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Discussion Starter · #1 ·
There aren't many features from higher trim levels that I wish my base model had, but one of them is the bigger brake package. I didn't want the torque vectoring setup that squeezes the individual brakes, so that turned me off from getting the sport trim. So I've been waiting patiently for some aftermarket support and I finally came across what I needed. www.r1concepts.com makes some drilled and slotted rotors that fit the sport trim. They also fit the Crosstrek, which happens to have the same caliper and rotor setup as the sport. So after studying parts diagrams, what I thought I needed was a set of 2nd hand Crosstrek calipers (because I'm cheap) and a set of R1concepts sport (or Crosstrek) rotors.







After comparing the calipers for the base model and the sport/Crosstrek, it turns out that the main section of the caliper is the same, just the support bracket is different. This meant I could just replace the support brackets and not have to replace and bleed calipers. This suddenly got much simpler. I even got to reuse my brake pads which have 27,xxx miles on them and a lot left before they're due for replacement.



After digging up some torque specs online, everything bolted up nicely. Just like it should.

My 16" Enkei M52 wheels still have a significant amount of clearance to the new brake setup. The stick-on balance weights have over 1/4" of clearance.



The sport-sized rotors are just slightly smaller than the base model's oversized rotor dust shields, so I didn't have to replace those. 2 of the rotors being removed (one front, one rear) were siezed tight on the hub center bore, but there are nifty little jack screw holes that can be used with some metric bolts to push the rotors free from the hubs. I don't know the exact bolt size. I had some that fint in my spare parts drawers, but I think they are either 6mm or 8mm. There also were some rubber plugs from the stock rear rotors that had to be transferred to the new rear rotors. The plugs are for access to the internal parking brake friction shoes.

Overall, I'm very pleased with the results. It's a relatively cheap upgrade and took me about 3hrs to do rotors on all of the wheels, including my cleanup time.

 

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Discussion Starter · #4 ·
Only the front are larger. The rotor prices were low enough that I just decided I'd do a matched set for front and rear.
 

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Looks like you used the 11.4" front rotors which are from the Sport and Premium models. I didn't know that they used the same caliper mounts, which makes a conversion like this so much easier than on some cars.

FWIW, I put drilled and slotted rotors on my Scion, and after a few hundred miles, I noticed that they made a LOT more noise on hard stops!
 

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Discussion Starter · #6 ·
Base, limited, and premium all have the 10.9" front rotors. Only the sport (and Crosstrek) come with the 11.6" front rotors.

I've had cross drilled front rotors on my 240z for many years. They've never gotten any louder that the solid rotors. So far, these on the Impreza haven't either. I'll update if I notice a change but I'm not expecting one. In my experience, changes in braking noise over time have been attributed to choice of caliper pads.
 

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There aren't many features from higher trim levels that I wish my base model had, but one of them is the bigger brake package. I didn't want the torque vectoring setup that squeezes the individual brakes, so that turned me off from getting the sport trim. So I've been waiting patiently for some aftermarket support and I finally came across what I needed. www.r1concepts.com makes some drilled and slotted rotors that fit the sport trim. They also fit the Crosstrek, which happens to have the same caliper and rotor setup as the sport. So after studying parts diagrams, what I thought I needed was a set of 2nd hand Crosstrek calipers (because I'm cheap) and a set of R1concepts sport (or Crosstrek) rotors.







After comparing the calipers for the base model and the sport/Crosstrek, it turns out that the main section of the caliper is the same, just the support bracket is different. This meant I could just replace the support brackets and not have to replace and bleed calipers. This suddenly got much simpler. I even got to reuse my brake pads which have 27,xxx miles on them and a lot left before they're due for replacement.



After digging up some torque specs online, everything bolted up nicely. Just like it should.

My 16" Enkei M52 wheels still have a significant amount of clearance to the new brake setup. The stick-on balance weights have over 1/4" of clearance.



The sport-sized rotors are just slightly smaller than the base model's oversized rotor dust shields, so I didn't have to replace those. 2 of the rotors being removed (one front, one rear) were siezed tight on the hub center bore, but there are nifty little jack screw holes that can be used with some metric bolts to push the rotors free from the hubs. I don't know the exact bolt size. I had some that fint in my spare parts drawers, but I think they are either 6mm or 8mm. There also were some rubber plugs from the stock rear rotors that had to be transferred to the new rear rotors. The plugs are for access to the internal parking brake friction shoes.

Overall, I'm very pleased with the results. It's a relatively cheap upgrade and took me about 3hrs to do rotors on all of the wheels, including my cleanup time.

