, it will be time for us to upgrade rotors in the near future anyways so the cost will only be a bit more. The brake upgrade should also still clear peoples 17" winter wheels. I have 17" winter wheels which I hope will still work with the upgrade. I might offer another setup with 14" front rotors but this will probably be less popular and more for autocross guys.

My goal is to have everything ready by end of September. I need to source a 2014.5+ front knuckle with wheel hub along with the rear for mock ups. This way if I need to make a slight spacer/shim it will be easy machine up, which of course will be a last resort.

 

[20focusSTdriver17]

so how did this project ever turn out?