Turner Motorsport Underdrive & Lightweight Accessory Power Pulley Kit for BMW E36 M3/325i, Z3 M, E34 525i (M50 S50 S52) - Alternator/Water Pump/Power Steering + Serpentine Belt - Bosch Alternator Fit

Lightweight Underdrive Accessory Pulley Set for BMW E36 and Z3 M

Unlock free performance with this Turner Motorsport underdrive pulley upgrade designed for Bosch alternator cars. By reducing accessory drag on the serpentine drive system, this kit releases up to 11 bhp for quicker acceleration, sharper throttle response and a more eager revving feel. It is a proven, bolt-on performance enhancement for spirited road driving and track days.

Each component is precision machined from 6061-T6 aluminium and finished in a hard-anodised black coating for exceptional wear resistance in heat and chemical exposure. Strong, light and built to last, these pulleys replace ageing plastic items and deliver reliable gains without compromising the operation of the water pump, alternator or power steering on properly maintained vehicles.

We run this setup on our own cars and customer builds, and feedback has been consistently positive. It is one of the best value-for-money upgrades for the E36 and Z3 M platform if you want more response without touching the engine internals.

Why choose this pulley upgrade

• Reduces parasitic losses for real-world gains in wheel horsepower
• CNC billet aluminium construction with durable hard-anodised finish
• Track and road tested for dependable operation
• Improved drivability and responsiveness across the rev range
• Direct replacement with OEM-like appearance and lighter weight
• Supplied with a fresh accessory belt for correct tension and longevity

What is included

• Turner Motorsport power steering pulley
• Turner Motorsport water pump pulley
• Turner Motorsport alternator pulley for Bosch alternator vehicles
• New accessory drive belt

Essential alternator check

This version fits vehicles equipped with a Bosch alternator only. BMW used both Bosch and Valeo units. Please inspect the label or casting on your alternator to confirm Bosch before ordering. If you have a Valeo alternator, contact us for the correct kit.

Compatibility

Suitable for the following models and engines when fitted with a Bosch alternator:

• BMW E34 525i 2.5 M50
• BMW E36 325i 2.5 M50
• BMW E36 325is 2.5 M50
• BMW E36 325ic 2.5 M50
• BMW E36 M3 3.0 S50
• BMW E36 M3 3.2 S52
• BMW Z3 M Coupe 3.2 S52
• BMW Z3 M Roadster 3.2 S52

Popular search terms

BMW E36 underdrive pulley set, lightweight accessory pulleys, serpentine belt upgrade, alternator pulley, water pump pulley, power steering pulley, M3 E36 performance upgrade, Z3 M tuning, M50 pulley kit, S50 pulley upgrade, S52 accessory drive kit, track day mods, bolt-on power, reduced accessory drag.

Installation and support

Professional fitting available at MJ Modifications in Warwickshire. For a fitting quote or advice on alternator identification, email info@mjmodifications.co.uk. We are happy to help you choose the correct version and get the most from this upgrade.