Continuing with the development of the crankshaft, work was given to Gord Bush to develop the piece so that it could run as efficient as possible. This included a process called Knife Edging. The large masses of the counterweight create a greater volume of turbulence within the engine as the rotating assembly spins. The counterweights come in contact with your oil and splashes the lubricant within the engine, inducing oxygen and other gasses into the oil. Some say that the gas created from violent turbulence acidifies your oils and shortens the lifespan of your lubricants.
The idea is to remove material from the counterweights such that the counterweight slices through the oil & gases in your engine, much like that of a knife through air, or any other material. By knife edging the crank, it eliminates the need to utilize crank scrapers, which many KA enthusiasts may swear by. Crank scrapers or “Windage tray’s” like the ones made by Xcessive manufacturing are utilized to literally scrape off oils which bond to crankshaft counterweights as they are rotating. With the knife edging process, you no longer need to scrape off the oils as the reduction of crankshaft material allows the oil to spin off at a faster capacity.
The Brian Crower Crankshaft was originally weighed at 45lb. Gord removed upwards of 5lb via the knife edging process. The resultant weight of the piece was approximately 39.8lb, 5.8lb heavier than a stock crankshaft.
These holes are the original locations from which the technicians from BC removed material to balance the Crankshaft.
Here you can see a sectional profile of the crankshaft counterweights. When compared to the OEM piece in my original post, you can see that the mass of material is greatly reduced, yet the counterweight dynamic of the crankshaft still exists.
Here you can see that the oil plug has been placed into the crankshaft. The installation of the plugs required a process called ‘stalking’, from which the installer uses a punch to drive the crankshaft material into the plug to keep it in place.
I promptly requested that Gord complete a full balancing of the Crankshaft after the knife edging was completed. The material was taken off the top profile of the counterweights.
And here is the crankshaft, test fitted into the engine block.
I guess that covers part 3 of the crankshaft posts. The knife edging allowed for just enough clearance with the girdle such that I did not have to weaken the piece by cutting into it. Had the crankshaft not been knife edged, the problem would still exist. At the same time, had the crankshaft not bee knife edged, I would not be able to retain the original piston squirter’s that are mounted on the underside of the engine. They do however need modification and I will cover that in a later post.
Cheers for now! Have a Happy Chinese New Years!