Audi A4 (B9) Big Brake Kit Upgrade / TTSPORT Classic 5440
When the Audi A4 B9 first launched, plenty of owners weren't impressed — from the outside it looked like a facelift with new headlights and a sharper beltline, not much else. Sales numbers proved the skeptics wrong, and for the modifying crowd, the B9 turned out to be a platform with real potential, equally happy low and slammed or pushed into wide-body territory. This particular A4 B9 got its brakes addressed with a TTSPORT Classic 5440 forged four-piston caliper, a Dacromet-coated slotted two-piece rotor, and TTSPORT stainless steel brake lines.
The TTSPORT 5440 caliper covers a wide range of applications across entry-level, mid-range, and premium platforms, and it's a common choice for good reason — the two-piece forged aluminum body keeps the material cost and price reasonable while still delivering the durability forged construction is known for.
Vehicle & Kit Specs
The core hardware on this build: a forged four-piston front caliper, a Dacromet-coated slotted rotor, and stainless steel lines, all sized for the A4 B9's front axle.
| Item | Specification |
|---|---|
| Vehicle | Audi A4 (B9) — 17-inch or larger wheels recommended |
| Front caliper | TTSPORT Classic 5440 forged four-piston caliper, two-piece forged-aluminum body |
| Front rotor | TTSPORT Dacromet-coated slotted two-piece rotor |
| Lines | TTSPORT stainless steel brake lines |
Here's the official spec sheet for the TTSPORT 5440 caliper used on this build:
| Brake Caliper | |
|---|---|
| Series | Classic Series |
| Model / Application | 5440 |
| Axle Position | Front |
| Piston Count | 4-piston |
| Piston Type | Star-profile racing pistons without dust boots |
| Piston Diameter | 38 mm × 2 / 41 mm × 2 |
| Caliper Dimensions | L 276 mm × W 138 mm × H 80 mm |
| Total Piston Area | 49.1 cm² per caliper, all pistons combined |
| Manufacturing Process | Two-piece forged aluminum body |
| Net Weight | 2.65 kg per caliper, without pads |
| Surface Finish | High-temperature gloss coating |
| Recommended Wheel Size | 17 in or larger |
| Recommended Rotor Size | Ø330–345 mm × 28 mm |
| Fitment & Installation | |
| Minimum Spoke Clearance (mm) | 86 |
| 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 Dacromet coating on the rotor looks like a thin surface treatment, but the process behind it is more involved than it appears. Beyond making the rotor easier to identify at a glance, the coating protects both the rotor and the pad surface — a combined benefit that adds up to more than the sum of its parts.
- Two-piece forged aluminum caliper body resists flex under hard braking, keeping pedal feel firm and consistent compared to a stock caliper.
- Four star-profile pistons spread clamping force across 49.1 cm² of total piston area, improving pad contact and modulation.
- Sized to clear 17-inch or larger wheels with 86 mm of minimum spoke clearance — no spacers needed on the correct wheel offset.
Installation Gallery
What wheel size do I need to run the TTSPORT 5440 kit on an Audi A4 B9?
What's included in this Audi A4 B9 brake upgrade?
Need fitment confirmation? Choose the closest TTSPORT series or send your vehicle, wheel size, and intended use before ordering.