Although the General Motors Company is well-known for manufacturing cars and trucks under the Buick, Cadillac, Chevrolet and GMC brands, the automotive manufacturer also produces crate motors. Crate motors, such as the 604, are stand-alone, ready-to-install motors that often are put into vehicles to increase speed and power output, making the vehicles more suitable for racing. As CrateEngineDepot.com notes, General Motors designed the 604 specifically for circle track racing.
The 604 crate motor is a V8, which means it has eight piston chambers -- or cylinders -- and eight corresponding pistons that pump in and out of those cylinders. As with all V8 motors, General Motors arranges the cylinders of the 604 in a V-shape, so that four of the cylinders are on one side of the V and four of the cylinders are on the other side.
Displacement is the total volume or amount of space that the pistons in a motor occupy after firing in a single cycle. A cycle refers to the process of having all of a motor’s pistons fire at once. In general, a motor with a high displacement will be more powerful than a motor with a lower displacement. The 604 crate motor has a displacement of 350 cubic inches, according to CrateEngineDepot.com. This is equal to about 5.7 liters or 5,735 cubic centimeters.
The 604 is able to generate 385 horsepower during normal operation, with a single unit of horsepower equaling 550 ft.-lbs. per second of work. However, as Superior Chevrolet Performance Center points out, when operating at 5,500 rpm, the 604 crate motor can generate 400 horsepower.
Torque refers to the amount of rotational effort -- or twisting force -- that pistons are able to exert on a motor’s crankshaft during the firing process. The 604 is able to achieve its maximum torque-output of 400 ft.-lbs. when operating at 4,500 rpm.
According to Scott’s Machine, the 604’s pistons have flat tops and consist of high-silicon aluminum. Each piston has a diameter of between 3.998 and 3.999 inches and weighs 533 grams or approximately 1.2 lbs.
The 604 crate motor’s crankshaft, which is responsible for converting the up-and-down motion of the pistons into rotational force, consists of cast iron and weighs 55 lbs. The crankshaft has a stroke of 3.48 inches.
The oil pressure of the 604 motor is 40 pounds per square inch at 2,000 rpm.
According to Race-1.com, General Motors recommends running the 604 motor on 92 octane fuel.
The General Motors part number for the 604 crate motor is 88958604.
