4 Hydraulic Pistons + EPB Actuator
Four 28 mm hydraulic pistons drive the pads, paired with a 27 mm EPB actuator piston that retains the factory electronic parking brake.
Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 14 - Jul 19
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
Evolution EP4S Rear Wheel 4-Piston Big Brake KitEvolution Series Rear Axle EPB Compatible BBK Evolution EP4S Rear Big Brake Kit with Electronic Parking Brake The Evolution EP4S is a rear axle big brake kit built for modern platforms that still require an electronic parking brake. Four hydraulic service pistons handle stopping work, while a dedicated EPB actuator piston preserves factory parking brake function so you get real rear axle thermal capacity without losing OE convenience. Why Builders
Evolution Series · Rear Axle · EPB-Compatible BBK
Evolution EP4S Rear Big Brake Kit with Electronic Parking Brake
The Evolution EP4S is a rear-axle big brake kit built for modern platforms that still require an electronic parking brake. Four hydraulic service pistons handle stopping work, while a dedicated EPB actuator piston preserves factory parking-brake function — so you get real rear-axle thermal capacity without losing OE convenience.
Why Builders Choose the EP4S
Two-Piece Forged Aluminum Body
The EP4S caliper is machined from a two-piece forged aluminum body for high stiffness at low weight, 4.50 kg per caliper without pads.
Rear-Axle Thermal Capacity
Two-piece rotor assemblies with CNC-machined aluminum hats keep unsprung and rotating mass in check while delivering the heat capacity a performance rear axle needs.
Matched Iron or CCB Pads
Iron rotors are paired with a street/track pad rated 0–600 °C with average μ ≈ 0.38. Carbon-ceramic rotors ship with a CCB-specific pad rated 0–700 °C with average μ ≈ 0.45.
Technical Specifications & Kit Options
| Brake Caliper | ||
|---|---|---|
| Series | Evolution Series | |
| Model / Application | EP4S | |
| Axle Position | Rear | |
| Piston Count | 4 hydraulic + 1 EPB actuator | |
| Piston Type | Two-piece heat-insulated, dust boots + EPB actuator | |
| Piston Diameter | 28 mm × 4 / 27 mm × 1 | |
| Total Piston Area | 30.4 cm² per caliper | |
| Caliper Dimensions | 278 × 202 × 93 mm (L×W×H) | |
| Manufacturing Process | Two-piece forged aluminum body | |
| Net Weight | 4.50 kg per caliper (no pads) | |
| Surface Finish | High-temperature gloss coating | |
| Recommended Wheel Size | 18 in or larger | |
| Recommended Rotor Size | Ø345–380 mm × 28 mm | |
| Brake Rotor Options | ||
| Rotor Option | Iron Rotor | Carbon-Ceramic Rotor |
| Rotor Material | Heat-treated high-carbon iron | Carbon-ceramic composite |
| Axle Position | Rear | Rear |
| Rotor Dimensions | Ø345 / 355 / 380 × 28 mm | Ø380 × 28 mm |
| Construction | Two-piece, internally vented | Two-piece, internally vented |
| Rotor Mounting | Fixed or floating, size/application dependent | Floating |
| Directional Design | Yes — left/right specific | Yes — left/right specific |
| Rotor Face Pattern | Curved slot / Grain slot / Wave slot / Drilled & slotted | Cross-drilled |
| Brake Pad Options | ||
| Pad Option | Iron Rotor Pad | CCB Rotor Pad |
| Compatible Rotor Material | Iron rotors only | Carbon-ceramic rotors only |
| Operating Temperature Range | 0–600 °C | 0–700 °C |
| Average Friction Coefficient | avg μ ≈ 0.38 | avg μ ≈ 0.45 |
| Lines | ||
| Brake Line Construction | Three-layer reinforced | |
| Brake Line Material | PTFE liner / SUS304 braid / PVC outer sheath | |
| Brake Line Fittings | Vehicle-specific fittings | |
| Brackets | ||
| Rotor Hat Manufacturing Process | CNC-machined | |
| Rotor Hat Material | High-strength aluminum alloy | |
| Caliper Bracket Manufacturing Process | CNC-machined | |
| Caliper Bracket Material | Carbon steel | |
| Caliper Mounting Type | Radial mount with vehicle-specific brackets | |
| Fitment & Installation | ||
| Minimum Spoke Clearance | 97 mm | |
| Recommended Wheel Size | 18 in or larger | |
| EPB Interface | Vehicle-specific; final EPB interface details vary by application | |
| Bedding-In Procedure | Required before aggressive use | |
Iron rotors are paired with a street/track pad rated 0–600 °C with average μ ≈ 0.38. Carbon-ceramic rotors ship with a CCB-specific pad rated 0–700 °C with average μ ≈ 0.45 — strong initial bite with linear modulation deeper into the pedal.
