ECS Tuning 2-Piece Semi-Floating Front Brake Discs/Rotors 325x25mm – Drilled, Grooved/Slotted, Vented, Lightweight – BMW E46 330i 330Ci 330xi & Z4 E85/E86 3.0i 3.0Si – Direct-Fit Pair/Set Fast Road & Track Day

BMW E46 330 and Z4 3.0 front brake upgrade for fast-road and track-day performance. If you want sharper pedal feel, cooler running and reduced fade, these lightweight two-piece front discs deliver a serious step up in stopping power and handling response. Designed as a direct-fit pair for the front axle, they use a semi-floating construction to keep temperatures under control and to resist distortion under hard use.

Why enthusiasts choose this setup

• Real-world performance: noticeably quicker bite, more consistent braking and improved stability under repeated heavy stops.
• Lower unsprung and rotational mass: each disc is around 15.1 lb versus approximately 19.1 lb for OE, which helps turn-in, ride quality and acceleration.
• Outstanding heat management: vented, cross-drilled and slotted rings sweep away gases, water and debris for reliable performance in all weather.
• Warp resistance: the semi-floating interface allows the ring to expand radially under heat, minimising the risk of judder.

Key construction details

• Aluminium hats: CNC machined from 6061 alloy then hard-anodised in matte black for strength and corrosion resistance.
• Grey cast iron rings: favoured for stable friction and durability, engineered to absorb and shed heat rapidly.
• Heat treated rings: increased stiffness and strength for long service life.
• Precision machining: chamfered holes and ball end-mill slots reduce stress risers, with ground friction faces for easy bedding-in.
• Non-friction surfaces painted, including internal vents, to resist salt and grime.

Specifications

• Disc size: 325 x 25 mm
• Front axle, supplied as a matched left and right pair
• Includes stainless rotor set screws to replace rusty originals

Fitment

• BMW E46 330i, 330Ci, 330xi with M54 3.0
• BMW Z4 3.0i and 3.0Si with N52 3.0

Trusted by us and our customers
We have run these on our own builds and customer cars with excellent feedback on bite, modulation and fade resistance. Ideal for spirited road driving and club-level track use when matched with quality pads and fluid.

Professional fitting available
Want them installed correctly first time with proper torque settings and pad bedding guidance? Book fitting with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a quote.

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