A 302 engine has a compression ratio of 10.5:1, a dual point distributor, an aluminum intake manifold and a four-barrel carburetor capable of mixing 780 cubic feet of fuel and air in one minute. The engine has a 290 degree solid lifter cam and a special windage tray in the oil pan. The heads feature steel spring seats, screw-in rocker studs, pushrod guide plates and adjustable rocker arms.
Introduced in 1968, the 302 engine was the first of its kind to use a tunnel port. Huge intake ports and valves surrounded the intake push rods that ran through a small tube in the head. The engine was mildly successful in Trans-Am and Series II racing.
In 1969, Ford renamed the engine as the Boss 302 and improved the design of the head. This improved the heads with canted valves, which, when placed at an angle, allowed more room for larger intake and exhaust valves. A semi-hemispherical combustion chamber was also introduced. The heads used a special block.
The street version of the engine produced 290 horsepower at 5800 revolutions per minute. The engines used for racing produced 470 brake-horsepower at 9,000 revolutions per minute. The engines featured a scraper style windage tray. This tray was attached to four main cap bolts with small threaded holes in their threads.