R680A

R680A — front 6-piston forged-aluminium caliper from TAVRUS for B-, C- and D-class cars. OVERVIEW R680A is a large 6-piston front caliper for B-, C- and D-class vehicles with a one-piece forged (monobloc) body of lightweight skeletonized design. The body is forged from aluminium alloy: forging delivers high rigidity, tensile strength, toughness and material density. Compared with cast aluminium calipers, body rigidity is about 50% higher; this reduces the risk of caliper failure in service. The built-in double oil seal (instead of ordinary external dust boots) makes the brake feel and reaction more precise. After anodizing and vacuum coating (CVD) the colour is locked in: the coating does not crack or peel and gives the caliper a metallic sheen and vivid colour. One of the calipers developed and mass-produced in-house: its lightweight design provides a more linear pedal feel. Fitting improves the look of the wheel and lets the car handle everything from daily driving to the track. HIGHLIGHTS • One-piece forged (monobloc) 6-piston caliper of in-house design with a lightweight skeletonized construction. • Lightweight design combined with a more linear pedal feel. • After rigorous multi-stage testing in various conditions, performance is about 45% above the factory caliper. • With high-performance pads it confidently handles intense driving in various conditions, including mountain roads and the track. CALIPER SPECIFICATIONS • Weight: 2670 g • Piston area: 50.41 cm² • Piston diameter: 26.96 mm × 2 / 31.66 mm × 2 / 38.1 mm × 2 • Brake disc diameter: Ø355 mm / Ø380 mm / Ø400 mm • Brake disc thickness: max 34 mm / min 32 mm • Caliper dimensions: D177 × H72.75 × W305 mm • Oil inlet thread: M10×1 • Mounting hole centre distance: 210 mm • Mounting hole offset: 42 mm • Mounting hole diameter: 12 mm • Distance from mounting plane to the top of the disc: 61.8 mm BRAKE DISC • Friction surface width: Ø355 × 32 — 59 mm; Ø380 × 34 — 59 mm; Ø400 × 34 — 59 mm • Ventilation: Ø355 × 32 — 72 curved ducts, 7 slots, PCD 233 mm; Ø380 × 34 — 84 curved ducts, 7 slots, PCD 258 mm; Ø400 × 34 — 84 curved ducts, 7 slots, PCD 278 mm • Heat treatment: 580 °C heating / 120 °C cooling, cycled for 72 h • Mounting hole diameter: Ø9.1 mm • Centring ring: Ø203 mm (355×32, petal step 2.5 mm); Ø238 mm (380×34, 1.5 mm); Ø258 mm (400×34, 1.5 mm) • Surface treatment: iron phosphating, ground friction surface • Disc standard: GG20HC BRAKE PADS • Model: R680A • Thickness: 25 mm • Friction surface width: 54 mm • Friction block area: 70.22 cm² × 2 pads per caliper • Compound: F500 (standard) / F600 (street, optional) / S750 (street & track, optional) / R900 (track, optional) / S800 (for carbon-ceramic discs, optional) QUALITY CONTROL • Forged body tensile strength: Qb ≥ 320 MPa • Body hardness: HV ≥ 400 • Low-pressure seal test: 0.4 MPa air, hold 5 s, pressure drop ≤ 100 Pa • High-pressure seal test: 12 MPa air, hold 5 s, pressure drop ≤ 0.2 MPa • Appearance: anodized surface free of damage, uniform colour and gloss • Ultra-high pressure test: sampled calipers withstand 30 MPa oil pressure without failure • Other characteristics per QC/T592.