For an inside look at the Smeding 347 Extreme, click here. The Chevy small-block is undoubtedly the king of racing and hot rodding, but there is little doubt that the Ford small-block beats everything else for a solid second ranking in performance engines. In the mid '60s, the Mustang debut was a success because the high-performance 289 competed on an even footing with the Chevy 283. As the muscle car era progressed, the small-block Ford 289 and 302 fell behind in performance to the larger 327 and 350 Chevrolets. The maximum horsepower of a production line Boss 302 was 290 hp, while there were numerous factory stock small-block Chevys that easily exceeded that number. When Ford eventually upped the displacement of the small-blocks to 351 in 1969, the performance still never exceeded 290 hp.
If the history of the small-block Ford stopped with the end of the first musclecar era, we wouldn't be writing this article. The most relevant history of the small-block Ford begins with the introduction of the redesigned Mustang in 1979. Ford fanatics might remember this as the beginning of the 5.0 Mustang era, and they know this really started the 302 Ford small-block on its way to becoming the popular engine it is today. The '79-and-later 5.0 Mustangs were fast and affordable cars, relatively easy to work on, and responded well to engine modifications. Like the original '64 Mustangs, they helped start a new era of affordable factory performance cars. It seems as though history does tend to repeat itself. Just as the small displacement of the 289 and 302 was easily surpassed by the 327 and 350 small-block Chevys in the '60s, so has the small displacement of the 302 been surpassed in the modern performance era. Again, we are seeing small-block Chevrolets with larger engine displacements dominating the high-performance street scene.
Smeding Performance starts all 347 Extreme engine builds with a brand-new block from Ford. | 
The heart of the 347 is a new Scat Enterprises stroker crankshaft with a 3.4-inch stroke. It is a high-quality piece made from nodular iron. | 
The weak point on any stock 302 is the connecting rod bolts. They measure a mere 5/16 inch in diameter. A stroker crankshaft requires longer connecting rods. The replacement rods are 5.4 inches long and have bolts that are 3/8 inches in diameter. |
Often referred to as the Windsor, after the city where the engines are manufactured, the 302 and 351 are the most common, with the 351 being the largest in the series. While the 351W has the displacement needed to compete with the 350 Chevy, it has certain drawbacks that make it less than ideal for installation into a 5.0 Mustang body, classic Ford truck, or early hot rod. One of the biggest advantages of the 302 Ford is the small outside dimensions. The 302 is 3 inches shorter and 2 inches narrower than the 351W, allowing it to fit into small engine compartments.
To retain the compact 302 dimensions and increase the engine displacement, many aftermarket companies have introduced crankshaft, rod, and piston combinations that will fit within the stock 302 block and increase the engine size to 347 cubic inches. They are called stroker kits. The kit consists of a crankshaft with a 3.4-inch stroke (the stock 302 crankshaft has a 3-inch stroke), eight connecting rods that measure 5.4 inches long (the stock connecting rods measure 5 inches long), eight pistons that measure 4.03 inches in diameter with 1.09 inches of compression height (the stock pistons measure 4 inches in diameter with 1.608 inches of compression height), and a set of 0.03-inch oversize rings. Installing the stroker kit into an engine block basically consists of an engine block rebuild. This requires that the cylinders be bored and honed, and the bearings, rings, gaskets, and seals be replaced.