The stock K24 crank is a high quality forged piece and we use it. We chamfered the oiling holes, deburred it, then sent it out for mangaflux to check for cracks, balancing, micro polishing the journals then WPC treatment.
As with many of our builds, we used Kings XP rod and main bearings. We have had extremely good luck with these bearings. The XP bearing uses Kings P-Max black tri-metal construction a steel backing is covered with a hard intermediate layer with a high tin and copper content for superior load-bearing capacity. This is covered with an overlay with a 2-3% copper content which is harder than typical for excellent load-bearing capacity. This intermediate layer and overlay result in a bearing with 24% more load capacity and 17% more fatigue resistance than its competitors.
King XP bearings are coated with their pMaxKote. pMaxKote is a ceramic nanoparticle enhanced polymer coating. The coating provides increased wear and seizing resistance while increasing the bearing’s load capacity. We have torn down some long term race motors that have run this coating and were amazed to find the bearings looking like new. The upper main bearings that are grooved have King’s U-Groove oil groove design, this design has a deeper but more narrow oil channel that allows for good oil distribution while giving more bearing surface area for better load-bearing capacity.
King Bearings use an eccentric profile for a better hydrodynamic oil wedge formation. The bearings also use King’s radial lock method to provide a better press fit for more spin resistance and better heat transfer from the bearings surface without bearing surface distortion in the area where the shells come together. We used King Part Numbers MB5259XPC STD and MB5259XPC.026 for the main bearings and CR4542XPC STD and CR4542XPC .026 for the rod bearings.
While we were sending stuff out for WPC treatment, we sent out the oil pump gear as well. This improves this critical part’s strength and reduces friction to reduce oil heating while pumping.