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Brakes · Performance Caliper Kit · SKU APX-BK-489

Apex-GT 4-Piston
Brake Kit

Slotted 326mm rotors, 4-piston billet calipers, carbon-ceramic pads, and stainless steel lines. Built for the street, ready for the track. +35% stopping power vs. OEM. 2-year warranty.

Pistons4 Rotor326mm PadsCarbon-ceramic MaterialBillet alu
★★★★★ 4.9 · 412 reviews · Q&A (28)
$489 $549 Save $60
In stock · 84 left · Ships same day
Check fitment for your vehicle
✓ Fits your 2018 Subaru WRX
Or see all compatible vehicles in the Fitment tab below.
Caliper color · APEX Red
Rotor size · 326mm (street/track)
Free shipping on orders over $99 · Same-day shipping · 60-day returns
◆ The Kit

Stop harder.
Last longer.

The Apex-GT 4-piston brake kit is the result of 3 years of R&D with the Subaru Tecnica International (STI) team and 6 podium finishes at the NASA 25 Hours of Thunderhill. It's built for the street, validated on the track, and engineered to outlast the car it's bolted to.

The 4-piston mono-block calipers are CNC-machined from a single billet of 6061-T6 aluminum. The 326mm rotors are slotted (not drilled) to shed water and gas while resisting the stress-cracks that plague drilled rotors on track. The pads are carbon-ceramic for cold bite and fade resistance up to 1,200°F.

Stainless steel braided lines round out the kit. +15% pedal feel over stock. The whole thing weighs 2.4 lbs less per corner than the OEM setup despite the larger rotor.

◆ What's in the box

Everything you need.
Nothing you don't.

2 × 4-piston calipers (front) — APEX Red, pre-bled with DOT-4 fluid.

2 × 326mm slotted rotors (front) — G3000 cast iron, anti-corrosion coated.

1 set carbon-ceramic pads (front axle) — bedded and ready to install.

1 × stainless steel line kit (4 lines) — PTFE core, PVC coated.

Mounting hardware — caliper brackets, banjo bolts, crush washers, thread locker.

Installation guide — 8 pages, with torque specs and bed-in procedure.

★ Winner — SEMA Global Media Award 2025 · Featured in Grassroots Motorsports "Editor's Choice" 2026

◆ Dyno Cell 03 — Burbank, CA

Real data. Real claims.

We don't trust marketing — we trust data. The stopping-distance numbers below come from a series of controlled 60–0 mph tests on the same day, same driver, same vehicle (2018 Subaru WRX), with the only variable being the brake setup. OEM pads + rotors, then again with the Apex-GT kit. Average of 5 runs each.

◆ 60–0 mph stopping distance (ft)
2018 Subaru WRX · 5-run average · 95°F ambient
−18ft
OEM
Apex-GT
◆ Brake fade — 10 consecutive 80–0 stops (ft)
2018 Subaru WRX · 95°F ambient · 2 min cool-down between stops
−0ft fade
Stop 1
Stop 3
Stop 5
Stop 7
Stop 10
Stop 1
Stop 3
Stop 5
Stop 7
Stop 10
OEM (fade increases)
Apex-GT (consistent)
◆ Verified fitments

4 vehicles. 100% guaranteed.

We've validated this kit on the vehicles below. If your vehicle isn't listed, we don't recommend the kit — see related kits at the bottom of the page.

Year Make Model Trim Wheel req. Notes
2015–2024 Subaru WRX / STi All trims 17" or larger —
2017–2023 Honda Civic Type R FK8 / FL5 18" or larger —
2018–2024 Subaru WRX TR Track-focused 18" or larger Requires 6-spoke or larger clearance
2022–2024 Toyota GR Corolla Core / Circuit 18" or larger —
◆ Fitment guarantee
If this kit doesn't fit your vehicle when installed correctly by a certified mechanic, we'll cover return shipping and refund 100% of the purchase price. No restocking fee. No questions. Valid for 60 days from delivery.
◆ DIY-friendly install

2–3 hours. One mechanic.

Installable with basic hand tools in a home garage. No specialty tools required. We strongly recommend a torque wrench for the caliper bracket bolts (see step 4) and a brake bleed kit for the lines (step 6).

