Ford small block engine


The Ford small-block is a series of 90° overhead valve small-block V8 automobile engines manufactured by the Ford Motor Company from July 1961 to December 2000.
Designed as a successor to the Ford Y-block engine, it was first installed in the 1962 model year Ford Fairlane and Mercury Meteor. Originally produced with a displacement of, it eventually increased to with a taller deck height, but was most commonly sold with a displacement of [|302] cubic inches.
The small-block was installed in several of Ford's product lines, including the Ford Mustang, Mercury Cougar, Ford Torino, Ford Granada, Mercury Monarch, Ford LTD, Mercury Marquis, Ford Maverick, Ford Explorer, Mercury Mountaineer, and Ford F-150 truck.
For the 1991 model year, Ford began phasing in the Modular V8 engine to replace the small-block, beginning in late 1990 with the Lincoln Town Car and continuing through the decade. The 2001 Ford Explorer SUV was the last North American installation of the engine, and Ford Australia used it through 2002 in the Falcon and Fairlane.
Although sometimes called the "Windsor" by enthusiasts, Ford never used that designation for the engine line as a whole; it was only adopted well into its run to distinguish the version from the "Cleveland" version of the 335-family engine that had the same displacement but a significantly different configuration, and only ever used to refer to that specific engine. The designations for each were derived from the original locations of manufacture: Windsor, Ontario and Cleveland, Ohio.
, versions of the small-block remain available for purchase from Ford Performance Parts as [|crate engines].

Overview

The small-block V8 engine was introduced in the 1962 Ford Fairlane and Mercury Meteor cars. Displacing, it was designed to save weight, using thin-wall casting for a short-skirt 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-series 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 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 and again to, then stroked to, 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 model was offered from 1969 until 1996. The 351W has a taller deck height 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 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 cubic inch 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 cubic inch 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 small block engines.
As the 1980s drew to a close, Ford began designing a new OHC V8 to replace the small block. The Modular 4.6 L 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. American sales 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.

Design changes

All 221, 260, and 289 engines built from July 1961 through August 1964 used a five-bolt bell housing, with all 221s and 260s being of this configuration, while 289s made after August 1964 changed to the six-bolt pattern – a change made to resolve transmission utilization issues, such as the need for larger-diameter clutches.
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 core plugs on the side of each bank and engine mount hole pitch distances of 6 inch.
All three block variants from this point on featured the straight wall method of construction, three core plugs, and an engine mount hole pitch distance of seven inches. The corrugated wall method of block construction had caused cleaning difficulties in the foundry from day one and a change was phased in.

221

The first version of Ford's modern Ford small block family was called the Fairlane V8,and was introduced for the 1962 model year as an option on the Fairlane and Meteor. It had a displacement of, from a bore and stroke, with wedge combustion chambers for superior breathing, and a two-barrel carburetor. An advanced, compact, thinwall-casting design, it was 24" wide, 29" long, and 27.5" tall. It weighed only dry despite its cast iron construction, making it the lightest and most compact V8 engine of its type of the era.
In stock form, it has a two-barrel carburetor and a compression ratio of 8.7:1, permitting the use of regular rather than premium gasoline. Valve diameters were and . Rated power and torque were at 4,400 rpm and at 2,200 rpm.
The 221 was phased out at the end of May 1963 due to lackluster demand following the mid-'62 introduction of the "Challenger" V8 based on it. About 371,000 had been produced.

255

In the late 1970s, an urgent need to meet EPA CAFE standards led to the creation of the version for the 1980 model year, essentially a 302 with the cylinder bores reduced to. The 302 was to be phased out and the 255 was to be an interim engine which would remain until the new V6 was in production. Rated power was, 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 Y-block and the MEL.
It was optional in Fox-chassis cars including the Mustang and Mercury Capri, Thunderbird, and Fairmont, and was standard equipment in the Ford LTD. Some variants, such as the one used in the Mercury Grand Marquis, were fitted with a variable-venturi carburetor and were capable of highway fuel economy in excess of. Due to its dismal overall performance, the 255 was dropped at the end the 1982 model year with 253,000 units manufactured. 302 production continued and the plans to phase it out were dropped.
Applications:
The 260 was the second version of the Fairlane V8, introduced during the middle of the 1962 model year and given the name Challenger. It used the same block as the 221, and the same two-barrel carburetor, with displacement increased to by expanding its bore to. Compression ratio was raised fractionally to 8.8:1. The engine was slightly heavier than the 221, at. Rated power rose to at 4400 rpm, with a peak torque of at 2200 rpm.
For the 1962 and 1963 model years, the valve head diameters remained the same as the 221, but for the 1964 model year, they were enlarged to and – a manufacturing economy measure so that both 260 and 289 engines could use the same valves. Although the engine breathed better, and was capable of producing marginally more power, rated power was unchanged.
In 1963, the 260 became the base engine on full-sized Ford sedans. Later in the model year, its availability was expanded to the Ford Falcon and Mercury Comet. The early "1964½" Mustang also offered the 260.
Ford ceased production of the 260 at the end of the 1964 model year with approximately 604,000 units having been made.

XHP-260

The special rally version of the Falcon and Comet and early AC Cobra sports cars of 1962 used a high-performance version of the 260 with higher compression, hotter camshaft timing, upgraded connecting rods, valves with larger diameter valve stems, stronger valve springs and a four-barrel carburetor. This engine was rated at 5800 rpm and at 4800 rpm. This engine was termed the HP-260 by Ford and was specifically made for Carroll Shelby. About 100 were produced.

Sunbeam Tiger

The 1964–1966 Sunbeam Tiger Mk I used the 260.
Early 1967 Sunbeam Tiger Mk IIs were fitted the 260 until inventory of that engine ran out, after which it was replaced by the 289 cubic inch V8.

289

The V8 was introduced in April 1963, carrying the Challenger name over from the 260 and replacing it as the base V8 for full-sized Fords.
Bore was expanded to, becoming the standard for most small block Ford engines. Stroke remained at 2.87 inches. Weight was. It retained the 260's two-barrel carburetor, had a slightly lower 8.7:1 compression ratio, and was rated at at 4,400 rpm and at 2,200 rpm.