Ford small block engine: Difference between revisions

| image = Shelby Mustang GT350 engine.jpg

| name = Ford Small Block <ref>{{Cite book |last=Ford Motor Company |year=1989 |title=Ford Parts Catalog 1989 |page=16 |publisher=(Catalog) |id=Ford P/N 77-5289}}</ref>

| aka = Windsor Small Block

| manufacturer = [[Ford Motor Company]]

| type = Ford

| bore = 4.000" (289, 302, 351W) <br> 3.800" (260) <br> 3.680" (255) <br> 3.500" (221)

| stroke = 3.500" (351W) <br> 3.000" (302 & 255) <br> 2.870" (221, 260, 289)

| displacement = {{convert|221|cid|L|abbr=on|sigfig=2}}<br>{{convert|255|cid|L|abbr=on|sigfig=2}}<br>{{convert|260|cid|L|abbr=on|sigfig=2}}<br>{{convert|289|cid|L|abbr=on|sigfig=2}}<br>302 cu in (5.0 L)<br>

{{convert|351|cid|L|abbr=on|sigfig=2}}<br>

| length = 27.50" (302, 351W) <ref group="Note">With 2001 Explorer-style water pump kit (Ford part ''M-8501-A50''). Blocks with older pumps are 1.25" longer.</ref>

| weighthead = Cast =iron

| blockvalvetrain = [[Overhead valve engine|Pushrod = OHV]]<br>Cast iron <br><br>Deckcam, Height:Flat <br> 9.480"tappet ('6962-'7084 351W302, )<br> 9.503" ('7169-'9693 351W) <br> 8.201"-.210"Steel (BOSSroller 302)<br>cam & 8.206"lifters (221,'85-'01 260302, 289,'94-'97 302351W)

| valvetrain fuelsystem = [[Overhead valve engineCarburetor|Pushrod OHVCarbureted]]<br>Cast iron cam, Flat tappet ('621962-'841985 302, '691962-'931987 351W) <br>[[Fuel Steel roller cam & liftersinjection|EFI]] ('851988-'011997 302351W, '941986-'972001 351Wall others)

| power = 140-290

The '''Ford Small Block''' is a series of automobile [[V8 engine]]s built by the [[Ford Motor Company]] beginning in July 1961. The engine was discontinued in new trucks (F-Series) after 1996, and new SUVs (Explorer) after 2001, but remains available for purchase from Ford Racing and Performance Parts as a [[crate engine]]. The "Windsor" designation is an enthusiast designation applied for the family of engines sharing a common basic engine block design (Ford itself never named the engine family). The Windsor designation was adopted to distinguish the {{convert|351|cuin|L|1|abbr=on}} version from the Cleveland [[Ford 335 engine|335-family engine]] that had the same displacement, but a significantly different configuration. The designations of 'Windsor' and 'Cleveland' were derived from the locations of manufacture: Windsor, Ontario and Cleveland, Ohio.

The engine was designed as a successor to the [[Ford Y-block engine]]. Production began in 1961 for installation in the 1962 model year [[Ford Fairlane (Americas)|Ford Fairlane]] and [[Mercury Meteor]]. Originally produced with a displacement of {{convert|221|cuin|L|1|abbr=on}}, it eventually increased to a maximum displacement of {{convert|351|cuin|L|1|abbr=on}}, but was most commonly sold with a displacement of 302 cu in/ 5.0 L , with engines of that displacement offered from 1968 until 2000. From the mid-1970s through the 1990s, the Ford Small Block engine was also marinized for use in smaller recreational boats.

The small-block engine was introduced in the 1962 [[Ford Fairlane (Americas)|Ford Fairlane]]. Displacing {{convert|221|cuin|L|1|abbr=on}}, it was designed to save weight, using thin-wall casting with a block that does not extend below the centerline of the crankshaft. The engine uses a separate aluminum timing chain cover, which differentiates it from the later [[Ford 335 engine|335-series Cleveland]] engines that use an integrated timing cover. All Ford Small Block engines use two-valve-per-cylinder heads, with "2V" and "4V" designations indicating the number of barrels (or venturi) in the [[carburetor]]. The valves are in-line and use straight six-bolt valve covers. Coolant is routed out of the block through the intake manifold.

The design was soon bored to {{convert|260|cuin|L|1|abbr=on}} and again to {{convert|289|cuin|L|1|abbr=on}}, then stroked to {{convert|302|cuin|L|1|abbr=on}}, settling on the most common displacement offered until the engine’s retirement in 2001, nearly 40 years after the basic block design debuted. Two additional displacements were produced during the engine’s history. A {{convert|351|cuin|L|1|abbr=on}} model (stroked from the 302) was offered beginning in 1969 and continuing until 1996. The 351W (so identified to distinguish from the 335-series Cleveland 351C) uses a taller block than the other engines in the series to avoid excessively short connecting rods. And for a brief time in the early 1980s a version with a smaller bore diameter that displaced {{convert|255|cuin|l|0}} was produced as Ford struggled with emissions and fuel economy.

