Keyed 4 Pin Crank Hub M3 / M4 / M2C S55 Designed by Maximum PSI

WHAT IS A “KEYED CRANK HUB UPGRADE” AND WHY DO I NEED IT?
There are thousands of reported cases on the internet of "spun crank hubs" on stock and modified cars with the S55 engine. The keyed crank hub upgrade is a replacement of your stock crank hub unit with a unit that has four “keys” or “pins” for which 4 holes are drilled into the S55 crankshaft so that upon installation of the crankshaft bolt the new keyed crank hub can be locked into place permanently without a chance of relative rotation to the crankshaft. This allows further insurance against the chance of the crank hub “slipping” or “spinning” and un-syncing the relative angles between the crankshaft and camshafts (this can mean engine failure which will cost upwards of $20,000 to replace or at the very least leave you stranded and un-driveable until the crank hub is replaced and engine is retimed). This SCH failure has been seen on both modified and stock S55 engines. If you are modifying your car, tracking your car, or even driving spiritedly, then upgrading your crank hub is highly recommended.

Watch our YouTube video above for a full demonstration! Please note, YouTube video displays 2 pin hub for reference.

UPGRADED 4 PIN DESIGN!
Welcome the new and improved 4 pin design! As can be seen in the photo above, the latest revision of the crank hub has been upgraded to 4 pins as opposed to the previous design which had 2. The new design is meant only to further decrease the chance of failure and not by any means was it changed due to any failures.

As it stands there is still a 100% success rate of the previous 2 piece 2 pin crank hub since we took over on the distribution of them, however that doesn't mean there wasn't room for improvement. The engineering / machining facility that is in charge of the manufacturing of this product was given the opportunity to improve on the previous design and did so based on their extensive knowledge of materials science and machining.

As mentioned above, based on the physical characteristics of this system, this new 4 pin design will only further guarantee the integrity of the product and ultimately offer our customers an even greater peace of mind!

KIT INCLUDES

• Two Piece Keyed Crank Hub
• OEM Crank Bolt
• Specialty Drill Bit
• Drill Fixture Tool
• Drill Fixture Bolt

INSTALLATION
We suggest that this Crank Hub Kit ONLY be installed by a highly qualified technician. BMW specialty tools are required in order to complete this procedure.

Improper installation may cause irreversible engine damage.

Local Southern California customers please contact us today to schedule your appointment (800) 438-2808 (all in house installations come with a 1 year / 10,000 mile warranty).

APPLICATIONS

• BMW F80 M3 (2015 +)
• BMW F82 M4 (2015 +)
• BMW F82 M2 Competition (2019 +)
• The items in this kit are compiled specifically for the BMW S55 engine and therefore will fit any other unlisted models that use a BMW S55 engine