Steve Magnante's 1001 Mustang Facts. Steve Magnante
there was no difference between the blocks used in 200 (C-code), 225 (A-code), and the K-code 271-hp 289 engines.
53 Another Hi-Po myth claims they inhaled through Holley 4-barrel carburetors. The only 289 Hi-Pos issued with Holley jugs (715 cfm) were found in 1965–1967 Shelby GT350 Mustangs with 4-speed transmissions. By contrast, all 1963–1967 289 Hi-Po 289s (and most 1966 and 1967 automatic equipped GT350s) inhaled through Autolite 4100 series 4-barrel carburetors rated at 460 cfm. Often referred to as the “shoe box” carburetor, the Autolite 4100 debuted in 1957 and was last used on the 1969 Thunderbird 429 engine (not to be confused with the Boss 429).
54 Hi-Po 289-equipped Mustangs all featured a black push/pull knob mounted to the underside of the dashboard below the headlamp switch. It was there to activate the Autolite 4100 series carburetor’s manual choke. A similar Autolite 4100 was used on 225-hp 289 Mustangs (different jetting and accelerator pump settings) but with an automatic (heat controlled) choke assembly, so the manual “choke” knob was absent.
55 To survive the vertical lurch-load imposed by high-RPM clutch dumps, Ford equipped all 289 Hi-Pos with unique cast-iron engine mounts. Much stronger than the stamped steel units used on less potent 289-4 (A-code) and 289/260 2-barrel V-8s, the fortified mount counteracted the violent load induced during dragstrip launches.
56 The early 1965 Mustang option sheet included three engines that were discontinued on August 1, 1964. They were the 101-hp 170-ci 6 (U-code), 164-hp 260 2-barrel V-8 (F-code), and 210-hp 289 4-barrel V-8 (D-code). These engine codes often confuse Mustang newbies. To stir up things further, Ford later revived these Mustang engine codes with the 1967 200-ci 6 (U-code), 1968 302 2-barrel (F-code), and 1980 255 2-barrel (D-code).
57 If the thought of a 101-hp, 170-ci 6 in a ’64½ Mustang coupe sounds lethargic, it could have been worse. The 170 engine family also included a 144-inch version with 90-hp, which (mercifully) was never offered in Mustangs. In fact, the 170 proved to be so tame that Ford made the 200 Mustang’s base engine from August 1, 1964, through 1970. The 200 6 returned as the mid-power engine offering in the 1979 Fox-based Mustang, slotted between the 2.3-liter 4, 2.8-liter V-6, and 5.0-liter V-8.
58 The Ford 144, 170, 200-ci 6-cylinder engine family first appeared in 1960 to motivate Ford’s first post war compact offering (and Mustang’s platform sibling), the Falcon. The block initially used four-main-bearing architecture but thanks to foresight, an upgrade to seven main bearings was easily made for the 1965 model run. Four-bearing 200s appeared in 1963 but were never installed in Mustangs. The seven-main-bearing 200 (and 170) engines are identified by the presence of five core plugs on the side of the block. Four-bearing blocks have three.
59 Today, every new Mustang that Ford builds features overhead cam (OHC) engine architecture. The very first Mustangs with OHC technology were built in the fall of 1964 for sanctioned drag race competition in the NHRA’s 1965 A/Factory Experimental class. Packing Ford’s 600-plus-hp 427 SOHC “Cammer” V-8, only five of these exotic Mustangs were built by Ford’s go-to NASCAR job shop, Holman & Moody in Charlotte, North Carolina. These cars were campaigned by a team of hand-picked drag racers including Gas Ronda, Bill Lawton, Dick Brannan, Les Ritchey, and Jerry Harvey. Another five lightweight Mustangs were constructed at the same time but with 427 wedge power (cam-in-block) due to an initial shortage of the exotic Cammer engines.
Decades before the Modular 4.6 and later Coyote OHC V-8s invaded Mustang engine bays, Ford Factory Experimental drag racers struck fear into the hearts of Mopar 426 Race Hemi drivers with the mighty 427 SOHC Cammer. Fact No. 59 tells more.
60 Ford began its long-running policy of painting Mustang engines Ford Corporate Blue in 1966. The lone exception was seen under the hoods of 252 Shelby GT350s, which retained the 1965 basic black engine paint scheme. That’s because those 252 Shelbys were based on leftover 1965 Mustang platforms. After those 252 cars were completed, all subsequent 1966 Shelby engine blocks and heads were dressed in blue.
