Here's How Ford's 302 Small Block V8 Evolved Into The 5.0 And Defined High Performance For 30 Years
The Ford small block V8 engine's greatest champion was the 302. Dubbed the 5.0 later in life as the industry moved from cubic inches to liters in describing displacement, it was the workhorse of the automaker's line-up, pulling duty in everything from sports cars to vans to pickup trucks.
The 302 arrived on the scene at the end of the 1960s as a high performance option for the Mustang, but it not only had its roots deeper in Ford's past, it would have a future impact that extended well beyond the pony car, too.
The Windsor family of Ford V8s debuted in 1961 as a replacement for the Y-block series. Over the next few years the engine's displacement was aggressively increased, moving from 221 to 260 to 289 cubic inches, with the latter gaining a foothold in a long list of intermediate and even full-size Ford cars and trucks (including the Mustang, the Torino, the Fairmount, the Galaxie, and the Falcon).
The 302 cubic inch version of the Windsor small block arrived in 1968, stroking out the 289 to 3.00 inches but retaining the same pistons (by way of shortened connecting rods). This provided for good parts compatibility between the 289 and the 302, which featured up to 230 horsepower and 310 lb-ft of torque (with a four-barrel carburetor installed). The standard motor was given a compression ratio of 9.5:1, and it came with hydraulic lifters, but the Shelby GT350 added a unique high-rise intake as well as larger valves and a higher compression ratio to boost output to 315 hp and 333 lb-ft of torque.
The following year Ford also offered the Boss 302, which share only its displacement with the Windsor motor (as it included 4-bolt mains instead of 2-bolt, its own casting, and completely different cylinder heads). With solid lifters and many parts borrowed from the K-Code or 'Hi-Po' version of its 289 cubic inch predecessor, the Boss produced 290 hp and 290 lb-ft of torque and was the centerpiece of Ford's Trans-Am racing program for both the Mustang and the Mercury Cougar. The engine lasted until the 1970 model year.
The Small Block That Stayed
Ford continued to enlarge the Windsor, adding an inch of deck height and increasing the stroke to 3.5 inches for a 351 cubic inch version of the engine, but unlike past small blocks the 302 didn't leave the scene after its bigger sibling arrived. Instead, it stuck around as the base eight-cylinder option in much the same range of vehicles it had debuted in, becoming one of the most versatile options in the Ford portfolio.
Of course, the 302 small block wasn't immune to the same pressures that were facing every other engine during the dark years ahead. In 1971 the four-barrel option was no longer offered with the motor, and by 1972 compression has been reduced to 9.0:1, dropping horsepower to 210. The net horsepower ratings and further EPA smog choking had the venerable engine down to a measly 122 hp at the mid-point of the '70s, and it hovered between there and 140 horses the next few years before briefly disappearing from the order sheet for 1980-81 in favor of a poorly-received, smaller bore version of the same small block.
By that time Ford decided it was time to modernize the Windsor motor, and what better starting point than the old stand-by, the 302, which had been renamed the '5.0' in 1978 as part of America's ill-fated push towards adopting the metric system. The first signs that the 302/5.0 might have new life in it came in 1982 when 'High Output' of 'H.O.' version of the engine arrived under the hood of the Ford Mustang and its Mercury Capri clone.
The motor borrowed its camshaft from the marine version of the 351 (changing its firing order versus the previous 302 incarnation), but compression was still low, checking in at 8.3:1, and the heads from the previous year's 4.2-liter V8 were still in service. Power began to climb for the HO, rising from 157 hp and 240 lb-ft of torque in its first year, jumping to 175 hp in 1983 thanks to the inclusion of a four-barrel carburetor matched with a much-improved dual-plane intake.
Fuel Injection Changes The Game
Primitive throttle-body fuel injection hit the scene in 1984 as an option, knocking power back to 165 ponies, but a series of dramatic improvements to the 5.0 H.O. in 1985 (including hydraulic roller lifters, a new camshaft, improved exhaust, and a fresh set of heads) made the carbureted version of the engine (still on the options list) much more potent.
Horsepower jumped to 210 and torque climbed to 265 lb-ft, and while the move to EFI-only the following year knocked 10 horses from the spec sheet there was no doubt that the 5.0 had finally arrived as a true '80s performance motor.
From that point on, the split between 5.0 H.O. (found in the Mustang/Capri, the Ford Thunderbird and LTD LX, and the Lincoln Mark VII) and standard versions of the 302 (used primarily in trucks, larger passenger cars, and vans) became more definite.
Aside from firing order, the H.O. also embraced SEFI multiport fuel injection for the regular 302 and gained a revised head design in 1987 that helped boost output to 225 hp and 285 lb-ft of torque. A couple of years later mass airflow fuel injection was introduced, which would be the last major change for the H.O. until the inclusion of hypereutectic pistons for 1993.
A Cobra R version of the motor pumped out 240 horses when it was introduced in 1993, thanks to GT-40 heads, a larger throttle body, and a unique aluminum intake manifold.
A Long-Lasting Legacy
By the end of 1995, the Windsor V8 was no longer offered in the Mustang, having been replaced by the 4.6L modular V8 that served as Ford's performance backbone for the next 15 years.
The engine lived on until 2001 under the hood of the Ford Explorer SUV (and its Mercury Mountaineer clone), making these trucks the final bearers of a 30 year Windsor legacy.
Today, both the classic 302 and the modern 5.0 H.O. stand as some of the best-supported V8 engines that the aftermarket has ever seen. Thanks to their sheer ubiquity, there are thousands of shops and hundreds of thousands of high performance parts available for the entire Windsor family of motors.