ALTA Lightened Crank Pulley 2% Oversize – MINI Cooper S R53/R52 (SKU: AMP-ENG-520)

Improve boost response and throttle performance with the ALTA 2% Oversize Lightened Crank Pulley, engineered for supercharged MINI Cooper S models. By increasing the crank pulley diameter by 2%, this upgrade boosts supercharger speed, effectively simulating a smaller supercharger pulley without altering the supercharger itself.

Constructed from 6061-T6 billet aluminum, this pulley weighs just 1.0 lb, over 2.3 lbs lighter than stock. The reduction in rotational mass improves engine response, while the added pulley diameter increases boost, enhances belt contact, and reduces wear. Unlike OEM two-piece pulleys that commonly fail, the ALTA LCP is a single-piece design built for long-term durability.

Ideal for use with existing supercharger pulley upgrades, this crank pulley allows a 15% pulley to behave like a 17%, or a 17% to behave like a 19%, all while maintaining charging system integrity and engine balance.

Key Features:

• +2% Oversize Diameter – Increases supercharger speed and effective boost

• Improves Throttle Response – Lightweight design reduces rotational inertia

• 6061-T6 Billet Aluminum – CNC-machined and black anodized for strength and corrosion resistance

• One-Piece Construction – Replaces failure-prone OEM pulley

• Weighs Just 1.0 lb – Over 2.3 lbs lighter than OEM

• Boosts Supercharger Efficiency – Acts as a multiplier for existing pulley upgrades

• No Charging System Issues – Maintains OEM functionality

• 5-Year ALTA Warranty

Vehicle Fitment:

• 2002–2006 MINI Cooper S Hardtop (R53)

• 2004–2008 MINI Cooper S Convertible (R52)

What’s Included:

• (1) ALTA 2% Oversize Lightened Crank Pulley

• Installation Instructions

• ALTA Performance Warranty Info

• ALTA Stickers