S55 – N55 – N54 Crank Hub Fix for the M3 and M4

S55 - N55 - N54 Crank Hub Fix for the M3 and M4

Lang Racing now offers sale and installation of the recently released Maximum PSI Keyed Crank Hub Kit.

This crank hub kit is specifically designed for BMW S55, N55, and N54 Engines. Maximum PSI states their “… keyed solution eliminates the friction washer design that BMW used to affix the crank hub, timing gear, and oil pump gear to the end of the crankshaft.” We’ve found this to be true in our testing.

– Photos courtesy of Maximum PSI

More on the Crank Hub Kit from Maximum PSI

The original flawed design allows the timing gear to spin independently from the crank, especially when the motor is modified.  Best case scenario the motor needs to be re-timed with new components.  Worst case, the valves contact the pistons requiring a complete overhaul.   Common symptoms are rough running and camshaft angle deviation faults.  We had this issue several times on our shop F80 M3, one of which required valve replacement.  At that point we had this solution machined, and we installed it in our car and a few other test cars last year.  We went from a failure at each event to setting new records at the track and on the dyno.  We have now achieved a best 1/4 mile time of 9.4@149mph, and we just recently made 875whp/805tq on our Dynojet on E85 fuel.

The keyed hub kit includes our keyed crank hub, crank bolt, drill fixture, fixture bolt, and drill bit

Maximum PSI

Crank Hub Kit DIY vs. Professional Installation

As an enthusiasts’ shop, we love hearing about our clients projects. However, even Maximum PSI states that you should have this kit installed by a professional technician. Our technicians have years of experience with all BMW projects and have successfully installed and worked with this kit. If you’re interested in buying/installing they kit on your M car – contact us here, or call us at (949) 667-4397

*Note – due to popularity of this upgrade, manufacturing lead time can cause delays in shipping/installation. Call us to set up installation scheduling based on parts ETA.

Updated With More Crank Hub Installation Photos


  1. Rick Garrison on December 8, 2019 at 1:30 pm

    My 2015 M4 F82 with MT6, has 67k miles. It is my daily driver both ways total of 63 miles a day commuter since new. What is this talk about ” spinning the camshaft”? Blowing the motor up?? The car has been solid w/ no problems. I change the oil every 8000-8500 miles since out of warranty. Is this something to worry about for me? NEVER tracked the car or raced it, really. Hit the Rev limited hand full of times at brake in, if that. What is the deal?

    • Big Jon on December 11, 2019 at 2:07 pm

      Hey Rick, great question. We certainly don’t track every car on the road. However, from what we’ve seen in the shop and discussed with other owners, it’s really rare on stock cars, but more of a concern on tuned cars. I have read some reports on it happening to stock cars, but those are in forums etc so we can’t really confirm.

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