fitted with the cast crank with 2.870-inch stroke devoid of any markings that first year. It was also fitted with the C2OE connecting rod until mid-1963 when it received the stronger C3AE forging. The 260’s cylinder heads had larger 53-cc chambers with the same 1.590/1.390-inch valve sizing of the 221. Valvestem size also stood at 0.310 inch, just like the 221’s.
The 260 was available only with Autolite 2100 2-barrel carburetion with automatic choke. Both the 221 and 260 were mild-mannered mills at 8.7:1 compression with cast pistons for use with regular leaded fuels of the era. Carroll Shelby launched two-seat Cobra production with the 260-ci small-block topped with a Cobra high-rise manifold and Holley carburetion.
The 260 was also short-lived with production ending in 1964.
Ford increased bore size to 4.000 inches to conceive the 289 in 1963 while staying with the small-block’s original 2.870-inch stroke and cast crank. The 289 can easily be viewed as one of Ford’s most successful engines thanks to an incredible performance history at LeMans, Indianapolis, Sebring, Daytona, and dozens of other racing venues around the world.
This is a 1965 289-4V V-8 in gold over black, premium fuel, with California emissions closed-crankcase ventilation in a Mustang. All small-blocks originally delivered to a California sales district had closed-crankcase ventilation.
The 1965 289 High Performance V-8 yielded 271 hp at 6,000 rpm. It was unavailable with automatic transmission until 1966 in the United States. Most were fitted with the cast-iron Ford Top Loader 4-speed transmission.
You cannot take the 260’s 3.800-inch bores to 4.000 inches to make it a 289 because cylinder wall thickness becomes compromised. You have to begin with a 289 or 302 block. The 289 block is a thicker casting designed for larger 4.000-inch bores. The same can be said for the 302 block, with its extended cylinder skirts (extended by .015 inch), which came later in 1968. In fact, the 302 block first showed up in the 1967 model year stuffed full of 289 internals: the 1M crank with 2.870-inch stroke with C3AE rods and cast pistons.
There are many misconceptions about the 289. It is time to set the record straight. All 289 cylinder heads, including High Performance, have the same port, valve, and chamber dimensions. Intake valves are 1.780 inches. Exhaust valves are 1.450 inches.
What makes the 289 High Performance head “high performance”? The valvespring pockets for stability along with screw-in rocker arm studs engineered to withstand high RPM. Otherwise, 289 High Performance heads aren’t any different than standard 289 castings. If you desire the features of 289 High Performance heads without the price, you can upgrade the 2V/4V head to screw-in rocker arm studs with pushrod guide plates and valvespring cups. You get the same result for less money.
In the 289’s first year, 1963, two basic engines were available: a 2-barrel version with Autolite 2100 carburetion as in the 221 and 260, and the 289 High Performance with Autolite 4100 4-barrel automatic choke carburetion and mechanical tappets, 9.0:1 compression, cast-iron exhaust headers with automatic choke heat stove, and 289 High Performance–specific heads.
In 1964, Ford added a third 289 to the mix. It had 4-barrel carburetion and the same compression ratio as the 2-barrel available in Mustangs only (D engine code).
California emission standards manifested themselves two ways in 1964: closed crankcase ventilation coupled with the use of a positive crankcase ventilation (PCV) valve, the latter also used on most 49-state cars. There’s no rhyme or reason as to how these engines were equipped and distributed, besides the California emissions closed crankcase ventilation system. Some 289 engines were fitted with PCV valves while others were fitted with a draft tube. Some 1964 289 engines were fitted with timing cover oil filler tubes, while most were located in the driver-side valvecover.
This is Ford’s 289 High Performance V-8 with closed crankcase ventilation California emissions package and a PCV valve (not visible). Some Hi-Po engines were clad with the “Cobra Powered” valvecover sticker. It has yet to be proved whether this was added at the factory or a dealer parts counter.
Beginning in the 1966 model year, all Ford engines were clad in Ford Corporate Blue, which was a move to identify them as Ford engines. This is a 1966 289 produced prior to May 1966 with traditional small-block Ford valvecovers.
Combustion chamber sizes in 1963–1964 ranged from 52.6 to 55.6 cc for all 289 engines. Chamber size depended upon the casting. All 1963–1964 289 engines had five-bolt bellhousing blocks just like the 221 and 260.
Mid-Year Changes
Important upgrades in the 289 occurred for the 1965 model year beginning in August 1964. The most obvious was a block casting change from a five-bolt bellhousing pattern to a six-bolt to improve noise, vibration, and harshness. Aside from this important change, the 289 remained essentially the same, with the base 289-2V engine retaining 52.6- to 55.6-cc combustion chambers and dished pistons to keep compression at 9.0:1. Valve sizes remained the same.
The 289-4V engine went from sharing dished pistons and the same compression ratio to 10.0:1 and flat-top pistons for 1965. All pistons, flat-top and dished alike, had valve reliefs. The 289 High Performance V-8 remained virtually unchanged aside from the six-bolt bellhousing block and a higher compression ratio.
As of May 2, 1966, Ford went to a rail-style rocker arm and pent-roof (flat-top) valve covers on 289-2V/4V engines, which continued through the 1967 model year. This 289-4V engine has California emissions closed crank-case ventilation.
The 289 didn’t change for 1966 aside from engine color. California emission standards became tougher for 1966, calling for not only closed crankcase ventilation, but also Ford’s Thermactor air-injection pump system to help completely burn hydrocarbon emissions.
Effective May 2, 1966, 289-2V and 4V engines received important cylinder head and valvetrain changes: rail-style rocker arms, longer valvestems, revised cylinder head castings, and pent-roof (flat-top) valvecovers. The pent-roof-style valvecovers were in production through the 1967 model year.
One subtle change during the 1966 model year was the short-term use of a finned timing cover through early 1967. Although the 289 High Performance V-8 never employed rail-style rocker arms, it did use pent-roof valvecovers with a chrome finish and High Performance open-element air cleaner for 1967.
Production of the 289 ended in 1968.
For 1968, Ford went to a pent-roof “Power By Ford” valvecover as well as a redesigned air cleaner assembly for 289/302 engines, all with closed crankcase ventilation for 50-state use. The 289/302 also were equipped with Improved Combustion (IMCO) with a coolant temperature–activated spark timing vacuum control valve. This is the “J” code 302-4V V-8 with Autolite 4300 carburetion in a 1968 Mustang.
Shown is a 1970 302-2V V-8 with the same basic small-block