If Ford switched to all-blue Mustang engines in 1966, why did 252 1966 GT350 engines still wear all-black paintwork? See Fact No. 60 for the story.
61 Offered initially with only a 4-speed manual transmission, the 271-hp 289 Hi-Po (K-code) was finally made available with an automatic transmission for 1966, much to the satisfaction of would-be customers who wanted the K-code’s 6,500-rpm capability but didn’t want (or know how) to operate a clutch. The K-code High-performance 289 was first offered in 1963 on Fairlane models but never made its way to the Falcon option sheet, despite rumors to the contrary.
62 To ensure reliability when teamed with the rowdy K-code Hi-Po 289, Ford upgraded the C4 Cruise-O-Matic automatic transmission with larger bands and clutches and higher shift-point settings. The heavy-duty C4 also received different gear ratios than the unit installed behind 6s and regular 2- and 4-barrel 289s. Standard C4 ratios were; 2.46, 1.46, 1.0, and 2.20:1 (First, Second, Drive, Reverse). The heavy-duty C4’s ratios were slightly tweaked: 2.40, 1.47, 1.0, and 2.00:1.
63 Those 1966 Hi-Po K-code 289 Mustangers who didn’t want to hassle with a clutch pedal and shifting their own gears paid an extra $216.27 for the privilege. To Ford’s credit, the extra-duty 9-inch rear axle housing and differential remained part of the Hi-Po 289 package, regardless of whether the 4-speed stick or automatic transmission was chosen. Truth be told, the cushioning effect of the C4 automatic transmission’s torque converter would have muted the Hi-Po 289’s 271 hp and 312 ft-lbs of torque, allowing safe use of the standard V-8 rear axle and its smaller 8-inch ring gear.
64 Even though Ford “softened” the Hi-Po 289’s image slightly with the 1966 addition of the C4 automatic, customers who sought the comfort of air conditioning were still out of luck. The Hi-Po’s solid lifters, stiff valvesprings, and superior breathing conspired to allow crankshaft speeds higher than the A/C compressors of the day could handle.
65 Ever wonder how long it took to install Mustang engines on the Dearborn/River Rouge assembly line? Once again, the Martha and the Vandellas 1965 music video “Nowhere to Run” provides the answer: 20 seconds. If you watch frames 104 through 124, you’ll see a fresh A-code 289 4-barrel and 4-speed manual transmission being loaded (by one man) into the engine bay of a Mustang convertible. Watch it on YouTube today.
66 Regardless of engine choice, Ford upsized radiator capacity throughout the 1966 Mustang line. The 6-cylinder cars were increased to 9.5 quarts (from 8.5) and V-8 cars were upgraded to 14.5 quarts (from 14.0).
67 To shed critical nose weight on the 1965 and 1966 A/FX Mustang 427 drag race package cars, lightweight all-aluminum radiators were installed at the Holman & Moody Charlotte, North Carolina, build center. When painted, these units are indistinguishable from standard copper and brass radiators but reveal their dull aluminum finish from top to bottom when stripped. Also offered as over-the-counter service parts, these rare radiators have been seen on vintage Shelby Mustang road racers as well, although Shelby never included them as standard equipment.
68 In 1965 Ford changed the number of bellhousing-to-block attachment bolts from five to six during the 1965 model run. The extra fastener was added to improve structural integrity and reduce NVH factors. Mating 1963, 1964, and certain 1965 289 engine blocks to later 1965 transmissions can be frustrating. All 260 V-8s had the five-bolt configuration.
69 Carroll Shelby must have quietly cursed his initial decision to up-fit each 1965 GT350 with a cast aluminum, deep-sump oil pan bearing the Cobra logos on each side of the sump. Because his conversion plans didn’t include actual engine removal, the pans had to be installed with the engines still in the chassis. This was facilitated by work pits sliced into the floor of Shelby’s 6501 Imperial Highway LAX airport hangar/assembly line where laborers stood in 7-foot-deep troughs under the cars. A messy job, the Cobra oil pan swap involved removing the steering link and engine crossmember and caused much grumbling among employees. By 1967, the aluminum oil pan was dropped entirely. Modern Shelby Mustang restorers freely add the exotic pans to