Audi S3 Big Brake Kit Upgrade / TTSPORT Classic 8703
If you're ranking the quickest gas-powered cars under $45,000, the Audi S3 belongs on that list. The third-generation EA888 makes 290 horsepower and 380 Nm of torque from the factory, and paired with the DQ381 dual-clutch and Quattro all-wheel drive, it hits 0-60 in 4.8 seconds. But Audi bolted on a single-piston floating caliper up front — brake hardware barely different from the regular A3. For a car this quick, that's the weak link, and it's why this S3 got a TTSPORT TT8703 six-piston big brake kit.
The stock setup on an S3 this powerful just isn't matched to the drivetrain. A single-piston floating caliper has one job — clamp from one side and let the caliper slide — which limits pad contact and consistency under hard, repeated braking. This build swaps in a fixed six-piston caliper and a larger rotor to close that gap.
Vehicle & Kit Specs
| Item | Specification |
|---|---|
| Vehicle | Audi S3, 19-inch wheels |
| Front caliper | TTSPORT TT8703 monobloc six-piston fixed caliper, differential-bore pistons |
| Front rotor | 380x34mm high-carbon heat-treated drilled rotor |
| Lines | TTSPORT stainless steel brake lines |
The TT8703 caliper body is cast as a single piece rather than bolted from two halves. That one-piece construction cuts down on flex and vibration under hard braking, which helps both durability and pedal consistency over repeated stops.
Why It Works
- Monobloc casting reduces the flex you get from a two-piece caliper, so pedal feel stays firmer and more consistent under repeated hard stops.
- Six pistons with differential (non-equal) bore diameters keep clamping force applied evenly across the pad, which helps the caliper maintain a linear, predictable bite instead of a sudden grab.
- Stepping up to a 380x34mm rotor adds friction area and mass over the factory disc, and the drilled face helps vent heat and gas buildup during hard, repeated braking.
- The kit was installed and confirmed to clear the S3's stock 19-inch wheels in this build.
Installation Gallery
FAQ
What does the TTSPORT TT8703 kit include for the Audi S3?
Why upgrade the Audi S3's factory brakes?
Will the TT8703 kit clear the Audi S3's stock 19-inch wheels?
Need fitment confirmation? Choose the closest TTSPORT series or send your vehicle, wheel size, and intended use before ordering.