Have Questions?
-
Genuine Parts
Guaranteed Authentic
-
Modification Specialists
Call for assistance
-
Mod Now, Pay Later
Financing Available
-
Save On Delivery
Free shipping on most orders over $199
MMX Performance S55 / N55 One-Piece High Horsepower 4-Pin Crank Hub Upgrade Kit - BMW M2/M3/M4 (F8x) 2015-2020 / N55 Models 2012-2015
Lease for as low as $/week
The MMX Performance BMW S55 / N55 One-Piece High HP Crank Hub Upgrade Kit (4-Pin) is the ultimate solution for addressing one of the most well-documented failure points in modern BMW turbocharged engines. The factory three-piece crank hub design is known to slip under high load conditions, particularly in tuned or high-horsepower applications, which can result in catastrophic engine damage. MMX has engineered a complete solution that eliminates this risk entirely.
At the core of the kit is a precision CNC-machined, one-piece crank hub manufactured in the UK from billet EN36 steel. This material is heat-treated with a 0.75mm case hardening process, delivering exceptional strength, wear resistance, and long-term durability. Unlike the factory friction-based system, the MMX hub uses a mechanical locking approach with four aerospace-grade dowels that secure the hub directly to the crankshaft, preventing any possibility of slip.
This four-pin design, combined with the single-piece construction, ensures that timing integrity is permanently maintained even under extreme load, high boost, and aggressive driving conditions. When paired with the correct torque procedure using the supplied new OE crank bolt, the result is a significant increase in engine reliability and peace of mind.
To support accurate installation, the MMX kit includes a complete drilling jig system designed specifically for professional installation. This ensures precise alignment when modifying the crankshaft, allowing for safe and repeatable installation. The kit includes a bolt-on drilling guide, location hardware, and a high-speed steel drill bit, providing everything required for proper fitment.
This upgrade is strongly recommended for high-performance vehicles, particularly those exceeding 700 horsepower, where the risk of crank hub slip is significantly increased.
Product Details
- One-piece crank hub design eliminates OEM slip risk
- Four aerospace precision-machined dowels for mechanical locking
- Manufactured from heat-treated billet EN36 steel
- 0.75mm case hardened for maximum durability
- Includes new OE crank bolt
- Complete installation kit with drilling jig and HSS drill bit
- Available with optional capture plate for additional security
- Designed for high-performance and high-horsepower applications
- SKU: MMR20-1004
Vehicle Applications
- BMW F80 M3
- BMW F82 / F83 M4
- BMW F87 M2
- BMW F87 M2 Competition / CS
- BMW F22 / F23 2 Series
- BMW F30 / F31 3 Series
- BMW F32 / F33 4 Series
Notes
- Includes a 1-year manufacturer warranty against defects in materials and workmanship
- Designed and tested in the United Kingdom
Related Products
- MMX S55 / N55 One-Piece Crank Hub Upgrade Kit (Standard Version)
Installation Notes
- Professional installation required due to crankshaft modification
- BMW S55 and N55 crank bolt torque: 100 Nm initial torque plus 270 degrees
Returns may be accepted within 14 days of purchase pending Return Merchandise Authorization (RMA). No returns or cancellations on special order items. All returns will be charged a 20% restocking fee, no exceptions.
To be eligible for a return, your item must be unused and in the same condition that you received it. It must also be in the original packaging. Item must be able to be resold as new.
Several types of goods are exempt from being returned. Hazardous materials, fluids, greases, chemicals, and clothing are not able to return.
Free shipping is available within the lower 48 states for most orders totaling $199 or more. A free shipping option will be available during checkout. This offer is for delivery address in the continental United States and excludes shipments going to Alaska, Hawaii, Military Boxes, and items that require freight shipping.
Processing Time
Patterson Performance stocks a large quantity of items at any given time. Some items may require drop shipping from one of our various distributors. In stock items will ship within 1-2 business days. If you're needing your product quickly, please contact us to verify product availability before placing your order. Orders requiring additional verification (security concerns, incorrect information, etc.) may need additional processing time. Estimated shipping dates are not guaranteed and are subject to change based on inventory levels and manufacturer lead times. Backordered items are shipped immediately once available.
Items ship daily, If the item you ordered is not in stock, a member of our team will contact you via email / phone.
Patterson Performance will only ship to an address that varies from your billing address if payment is made via Paypal or a financing partner.
Patterson Performance ships from multiple warehouses throughout the United States, and sometimes from manufacturers overseas.
You can simply contact us via email / telephone for a live inventory check
Find more information at www.P65Warnings.ca.gov.