In response to the Chevrolet Camaro's success in the SCCA Trans-Am series, Ford engineers developed a new racing engine from the small block. The first attempt mated a tunnel-port head to a 289 cu in block, but the displacement proved to be too small to deliver the desired power. The next iteration of the engine mated an improved head design to the 302 cu in block, producing the famous "Boss 302". The heads from the Boss 302 became the production heads on the 335-series Cleveland engines, which used the same bore spacing and head bolt configuration as the Windsor engines.

As the 1980s drew to a close, Ford began the design of a new OHC V8 to replace the venerable small block design. The [[Ford Modular engine|Modular 4.6L OHC V8]] debuted in the 1991 [[Lincoln Town Car]], signaling the eventual demise of the OHV Ford Small Block. Through the rest of the decade, Ford gradually shifted V8 applications to the Modular engine, with the Mustang transitioning in 1996. Even as the small block neared the end of its life, development continued, with new cylinder heads introduced for the [[Ford Explorer]] in 1997. Sale in new vehicles ended with the 2001 Ford Explorer, but the engine continues to be offered for sale as a crate engine from Ford Racing and Performance Parts.

The block mount pads and the cylinder wall contour of the 221 and 260 engines changed in January–February 1963 with the introduction of the 289 variant – all 221 and 260 engine blocks up to this time featured 'corrugated wall' construction with two freeze plugs on the side of each bank and engine mount hole pitch distances of 6 inch.

The first engine of this family, introduced for the 1962 model year as an option on the Fairlane and Meteor, had a displacement of 221ci / 3621cc / 3.6 Litres, from a 3.5&nbsp;in (89&nbsp;mm) [[bore (engine)|bore]] and 2.87&nbsp;in (72.9&nbsp;mm) stroke, with wedge [[combustion chamber]]s for excellent breathing. An advanced, compact, thinwall-casting design, it was 24 in wide, 29 in long, and 27.5 in tall (610&nbsp;mm × 737&nbsp;mm × 699&nbsp;mm). It weighed only 470&nbsp;lb (210&nbsp;kg) dry despite its [[cast iron]] construction, making it the lightest and the most compact V8 engine of its type of the era.

The {{convert|289|cuin|L|1|abbr=on}} was also introduced in April 1963. Bore was expanded to {{convert|4.00|in|mm|1|abbr=on}}, becoming the standard bore for most Windsor engines. Stroke remained at 2.87 inches. The 289 weighed 506&nbsp;lb (230&nbsp;kg).

In 1964, an intermediate performance version of the engine was introduced with a four-barrel carburetor and 9.0:1 compression, rated at {{Convert|210|hp|kW|0|abbr=on}} at 4,400&nbsp;rpm and {{convert|300|lbft|Nm|0|abbr=on}} at 2,800&nbsp;rpm.

The engine was an option on the 1964 1/2 [[Ford Mustang]] and was known as the "D-code" from the letter code used to identify the engine in the [[VIN]].<ref>{{cite web|url=http://www.mustangspecs.com/years/64-65.shtml|title=Mustang Specs (1964 1/2 and 1965)|accessdate=March 27, 2014}}</ref><ref>{{cite web|url=http://www.oldride.com/library/1964_mercury_comet.html|title=OldRide 1964 Mercury Comet|accessdate=March 27, 2014}}</ref>

|title = Applications:

|bodystyle = text-align:left;

In the late 1970s an urgent need to meet [[United States Environmental Protection Agency|EPA]] [[Corporate Average Fuel Economy|CAFE]] standards led to the creation of the {{convert|255|cuin|L|1|abbr=on}} version for the 1980 model year, essentially a 302ci with the cylinder bores reduced to 3.68 in (93.5&nbsp;mm). The 302 /5.0 L was to be phased out and the 255/4.2 L was to be an interim engine which would remain until the new V6 was in production - the 255/4.2 L was a quick fix. Rated power (SAE net) was 115-122&nbsp;hp (86-91&nbsp;kW), depending on year and application. Cylinder heads, which were specific to this engine, used smaller combustion chambers and valves, and the intake ports were oval whereas the others were all rectangular. The only externally visible clue was the use of an open-runner intake manifold with a stamped-steel lifter valley cover attached to its underside, reminiscent of previous-generation V8 engines, such as the [[Ford Y-block engine|Y-block]] and the [[Ford MEL engine|MEL]].

