ECS Tuning 2-Piece Lightweight Rear Brake Discs/Rotors 328mm x 20mm - Semi-Floating, Drilled, Slotted/Grooved Performance Set - Fits BMW E46 M3 3.2 & E39 M5 5.0 - Direct Fit OEM Caliper Compatible - Track Day Fast Road Upgrade Pair

Lightweight 2 piece rear brake discs - 328 x 20 - for BMW E46 M3 and BMW E39 M5

Unlock sharper stopping power and confidence with this high quality rear disc set from ECS. Designed for the BMW E46 M3 and BMW E39 M5, these low mass, semi floating, drilled and grooved 328 x 20 mm rear discs deliver rapid heat control, reduced rotational mass and repeatable performance on fast road and track day use. A straight swap for the factory rear discs, engineered to work with the standard calipers and hardware.

We run these on our own cars and customer builds with superb results. Feedback has been consistently positive - stronger initial bite, more stable pedal feel, better fade resistance and a premium finish that lasts. If you are searching for BMW M3 E46 rear discs, BMW M5 E39 rear discs, motorsport style two piece rear rotors, lightweight grooved and drilled rear discs or a direct fit rear brake upgrade for your M car, this set is exactly what you want.

Why enthusiasts choose this setup

• Two piece construction reduces unsprung mass for more responsive braking and improved ride quality
• Semi floating design helps the friction ring expand under heat which supports stability during repeated heavy stops
• Drilled and slotted faces improve gas evacuation, clear water and dust, and help keep pads refreshed for consistent friction
• Excellent heat management to combat brake fade on spirited driving and track sessions
• Direct replacement on the rear axle using OEM style fitment - no extra brackets required

Materials and engineering

• 6061 aluminium rotor hats - hard anodised in matte black for strength and corrosion resistance
• Grey cast iron rings - proven wear characteristics and stable friction, heat treated for durability
• Precision machined slots and chamfered holes to help minimise the risk of stress cracks seen on poorly finished discs
• Non friction areas including internal vents coated to resist salt and corrosion, with ground braking faces for easy bedding in

Key specs

• Position - rear axle
• Size - 328 mm diameter x 20 mm thickness
• Configuration - two piece, semi floating, drilled and slotted, heat treated
• Weight - approximately 14.8 lb per disc vs approximately 15.9 lb for a stock E46 M3 rear disc
• Finish - matte black anodised hat with protective coating on non friction surfaces

What is included

• 1 x pair of ECS two piece lightweight rear discs - 328 x 20
• Stainless rotor set screws to replace rusty factory hardware

Vehicle compatibility

• BMW E46 M3 - S54 3.2
• BMW E39 M5 - S62 5.0

The upgrade that makes a real difference

Looking for an OEM plus rear brake solution that copes with heat, resists fade and keeps pedal feel consistent lap after lap? These ECS rear discs offer the sweet spot for road driven M cars that also see circuit time. Lower mass for faster spin up, strong bite with quality pads, excellent wet weather performance thanks to the slot and hole pattern, and the ability to replace the iron rings in future makes them a smart long term choice.

Professional fitting available

For best results we recommend professional installation and correct pad and disc bedding. MJ Modifications offers fitting at our Warwickshire workshop - request a quote at info@mjmodifications.co.uk.

Notes

• Direct replacement for the rear discs on the listed models
• Suitable for daily road use, fast road and track days

Search friendly terms

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