01
Lift vehicle & remove front wheels

Use a 2-ton floor jack and jack stands rated for the vehicle's weight. Loosen lug nuts before lifting. Remove both front wheels and set aside.

02
Remove old calipers, rotors, and lines

Unbolt the 2 caliper slide pins (12mm), then the 2 caliper bracket bolts (17mm). Support the caliper with a bungee — don't let it hang from the brake line. Remove the rotor. Unbolt the 4 brake line banjo bolts at the chassis.

03
Install new rotor and caliper bracket

Slide the new 326mm rotor onto the hub. Apply thread locker to the bracket bolts, torque to 95 ft-lbs in a star pattern. Verify rotor spins freely with no rub.

04
Mount calipers with new pads

Insert pads into the caliper — pay attention to orientation (inboard pad has the wear sensor slot). Slide caliper over the rotor, torque slide pins to 25 ft-lbs.

05
Install new stainless steel lines

Route the lines to the chassis mounting points. Use new copper crush washers on both ends of each banjo bolt. Tighten banjo bolts to 14 ft-lbs.

06
Bleed the brake system

Start with the passenger rear, then driver rear, passenger front, driver front. Use DOT-4 fluid. Pump pedal 5 times, hold pressure, open bleed screw, close, repeat until clean fluid comes out. Top off reservoir.

07
Bed-in the pads

Critical step. 5 moderate stops from 50 mph to 20 mph (cooldown between), then 5 harder stops from 60 mph to 10 mph. Drive gently for the first 100 miles to allow pads and rotors to fully mate. Skipping this step will result in uneven pad deposit and reduced performance.

2–3 hrsTime
ModerateDifficulty
Basic hand toolsRequired
2 peopleRecommended
◆ Caliper
Pistons4 (opposed)
Material6061-T6 billet aluminum
Piston sizes38mm × 2, 41mm × 2
FinishType-III hard anodize + powder coat
Weight (each)5.8 lbs
SealsStainless + EPDM
ServiceRebuildable (service kit APX-SK-04)
◆ Rotor & pads
Rotor diameter326mm
Rotor thickness28mm
Rotor materialG3000 cast iron
Rotor finishSlotted · Geomet coated
Pad compoundCarbon-ceramic (CC-Race)
Pad temp range200–1,200°F
Min. wheel size17"
◆ Lines & hardware
LinesStainless braided, PTFE core
Banjo bolts10mm × 1.0, 14 ft-lbs
Caliper bracket boltsM14 × 1.5, 95 ft-lbs
Pad pin torque25 ft-lbs
Fluid specDOT-4 (or DOT-5.1)
4.9
★★★★★
Based on 412 reviews
98% would recommend · 100% fitment confirmed
★★★★★
Stops like a totally different car.

Bought for my 2019 WRX. 4 piston fronts, slotted rotors, stainless lines. Bed-in took about 30 minutes of street driving per the instructions. After 100 miles: no fade after 30 minutes of canyon driving on a 100°F day. Pedal feel is significantly firmer. The red calipers look aggressive as hell behind my 18" wheels. Worth every penny.

JT
James T. · Verified buyer
Reviewed Mar 2026
2019 Subaru WRX · 18" wheels · No issues
★★★★★
Track-day validated.

Ran 6 track days at Laguna Seca and Buttonwillow with these. No fade after 30-minute sessions. Pedal feel stayed consistent. Slotted rotors shed water and pad dust well — no surface rust issues. After 5,000 street miles + 6 track days, rotor wear is minimal, pads at about 60% remaining. Will absolutely buy again.

MR
Marcus R. · Verified buyer
Reviewed Feb 2026
2021 Honda Civic Type R · 19" wheels · 5,000 mi
★★★★★
DIY install in my garage. 2.5 hours.

I've never done brakes before. Followed the install guide step-by-step. Had a buddy help with the brake bleed (definitely need 2 people for that). Everything fit exactly as described. The hardest part was getting the old caliper bolts off — they were torqued on at the factory like they meant it. Soaked them in PB Blaster for an hour. Total time: 2.5 hours including the bed-in drives. Saved myself $400 vs. the shop quote.

DK
David K. · Verified buyer
Reviewed Jan 2026
2018 Subaru WRX · 18" wheels · DIY install
◆ Pairs well with

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