It was optional in [[Ford Fox platform|Fox-chassis]] cars including the Mustang and corporate cousin Mercury Capri, Thunderbird, Fairmont, and standard equipment in the [[Ford LTD (North America)|Ford LTD]]. Some variants (i.e. Mercury Grand Marquis) were fitted with a variable-venturi carburetor which were capable of highway fuel economy in excess of 27 MPG. Due to its dismal overall performance the 255 was dropped at the end the 1982 car model-year with 253,000 units manufactured - 302/5.0 L V8 engine production continued and the plans to phase it out were dropped.

The 302 remained a mainstay of various Ford cars and trucks through the late '90s, although it was progressively replaced by the 4.6&nbsp;L Modular engine starting in the early 1990s. The last 302 engine was produced for installation in a production vehicle was at Cleveland Engine Plant #1 in December 2000, as part of a build-ahead to supply Ford of Australia, which installed their last such engine in a new vehicle in August 2002. The 302 is still available as a complete crate motor from Ford Racing Performance Parts.

The block underwent some changes since its inception. In 1971, deck height was extended from 9.480 in to 9.503 in (casting D1AE-6015-DA) to lower the compression ratio to reduce [[Nitrogen oxides|NOx]] emissions without the need to change piston or cylinder-head design. In 1974, a boss was added on the front of the right cylinder bank to mount the air injection pump (casting D4AE-A). In 1974, the oil dipstick tube moved from the timing case to the skirt under the left cylinder bank near the rear of the casting. These details made swapping older blocks from passenger cars with front sump oil pans to more recent rear-sumped [[Ford Fox platform|Mustang]] and [[Ford Panther platform|LTD/Crown Vic]] Ford cars more difficult unless an oil pan had the dipstick mounted therein. In 1984, the rear main seal was changed from a two-piece component to a one-piece design.

The 5.8 L, 351W, was changed during the '90s from speed density to MAF; performance gains were directly affected. Before 1994, the 5.8 L was equipped with speed density. This programmed coding was placed into the vehicle's computer to tell the motor how much air it should be getting, therefore supplying an appropriate amount of fuel. However, if modifications are made to increase air flow, the computer does not provide more fuel, as it is still following the programmed amount of fuel supplied. After 1994, the engine was changed to mass air flow (MAF). This allowed the computer to read how much air the engine was receiving through the help of a sensor in the air intake. Because the computer reads this, it is able to increase the amount of fuel the engine gets when the air flow is increased, thus increasing performance. Without the MAF conversion, the performance of a non-stock to heavily modified 5.8 L, fuel-injected engine will be lacking.

From the late 1960s through the early to mid-1990s, the 351 Windsor had a long history of being marinized by Holman Moody Marine, Redline of Lewiston, ID (now defunct), Pleasure Craft Marine (PCM), and Indmar for use in about every make of recreational boat, including; Correct Craft, Ski Supreme, [[Hydrodyne]] and MasterCraft inboard competition ski boats. The early marinized engines were rated at {{Convert|220|hp|kW|0|abbr=on}}. Most PCM and Indmar marinized 351s were rated at {{Convert|240|hp|kW|0|abbr=on}}. In the early 1990s, a {{Convert|260|hp|kW|0|abbr=on}} version and a high-output version that used GT-40 heads and the Holley 4160 marine carburetor was rated at {{Convert|285|hp|kW|0|abbr=on}}. A few 351 GT-40/HO engines were marinized equipped with throttle-body fuel injection (TBI) and were rated at {{Convert|310|hp|kW|0|abbr=on}}. The marine industry's relationship with the 351W platform ended when Ford was unable or unwilling to compete with GM's production of TBI- and MPI-equipped engines in mass quantity. During that time, the recreational marine community's small-block V8 platform of choice shifted to the 350 cu in (5.7L) GM L31 (Vortec 5700) engine series.

The 'Racing Boss 351' (not to be confused with the Ford 335 engine Cleveland-based [[Ford 335 engine|Boss 351]]) is a crate engine from [[Ford Racing]] Performance Parts. The block was based on the {{convert|351|cuin|cc|abbr=on|0}} Ford Windsor engine, but uses Cleveland sized {{convert|2.75|in|mm|0|abbr=on}} main bearing journals. Deck height choices include {{convert|9.2|in|mm|0|abbr=on}} and {{convert|9.5|in|mm|0|abbr=on}}. Maximum displacements are {{convert|4.25|in|mm|0|abbr=on}} stroke and {{convert|4.125|in|mm|0|abbr=on}} bore. The resulting displacement is up to 454.38 cubic inches (7445.9 cc, or 7.4 L).