Introduced in 1968 and used most famously in the Boss Mustang, the Ford 302-cubic-inch engine succeeded the 289-cubic-inch engine. It is also a member of Ford's 90-degree engine family. As Ford casting numbers do not identify engine displacement, identifying this engine requires a combination of visual techniques and casting number referencing. Differentiating the 302 from the 289 calls for some detective work, as these engines are identical in many respects; also, Ford used certain components, such as the block, interchangeably. If the casting numbers do not match with known 302 castings, measuring the stroke (piston travelling distance) becomes necessary.
Count the number of bolts on a valve cover. Fordification lists similar V8 Ford engines with six valve cover bolts as the 289, 302 and 351W engines. To differentiate the 302 from the 351W further, note the lowest thermostat housing bolt on the engine. The bolt on the 302 sits below the water pump; you cannot access it without removing the water pump.
Locate the engine block casting number on the passenger (right) side of the block above the starter. It consists of a combination of nine to 12 numbers and letters divided in up to four sections---"C8AE-6015-B," for example. You may need to remove the starter to access the casting number.
Decode the Ford casting number. Mustang Tek.com decodes the casting number "C8AE-6015-E" as follows: The first letter, "C," represents the decade---the 1960s ("B" indicates the 1950s, "D" indicates the1970s and "E" indicates the 1980s). The first number (in this case, "8") represents the year in the decade indiacted by the letter---1968. The letters that follow provide the vehicle model designation and the engineering component---"A" represents a full-size Ford, and E stands for "engine." The following four digits comprise the Ford part code, with "6015" indicating Ford's engine block designation. Check the remaining code sections against a listing for identification.
Refer to known 302 engine casting numbers such as those noted on Classic Mustang and the listing found on the website Ford Cobra Engine to find the block casting number (see References section).
Remove one of the cylinder heads, if necessary, to measure the engine's stroke. Crank the engine until one of the pistons sits at dead bottom. Measure from the top of the dead-bottom piston to the top of the cylinder wall. According to the website Car Memories, the stroke on a 302 cubic-inch engine measures 3.0028 inches from top to bottom of the cylinder.