BMW 3 Series (G28) Big Brake Kit Upgrade / TTSPORT Classic 8703
The BMW 3 Series has been the benchmark sport sedan since 1975, and the current G28 keeps that reputation alive with a 2.0L turbo four that puts down 190 kW and 400 Nm in 330 trim — good for a 5.9-second 0-100 km/h run with xDrive and the 8-speed Steptronic gearbox. A car that quick deserves brakes that match its pace, so this G28 owner stepped up to a TTSPORT 8703 six-piston big brake kit.
The kit went in behind the car's stock 19-inch wheels — TT8703 monobloc calipers, 380x34mm high-carbon heat-treated drilled rotors, and stainless steel brake lines, all sized to bolt into the factory brake package without changing wheel fitment.
Vehicle & Kit Specs
| Item | Specification |
|---|---|
| Vehicle | BMW 3 Series, G28 chassis, 19-inch factory wheels |
| Front caliper | TTSPORT 8703 six-piston, one-piece cast aluminum monobloc caliper |
| Front rotor | TTSPORT 380x34mm high-carbon, heat-treated, drilled rotor |
| Lines | TTSPORT stainless steel brake lines |
Why It Works
- The TT8703 caliper is cast as a single aluminum piece rather than bolted together from two halves. That one-piece bridge handles clamping force with less flex than a two-piece design, which is why the pedal felt noticeably firmer after the swap.
- Heat-treating the 380x34mm rotor at 600°C boosts its strength and wear resistance, which helps the disc resist the warping that repeated hard stops can cause on a stock rotor.
- The drilled rotor face increases the friction coefficient against the pad and sheds heat faster, giving more consistent bite as brake temperatures climb.
- The whole setup was built to clear this car's factory 19-inch wheels, so the owner got the upgrade without changing wheel fitment.
After the install, the driver reported a firmer pedal and noticeably sharper control on the road — the kind of change you feel the first time you get on the brakes hard.
Installation Gallery
Frequently Asked Questions
What wheel size does the TTSPORT 8703 kit fit on this G28 3 Series?
What's included in the TTSPORT 8703 big brake kit for the G28?
Does the drilled rotor help with heat resistance?
Need fitment confirmation? Choose the closest TTSPORT series or send your vehicle, wheel size, and intended use before ordering.