Package List
Calipers ×2
2× EP4S 4-piston rear calipers with integrated EPB actuator.
Brake Pads
Performance brake pads matched to rotor material for both calipers.
Brake Rotors ×2
2× two-piece rotors in your selected size and face pattern.
Caliper Brackets ×2
CNC carbon-steel mounting brackets.
Rotor Hats ×2
CNC aluminum rotor hats.
Brake Hoses ×2
Stainless-steel braided brake lines with vehicle-specific fittings.
Mounting hardware is included.
Will It Fit? Your 3-Step Check
This is a platform-adapted rear big brake kit. Final brackets, brake-line fittings, rotor diameter, and EPB interface details vary by vehicle and must be confirmed before ordering.
1. Wheel Diameter
18-inch wheels or larger are required.
2. Spoke Clearance
Minimum spoke clearance is 97 mm. Verify your wheel offset and internal spoke geometry before purchase.
3. Vehicle Model
Brackets, brake-line fittings, rotor size, and EPB interface are confirmed per application.
Contact us with your year/make/model/trim and wheel spec so we can validate fitment before you order.
Installation & Break-In
- Final brackets, brake-line fittings, rotor diameter, and EPB interface details vary by vehicle and must be confirmed before ordering.
- The EP4S retains the factory electronic parking brake when correctly interfaced with your vehicle.
- A bedding-in procedure is required before aggressive use.
- Follow the supplied procedure to transfer pad material evenly to the rotor and stabilize friction levels.
Frequently Asked Questions
Does the EP4S keep my factory electronic parking brake?
Yes. The caliper includes a dedicated EPB actuator piston (27 mm) in addition to the four hydraulic service pistons, so the OE electronic parking brake function is retained when correctly interfaced with your vehicle.
What rotor sizes are available?
Iron rotors are offered in Ø345, 355, and 380 mm × 28 mm. A carbon-ceramic composite option is available in Ø380 × 28 mm. All are two-piece, internally vented, and directional (left/right specific).
What wheel size do I need?
18 inches or larger, with a minimum 97 mm spoke clearance. Wheel internal geometry varies even within the same diameter — confirm clearance against the caliper envelope (278 × 202 × 93 mm) before ordering.
Will this fit my car directly?
The EP4S is a platform-adapted kit. Brackets, brake-line fittings, rotor size, and EPB interface are confirmed per application. Contact us with your year/make/model/trim and wheel spec so we can validate fitment before you order.
How does the EP4S improve braking performance?
It replaces a smaller OE rear caliper and rotor with a stiffer four-piston forged caliper and a larger two-piece vented rotor. The result is greater thermal capacity, more consistent rear-axle contribution, and more stable pedal feel under repeated heavy stops.
Which pad compound ships with the kit?
Iron rotors ship with a 0–600 °C street/track pad (avg μ ≈ 0.38). Carbon-ceramic rotors ship with a CCB-specific pad rated 0–700 °C (avg μ ≈ 0.45). Both are matched to the rotor material and should never be cross-used.
Ready to spec your EP4S build?
Need fitment confirmation, a custom rotor face pattern, or a matched front big brake kit?
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.2 ★★★★★
Based on 2345 reviews
Sort
Product Reviews
★★★★★ 5
Love tem, so comfortable
Size: 11 Plus, Color: Microfiber - Colors May Vary
Love these!!!!!! Tired of under pants riding up, get these. They're so comfortable I don't even know I'm wearing them. I freaking love them!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 20, 2026
★★★★★ 4
Okay
Size: 7, Color: Cotton Stretch - Colors May Vary
They fit good. The middle does ride up when walking. They cover good and go about mid thigh.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 4, 2026
★★★★★ 5
The cutest backpack!
Size: One Size, Color: Lilac Ditsy Floral
I was worried maybe this backpack wouldn’t last us the school year. I was pleasantly surprised as we are nearing the end of the year. It’s the most adorable pink and purple bag! It is on the smaller side but we’ve still been able to fit a normal sized folder in it plus her extra clothes and snacks with some room still.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 24, 2026
★★★★★ 5
VERY NICE BUT TOO BIG
Size: One Size, Color: Lilac Ditsy Floral
Let me start by saying its a great product and looked to be made very well. I did have to return it though because it was far too big for my child. Other than size being 1 size fits all with no dimensions given and, yes, somewhat smaller than other backpacks (for adults) it seemed to be a decent backpack. Too bad we couldn't use it but if you have a older kid would would great for.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 5, 2025
★★★★★ 3
Size too small.
Size: One Size, Color: Beige Leopard
It was too small. Couldn’t fit my everyday planner in it.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on December 29, 2025