Would you be able to send me a link for those torque specs please, I've searched with no luck. Thanks.
 

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Discussion Starter · #9 ·
I looked up torque specs on other Subarus and compared torque specs. They have had the same mount bolts and specs for many years.
 

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BEWARE if you live where roadsalt is used in the winter. Rotors with 'slots' or 'holes' in them simply provide more surface-area for rust to grow on the rotors. After 2-3 winters, the rust spreads out onto the braking-surface.

I do not consider shortened rotor lifespan an "upgrade" :)
 

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Discussion Starter · #11 ·
The point of this swap was to get the larger diameter rotors in the front. This upgrade could also have been done with non-drilled, non-slotted rotors.

One thing though about the rotors I did use. The zinc plating is doing a nice job of keeping them looking new. The OEM rotors had surface rust everywhere the brake pads didn't touch, including the vented disk openings. It will be interesting to see how this zinc galvanization holds up to brake rotor heat cycles.
 

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Either way, solid, slotted, drilled or simply in there looking at it... seem to me like a brake flush is always warranted, yes?

The fact you've shown the upgrade can be done without opening the lines up to air is a BIG plus, i agree, and this thread is an excellent resource. But personally, even if one doesn't do a bleed or flush when they get their new car, once it's a year old it's beyond time... to me. It doesn't take much fluid contamination to compromise optimum braking... even with stock parts. But new pads and rotors... on a car a couple years old?



:) It's a cold Monday morning, good natured nudge,
 

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Discussion Starter · #13 ·
Annual brake system fluid flushes? Holy recreational car maintenance Bat Man!
 

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BEWARE if you live where roadsalt is used in the winter. Rotors with 'slots' or 'holes' in them simply provide more surface-area for rust to grow on the rotors. After 2-3 winters, the rust spreads out onto the braking-surface.

I do not consider shortened rotor lifespan an "upgrade" :)
This is why you buy a quality rotor. I live northern pa and ran power stop drilled/slotted rotors for years and never had an issue.


Sent from my iPhone using Tapatalk
 

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There aren't many features from higher trim levels that I wish my base model had, but one of them is the bigger brake package. I didn't want the torque vectoring setup that squeezes the individual brakes, so that turned me off from getting the sport trim. So I've been waiting patiently for some aftermarket support and I finally came across what I needed. www.r1concepts.com makes some drilled and slotted rotors that fit the sport trim. They also fit the Crosstrek, which happens to have the same caliper and rotor setup as the sport. So after studying parts diagrams, what I thought I needed was a set of 2nd hand Crosstrek calipers (because I'm cheap) and a set of R1concepts sport (or Crosstrek) rotors.







After comparing the calipers for the base model and the sport/Crosstrek, it turns out that the main section of the caliper is the same, just the support bracket is different. This meant I could just replace the support brackets and not have to replace and bleed calipers. This suddenly got much simpler. I even got to reuse my brake pads which have 27,xxx miles on them and a lot left before they're due for replacement.



After digging up some torque specs online, everything bolted up nicely. Just like it should.

My 16" Enkei M52 wheels still have a significant amount of clearance to the new brake setup. The stick-on balance weights have over 1/4" of clearance.



The sport-sized rotors are just slightly smaller than the base model's oversized rotor dust shields, so I didn't have to replace those. 2 of the rotors being removed (one front, one rear) were siezed tight on the hub center bore, but there are nifty little jack screw holes that can be used with some metric bolts to push the rotors free from the hubs. I don't know the exact bolt size. I had some that fint in my spare parts drawers, but I think they are either 6mm or 8mm. There also were some rubber plugs from the stock rear rotors that had to be transferred to the new rear rotors. The plugs are for access to the internal parking brake friction shoes.

Overall, I'm very pleased with the results. It's a relatively cheap upgrade and took me about 3hrs to do rotors on all of the wheels, including my cleanup time.

Would you be able to give me the part numbers for the bigger front caliper brackets? The parts department at Subaru says they can't tell which one is which between the sport and non sport.
 

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Discussion Starter · #18 ·
All 2018+ Crosstreks use the same as the Sport. I don't have the part number handy, but Crosstrek parts list will be right too.
 

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Discussion Starter · #19 ·
Crosstrek and Sport have the 26225FL020 caliper support bracket. It says same part for left and right (I got mine used with left and right calipers attached). Subaru parts outlet has them discount priced at $52 each. Dealerships sometimes do price matching.
 

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Discussion Starter · #20 ·
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