Our engines utilize the factory Rover 4.0 and 4.6 crankshafts. The cranks are ground in order to produce a quality surface for fitment of our US made bearings. This is a very important improvement over the stock engine.
Another important surface of the crank is at the back where the main seal is fitted. Reusing a crankshaft without bringing this surface back to spec will often lead to another expensive repair in the future. It is common practice to just polish this area of the crank and go with it, but we have learned after hundreds of builds that it is best long term to bring this surface back to new during the build process. Proper installation and lubrication of this seal is equally important if the seal is to do its job.