BMW 5 Series Big Brake Kit Upgrade / TTSPORT Classic 8703
A long-wheelbase BMW 5 Series is a comfortable, well-equipped daily driver, but the stock brakes on a car this size and this quick can start to feel overworked once you lean on them — soft pedal, long travel, and not much reserve when it matters. This owner went with a full front-and-rear TTSPORT big brake kit, including a TTSPORT electronic parking brake (EPB) caliper out back so the factory parking brake still works as it should.
The build went front six-piston, rear four-piston plus EPB — a setup sized for a mid-to-large sedan that still needs to keep its factory parking brake function. Everything was fitted behind the car's existing 20-inch wheels.
Vehicle & Kit Specs
| Item | Specification |
|---|---|
| Vehicle | BMW 5 Series (long-wheelbase), fitted with 20-inch wheels |
| Front caliper | TTSPORT TT8703 monobloc-cast six-piston caliper |
| Front rotor | 405x34mm high-carbon heat-treated drilled rotor |
| Rear caliper | TTSPORT TT6411 four-piston caliper |
| Rear rotor | 380x32mm high-carbon heat-treated drilled rotor |
| Parking brake | TTSPORT single-piston electronic parking brake (EPB) caliper, mounted alongside the TT6411 |
Why It Works
The TT8703 front caliper is a one-piece (monobloc) casting rather than a bolted two-piece body, which cuts down on flex under hard braking — that's what gives the pedal a firmer, more predictable feel instead of the sponginess of the stock setup. It ships with dust boots on the pistons to keep maintenance simple.
- The 405x34mm front and 380x32mm rear drilled rotors add mass and surface area over stock, which helps manage heat and delays fade under repeated hard stops.
- The drilled pattern on both rotors improves airflow around the rotor face, helping shed heat faster than a plain solid disc.
- Splitting the rear caliper into a four-piston unit for service braking and a separate single-piston EPB motor for parking keeps the factory electronic parking brake fully functional after the swap.
- The whole kit was sized to clear the car's existing 20-inch wheels, so this build didn't need a wheel change to run the bigger rotors.
Installation Gallery
Frequently Asked Questions
What calipers does this BMW 5 Series kit use?
How does the parking brake work with the rear big brake kit?
What rotor sizes come with this kit?
What wheel size was this BMW 5 Series running with the kit installed?
Need fitment confirmation? Choose the closest TTSPORT series or send your vehicle, wheel size, and intended use before ordering.