AITO M9 Big Brake Kit Upgrade / TTSPORT Evolution EB10
As EV and hybrid platforms get heavier and quicker off the line, their brakes have to work harder — more battery mass to slow down, more torque to arrest. Most of these vehicles still roll off the line with a 4-piston front caliper, which is fine for daily driving but starts to fade under repeated hard stops. This AITO M9 owner drives aggressively and wanted a setup that could hold a consistent, linear pedal through back-to-back stops — so he went with TTSPORT's Evolution Series front-and-rear kit: EB10 up front, EP4S in the rear.
The finished install: a forged 10-piston EB10 caliper and 420mm high-carbon rotor tucked behind the M9's stock 22-inch wheel, no visual compromise and a noticeably firmer pedal.
Vehicle & Kit Specs
Here's the full breakdown of what went on the car — front and rear axles, both ends built around TTSPORT's Evolution Series hardware.
| Item | Specification |
|---|---|
| Vehicle | AITO M9, 22-inch factory wheels |
| Front caliper | TTSPORT EB10 — forged 10-piston fixed caliper |
| Front rotor | TTSPORT 420mm high-carbon two-piece rotor |
| Rear caliper | TTSPORT EP4S electromechanical caliper — 4 hydraulic pistons plus integrated EPB actuator |
| Rear rotor | TTSPORT 380mm high-carbon rotor |
| Bracket | Custom vehicle-specific front and rear caliper brackets |
| Pads / lines | TTSPORT high-performance brake pads, stainless steel brake lines |
| Hardware | Brake fluid, mounting bolts and fitting hardware |
Below is the official TTSPORT spec sheet for the front EB10 caliper.
| Brake Caliper | |
|---|---|
| Series | Evolution Series |
| Model / Application | EB10 |
| Axle Position | Front |
| Piston Count | 10-piston |
| Piston Type | Two-piece heat-insulated pistons with dust boots |
| Piston Diameter | 28 mm × 4 / 30 mm × 6 |
| Caliper Dimensions | L 415 mm × W 168 mm × H 129 mm |
| Total Piston Area | 67.0 cm² per caliper, all pistons combined |
| Manufacturing Process | Two-piece forged aluminum body |
| Net Weight | 7.50 kg per caliper, without pads |
| Surface Finish | High-temperature gloss coating |
| Recommended Wheel Size | 20 in or larger |
| Recommended Rotor Size | Ø420–440 mm × 40 mm |
| Fitment & Installation | |
| Minimum Spoke Clearance (mm) | 108 (inner-rotor-to-inner-spoke distance) |
| Caliper Mounting Type | Radial mount with vehicle-specific caliper bracket |
| Brake Line Fitting Type | OEM-style chassis-side fitting |
And the official spec sheet for the rear EP4S electromechanical caliper.
| Brake Caliper | |
|---|---|
| Series | Evolution Series |
| Model / Application | EP4S |
| Axle Position | Rear |
| Piston Count | 4 hydraulic pistons + 1 for EPB actuator |
| Piston Type | 2-piece heat-insulated pistons with dust boots + EPB actuator |
| Piston Diameter | 28 mm × 4 / 27 mm × 1 |
| Caliper Dimensions | L 278 mm × W 202 mm × H 93 mm |
| Total Piston Area | 30.4 cm² per caliper, all pistons combined |
| Manufacturing Process | Two-piece forged aluminum body |
| Net Weight | 4.50 kg per caliper, without pads |
| Surface Finish | High-temperature gloss coating |
| Recommended Wheel Size | 18 in or larger |
| Recommended Rotor Size | Ø345–380 mm × 28 mm |
| Fitment & Installation | |
| Minimum Spoke Clearance (mm) | 97 |
| Caliper Mounting Type | Radial mount with vehicle-specific caliper brackets |
| Brake Line Fitting Type | Vehicle-specific fittings; caliper-side and chassis-side fittings vary by application |
Why It Works
Why the EB10 Front Caliper Works
The EB10 is a two-piece forged caliper built for heavy sedans, SUVs, and MPVs — including EVs with extra curb weight to shed. Its 10 pistons are laid out symmetrically so clamping force spreads evenly across the pad, which is what gives it a light, linear pedal at low effort and a hard, confident bite when you really stand on it. TTSPORT reinforces the caliper body with through-caliper ribbing that adds 20-30% more strength versus a conventional design, and the two-piece heat-insulated pistons with high-temp seals and dust boots keep clamping force stable as things heat up — including with carbon-ceramic rotors.
- Forged fixed-caliper body resists flex under hard braking, so pedal travel stays consistent instead of going long and soft after repeated stops.
- Larger 420mm front / 380mm rear rotors add mass and surface area, giving the system more heat capacity before fade sets in.
- The rear EP4S keeps the electronic parking brake fully functional — its dedicated actuator piston handles EPB duty independently of the four service-brake pistons.
- Custom-fit brackets locate both calipers to clear the M9's stock 22-inch wheels with no spacer workarounds.
Installation Gallery
What wheel size does this AITO M9 big brake kit fit?
Does the rear TTSPORT EP4S caliper still work with the electronic parking brake?
What's included in the kit for this install?
Need fitment confirmation? Choose the closest TTSPORT series or send your vehicle, wheel size, and intended use before ordering.