Li Auto L9 Big Brake Kit Upgrade / TTSPORT Evolution EB8
To hit a price target, a lot of new-energy vehicles ship with a brake system sized for basic duty — enough for everyday driving but not much reserve for hard, repeated stops. On the Li Auto L9, that shows up as inconsistent, non-linear pedal feel whenever the regenerative braking system hands off to the mechanical brakes, and rear-seat passengers often notice the abruptness before the driver does. This owner swapped in a TTSPORT front-eight/rear-four Evolution Series kit to fix both the shortfall in stopping power and the disjointed pedal transition.
The L9 runs factory 21-inch wheels, which left enough wheel-well room to fit the larger EB8 front calipers and 405mm rotors without any wheel change. The rear axle received the EP4 electromechanical caliper, which keeps the electronic parking brake function intact while adding real four-piston clamping force for driving braking.
Vehicle & Kit Specs
| Item | Specification |
|---|---|
| Vehicle | Li Auto L9, 21-inch factory wheels |
| Front caliper | TTSPORT Evolution EB8, forged eight-piston |
| Front rotor | TTSPORT 405mm high-carbon rotor |
| Rear caliper | TTSPORT EP4, electromechanical four-piston caliper with integrated electronic parking brake |
| Rear rotor | TTSPORT 380mm high-carbon rotor |
| Bracket | Custom vehicle-specific caliper bracket |
| Pads / lines | TTSPORT performance brake pads, stainless steel brake lines |
| Hardware | Brake fluid, mounting bolts, and fixing hardware |
The front EB8 caliper used on this build carries the following official spec sheet:
| Brake Caliper | |
|---|---|
| Series | Evolution Series |
| Model / Application | EB8 |
| Axle Position | Front |
| Piston Count | 8-piston |
| Piston Type | Two-piece heat-insulated pistons with dust boots |
| Piston Diameter | 28 mm × 4 / 32 mm × 4 |
| Caliper Dimensions | L 349 mm × W 166 mm × H 98 mm |
| Total Piston Area | 56.8 cm² per caliper, all pistons combined |
| Manufacturing Process | Two-piece forged aluminum body |
| Net Weight | 4.95 kg per caliper, without pads |
| Surface Finish | High-temperature gloss coating |
| Recommended Wheel Size | 19 in or larger |
| Recommended Rotor Size | Ø380–405 mm × 34 mm |
| Fitment & Installation | |
| Minimum Spoke Clearance (mm) | 107 |
| 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
The EB8 is a forged, two-piece caliper body with a scientifically hollowed-out structure to cut weight without giving up rigidity. Its eight pistons sit in a symmetrical layout across eight pad segments, so clamping force lands evenly across the pad surface — that's what gives the pedal a quick, non-abrupt bite off the top and a firm, linear buildup as you press harder. Two-piece heat-insulated pistons, dust boots, and high-temperature seals keep clamping force consistent as the brakes heat up, and the caliper is rated to pair with either the 380mm or 405mm high-carbon rotor depending on wheel size.
- Symmetrical 8-piston layout for even pad loading and progressive bite
- Two-piece heat-insulated pistons hold clamping force under sustained heat
On the rear, the EP4 builds an electronic parking brake actuator into a four-piston caliper body — the four pistons handle driving brake force, while a separate single-piston section runs the parking brake, so the L9's factory EPB function is preserved. It shares the same symmetrical, hollowed-out design and two-piece heat-insulated pistons as the EB8, which is intentional: pairing an EB8 front with an EP4 rear keeps front-to-rear brake bias balanced instead of overpowering one axle.
Installation Gallery
What TTSPORT calipers and rotors does this Li Auto L9 kit use?
Does the EP4 rear caliper still work with the L9's electronic parking brake?
What size wheels does this installation fit behind?
Need fitment confirmation? Choose the closest TTSPORT series or send your vehicle, wheel size, and intended use before ordering.