Ford Small-Block Engine Parts Interchange. George Reid
enthusiasts have long called the 221, 260, 289, and 302-ci engines “Windsor” V-8s. However, the only true “Windsor” engine is the 351-ci raised-deck small-block Ford introduced in 1969 as a response to the cubic-inch race going on in Detroit. Even though the 221/260/289/302 engines were manufactured at Ford’s Cleveland engine plant, there are crossovers that require clarification. Not all 289/302 blocks and heads were cast at the Cleveland foundry. Quite a few were also cast at Windsor with a “WF” in the casting. Cleveland castings received a circled “CF.” Some blocks were devoid of any kind of foundry identification, which makes it tricky to identify them.
To achieve the 351’s displacement, Ford had to raise the 302’s deck 1.28 inches to accommodate the 3.500-inch stroke. Bore size remained the same at 4.000 inches. To improve power, smoothness, and reliability, Ford gave the 351W a different firing order than the 221, 260, 289, and 302 engines. Beginning in 1982, the 302 (5.0L) received the 351W’s firing order for the same reasons with the flat-tappet Marine camshaft. Ford insiders from the period tell me that the 5.0L engine was switched to the 351W’s firing order to more equally distribute stresses across the crankshaft.
The 351W employs a thicker walls around cylinder bores and main webs. Interchangeability with other small-block Fords is considerable, enabling all kinds of swaps. The 351W, for example, has the same six-bolt bellhousing bolt pattern as the 289/302 six-bolt blocks, making it possible to swap this engine into 289/302-powered vehicles. The 351W also accepts 289/302 engine mounts. Cylinder head bolt and bore patterns make head swaps straightforward.
Ford raised the 302 block deck 1.28 inches to conceive the 351-ci Windsor V-8 for 1969, which was available in 4V versions only in 1969.
This is the 351W-4V V-8 for 1969 with a C9OX experimental cast-aluminum dual-plane intake manifold and Autolite 4300 4V carburetor.
Where it becomes challenging is 351W cooling passages between intake manifold and cylinder heads. Early 351W cylinder heads have dogleg cooling passages, making it necessary to modify intake manifold gaskets and passages. The 351W’s cylinder heads are a great budget horsepower swap for 289 and 302 engines because they employ the same block deck patterns. These desirable heads have larger ports, valves, and chambers. Larger chambers have reduced compression ratio. Keep this in mind anytime you’re considering a head swap.
Because the 351W has larger (1/2 inch) head bolts than the 289/302 (7/16 inch), you need bolt spacers, available from Summit Racing Equipment and other aftermarket sources such as ARP, which enable you to install 351W heads on a 289/302 using the 289/302 head bolts.
The 351W “3M” nodular iron crankshaft has larger main and rod journals than the 289/302 along with a longer stroke. This crank had longer connecting rods (5.956 inches) than you find inside the 289/302. For 1969 it was the only 351W-4V engine produced with 10.7:1 compression. The 351W-2V engine had a more modest compression ratio of 9.5:1.
For one year only (1995), Ford’s Special Vehicle Team (SVT) fitted the Mustang Cobra R with a 300-horse 351-ci (5.8L) V-8, the only year SN-95 Mustangs were fitted with a 351 and only in the SVT Cobra R.
The 351W-4V was equipped with the Autolite 4300 4-barrel carburetor while the 351W-2V was fitted with the Autolite 2100 2-barrel. Ford never produced a high-performance 351W V-8 prior to the Lightning F-150 with the 5.8L High Output V-8. All were fitted with flat-tappet hydraulic camshafts.
Ford’s legendary race-bred Boss 302 engine remains one of the most significant high-performance power plants in the company’s history. It was a world beater and symbolic of the end of the classic muscle car era. The Boss 302 engine was introduced just as Ford decided to get out of racing. Think of the Boss 302 engine as a wonderful act of desperation because the 1968 302 Tunnel Port was such a miserable flop for Ford.
In theory, the Tunnel Port cylinder head was a great idea, making a whopping 450 hp at 8,000 rpm. The problem was that racers needed to push it to nearly 9,000 rpm to make checkered-flag power, scattering the engines all over racetracks from coast to coast. Because this problem was epidemic, Ford engineers had to think fast and arrive at a solution everyone could live with to salvage a hard-won reputation for winning.
We will probably never know which came first, the Cleveland engine or the Cleveland cylinder head. But we do know Ford’s engineers took the 351C-4V poly-angle-valve wedge head and used it on the Boss 302-ci engine to achieve peak horsepower in the 6,500- to 7,500-rpm range instead of a rod-snapping 9,000. This was possible thanks to the 351C having the same bore spacing as the 289/302/351W. All it took was cooling passage modifications to these Cleveland castings (because the 351C has a dry intake manifold and the Boss 302 has a wet one), which was easy in production.
Boss 302 engines had 1.73:1 rocker arms mounted on screw-in studs with adjustable fulcrums. All had flat-tappet high-performance mechanical camshafts.
The Boss 302 block began life as the 302 Tunnel Port block with a “C8FE” casting number, four-bolt main caps, heavier webbing, forged steel 3.00-inch stroke crankshaft, heavy-duty connecting rods (actually “C3OE” 289 High Performance rod forgings with broached 3/8-inch bolts and beefy shoulders), and TRW forged aluminum “pop-up” pistons designed for Cleveland wedge chambers. Compression was 11.0:1.
Don’t be surprised to find a “C8FE” block in an early 1969 Boss 302 Mustang because quite a few made it into production cars. The rest were surplus castings left over from the Tunnel Port days that made it into the Ford Muscle Parts program and dealer pipelines.
Other Boss 302 features included a dual-advance dual-point distributor that was a Boss 302 exclusive. On top, the Boss 302 had a 780-cfm Holley 4160 4-barrel carburetor. From 1969 through early 1970, Boss 302 engines were fitted with chrome-plated, stamped steel valvecovers. Early in the 1970 model year, Ford went to cast-aluminum valvecovers. Ram-air was not available on the Boss 302 until the 1970 model year. All 1969 Boss 302 Mustangs were non-ram-air. Ignition systems included a dual-point dual-advance/retard Autolite distributor.
There has been a lot of debate through the years as to why Ford produced two engine families displacing 351 ci: the 351W and 335-series 351C. The 351 Cleveland is a small-block V-8 with the attitude of a big-block thanks to very innovative engineering features. The 351C-4V engine does its best work at high RPM thanks to large intake ports and tight wedge chambers offering good quench. This engine suffers from inadequate exhaust scavenging despite its huge intake ports. Exhaust ports tend to be restrictive considering the generous flow going in. You can do some port work on the exhaust side and gain flow, but don’t expect much improvement.
The 351C-4V has never been very productive with low-end torque because its 4-barrel cylinder heads were designed primarily for high-RPM horsepower and not low-RPM torque. This begs the question why Ford put this engine in car lines not intended for high-RPM use, such as Galaxie, LTD, Fairlane, and Torino. The 351C had a brief four-year production life (1970–1974 in North America). It was never practical for Ford to produce two engine families in North America employing the same displacement. The 335-series Cleveland was more costly to produce than the 351W, which sealed its doom as a mainstream engine in North America.
Ford’s