Millway Motorsport BMW E46 M3 Rear Caliper Adapter/Carrier Brackets – Porsche Boxster S (986/987) / Brembo Rear Caliper Conversion – Bolt-On Mounting Plates – Retains OEM Stock Rear Discs/Rotors – E46 Rear Brake Upgrade Kit

Give your BMW M3 E46 the rear stopping power it deserves with this Millway Motorsport rear caliper mounting solution. These precision steel hanger brackets allow you to bolt Porsche Boxster S rear calipers, and comparable Porsche rear units, onto the E46 M3 while keeping your factory rear discs. It is a clean, bolt-on conversion that looks OEM, delivers excellent pedal feel, and opens up a wider choice of pad compounds for fast road and track use.

If you have been searching for a rear Brembo swap for E46 M3, Porsche rear caliper carriers for E46, or an E46 M3 rear brake conversion that retains stock rotors, this is the tidy, proven setup. We run these brackets on our own builds and our customers consistently report spot on fitment, solid feedback, and dependable performance lap after lap.

Why this kit

• Direct bolt-up caliper carriers to mount Porsche Boxster S rear calipers to the E46 M3 rear upright
• Retains OEM rear discs and handbrake arrangement for a cost-effective upgrade
• CNC machined steel construction for accuracy, rigidity, and durability
• Supplied with 12.9 high tensile fasteners for a secure, confidence-inspiring fit
• Lightweight design without compromising strength
• Sold per axle set

Best for

• Rear brake improvement on BMW M3 E46 without changing discs
• Porsche rear Brembo conversion on the E46 platform
• Track day and fast road cars seeking better pad options and caliper stability
• OEM-like appearance with motorsport-grade hardware

Compatibility

Designed for BMW E46 M3 rear axle using Porsche Boxster S rear calipers and similar Porsche rear calipers. Uses your original E46 M3 rear discs.

What you receive

• Millway Motorsport rear caliper mounting brackets for BMW M3 E46
• 12.9 grade mounting hardware
• Pair for one rear axle

Fitting

Professional fitting is recommended. For expert installation, contact MJ Modifications in Warwickshire for a quote: info@mjmodifications.co.uk.

Notes

• Calipers, pads, and discs are not included
• Torque all hardware to the manufacturer specification and use appropriate thread locking where required

Trusted by enthusiasts

We have installed and used these brackets ourselves. Feedback from our customers highlights straightforward fitment, consistent rear brake balance, and a reliable, bolt-on solution that integrates perfectly with factory components.

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