When selecting a crankshaft for a high performance application, many vehicle owners question what type of steel they should use for their crankshaft. Obviously different steels have different qualities, but the strength of their composition largely depends on the heat treating process that was used after the crankshaft was produced. Although heat treating is beyond the scope of this page, we will look at the most common grades of steel used for forged and billet crankshafts below.
Those who own performance engines, and want to gain the most horsepower possible, often seek the services of an automotive machine shop that provides a crankshaft knife edging service. Normally reserved for racing applications, a knife edged crankshaft can help the engine produce more horsepower. Below we will look at how the knife edging process is completed and the benefits it offers.
As you can tell by the picture to your left, a knife edged crankshaft refers to the shape of the crankshaft’s counterweights. Removing this material and bringing it to a sharp edge does a couple of things. First, knife edging can often remove pounds of weight from a V8 crankshaft. Even some V6 crankshafts will realize a significant weight reduction when the counterweights have been knife edged. Less weight equates to a rotating assembly that spins with less resistance, and this in itself is responsible for some gains in horsepower. Knife edging also reduces friction, which is explained below. Continue reading