When you have a Vortech supercharged 441-cubic inch monster of a small-block Ford pumping out over 1,800-horsepower, your crankshaft of choice had better be able to handle what the Dragzine Project Evil 8.5 is going to put through it.
“All of our small-block Ford Ultra Billet cranks use a Timken 4330VM alloy steel. This particular one also features an additional two center counterweights compared to the typical Ford six counterweights,” Duane Boes, Sales Manager and Tech for Callies Performance Products, explains. “We think the eight counterweight design is a big deal. This adds stability to the center of the crankshaft by countering the “rocking” effect from the opposing journals at each end.”
The team at Bennett Racing Engines assembled the engine. They provided some of the assembly specifics concerning the Callies Crankshaft.
“We use the Callies Ultra Billet for all supercharged engines rated at 1,800-horsepower and above, Jon Bennett explains. “We use the criteria of 2,000-horsepower and above for turbocharged applications.”
The distinctive forging process differentiates the strength levels between a forged steel and billet crankshaft.
A forged crankshaft uses a heated blank of steel which is pounded in a die with a press into the rough crankshaft form. This hammer-style forging pushed the metal grain to flow along the crankshaft shape. This grain structure increases strength by many factors compared to a crankshaft that is cast to shape.
The billet crankshaft begins with a large cylindrical ingot of steel alloy. In the case of the Callies billet crankshaft, the material is a premium grade (Para-Pure) Timken alloy steel. The forging process takes place with the solid cylindrical ingot, and the metal grain flows parallel along the entire length of the solid billet cylinder.
Boes provided more info about the applicable horsepower applications for the Callies billet unit.
“A lot of stress is put on the crankshaft with all of the boosted applications today,” he says. “For a manufacturer to say that this thing will handle a peak horsepower number, it probably will. The problem comes when you factor in hard torque converter pressure and the popping and banging from rev-limiters on the starting line. When you expose a crankshaft to that, it’s trying to go in two directions at once when it comes to torsional stress.”
Boes and Bennett both specified some of the advantages of the crank specs as related to the 4.125-inch stroke. The 441 small-block Ford combination utilizes a 9.50-inch deck that allows for this additional stroke length. Bennett adds, “This stroke is the maximum we can package into this deck height and still have room for a piston that has the needed strength.”
The rod journal sizes in the billet small-block Ford spec sheet can range from 1.850-, 1.888-, to 2.000-, and 2.100-inches. The crankshaft is offered by Callies through KBX Performance and uses the the largest 2.100-inch journal size for the supercharged application.
“One thing we’ve done in particular to the 4340 Ultra Billet crankshaft is the finish. All of the crank surfaces have a specialized surface finish on all our Callies Ultra Billet crankshafts,” Boes adds. “What we call Aero-Shed super finishing is a mirror-like polish treatment that reduces windage and eliminates any stress fractures. With no sharp edges or corners, It’s a well-done piece.”
For applications beyond the typical vibration damper, a dual keyway is machined into the front snout of the Callies crank to handle extra loads such as when driving the Vortech XB-112 billet supercharger.
We asked Bennett about any special bearing clearances with the billet crank, to which he shared, “The clearances would range from .0028- to .0035-inch in a power adder application such as this engine. We will deviate clearances on a normally-aspirated or nitrous engine in some cases due to the use of a lower weight oil used.”