The story of the Shelby Mustangs start all the way back to its origins of 1962 when Carroll Shelby started Shelby America and Ford delivered a Windsor V8 for the AC Cobra body. The Mustang Shelby’s came about when Lee Lacocca produced the Mustang in 1964 and promised it would be in performance competition. At the time the Mustang had a choice of 2 V6’s and 5 optional V8’s with the K code as its fastest with 271 horsepower. It was not the performance promised for competition, so Lacocca ask Carroll Shelby to make a high performance Mustang.
Generation 1: The Shelby Mustang was built by Shelby American from 1965 to 1967 and by the Ford Motor Company from 1968 to 1970. Carroll Shelby had a falling out with Ford in 1967 which is why the Ford took over design, production and sales for the following 3 years. They retained some of the staff that moved to their new facility over in Illinois but within a year they all left.
The first Shelby Mustang produced was the GT350. It had upgraded intake and exhaust manifolds, carburetor, rear axle and brakes. Shelby built 34 of the road race model GT350R which was designed to compete in the SCCA, which it won a lot. In 1966 they offered an automatic transmission. Many early 1965 cars had the battery relocated to the trunk, which was changed mid-year due to complaints of fumes, and had over-rider traction bars, relocated A-arms, as well as other modifications. A 4-speed Borg-Warner T10 manual was the only transmission available. Dual exhausts exited out the sides via glasspack mufflers (with fourteen cars being equipped with rear-exiting exhausts to meet state regulations for sales in certain areas). For this one year, the GT350 also had special 130 mph (210 km/h)-rated Goodyear “Blue Dot” tires, named for the prominent blue dot on each sidewall. The 1965 GT350 had a full-size spare tire mounted in place of rear seats, making it a 2-seat-only vehicle (to qualify as a “sports car” under SCCA regulations), and rode on either silver-painted steel wheels or special cast-magnesium center “Cragar Shelby” 15-inch rims with chromed center caps marked with a stylized “CS”. Total 1965 model year production was 562 units.
For a promotional idea they came up with an idea to have Hertz Rental Agency rent out Shelby Mustangs. They persuaded Hertz to purchase 1,003 fastbacks, including two prototypes. Four “experimental” GT350 convertibles were also built for test purposes in anticipation of a 1967-1/2 convertible offering. A small number of the consumer sales 1966 models were factory fitted with Paxton superchargers, but not the No-Spin limited slip differential, for an additional $670, (~$6,292 in 2023) the engine was rated at 440 hp (328 kW).[11][12][13] Total production for 1966 was 2,378 units, including two prototypes and four drag cars, with 1,372 sold to the general public. “1966 Shelby GT350-H
The sales arrangement with Hertz for ~1,000 GT350s to be added to its rental fleet included the proviso that after their rental lives were finished the cars would be returned to Ford, refurbished, and sold to the public as “GT350H” models.[citation needed] Most Hertz cars were black with gold LeMans stripes and rocker panel stripes, although a few were white with blue stripes. The first 85 Hertz cars were available with four-speed manual transmissions and Hertz advertised them as “Rent-a-Racer” cars.[14] During rental, these cars were sometimes used as production class cars at SCCA events, and were rumored to have been returned to Hertz with evidence of roll bars being welded in.[14] Ford pushed another 800 models on Hertz with black paint, gold stripes and black interior, as well as automatic transmissions.” (1.)
When the Hertz cars were returned to Ford to be prepared for sale to the public, high-performance racing parts were often “lost” (presumably at the manufacturer) before final sale”
For 1967 the GT350 still used the K-code HiPo 289 with added Cobra aluminum valve covers. The GT500 was the new model which had the 428 “Ford Cobra” FE Series Cobra Jet v8 with two CFM Holley four-barrel carburetors with a mid-rise aluminum intake manifold.
1967 GT500
The 67 Shelbys were redesigned with a longer hood, different head light configuration and it was heaver. Shelby wanted to try to differentiate the Shelby Mustangs from the Ford Mustangs. Functional rear brake-cooling scoops adorned the rear quarter panels. Ten-spoke, fifteen-inch, cast-aluminum rims were the wheel choice with Goodyear white-lettered radials. The 1967 GT350 came with an iron-block, 289-cubic-inch (4.7-liter) V-8 rated at 306 horsepower and 329 lb-foot of torque. For a pushrod design, the GT350 revved relatively high, with the horsepower peak not in full swing until the 6,000-rpm redline. The car used a single Holley four-barrel carburetor. You had the option of a 4-speed or 3-speed automatic transmission.
In 1968, a new version of the 428 engine known as the Cobra Jet. This new engine featured a unique, 16-bolt exhaust flange. The GT500 was subsequently known as The Cobra GT500 KR. The initials KR stood for “King of the Road.” Ford rated the Cobra jet at 335 hp with 440 lb⋅ft of torque at 3,400 rpm, although the horsepower was considered significantly underreported. The KR engine was left stock adding die-cast aluminum valve covers with “Cobra Lemans” to note Ford’s FE engine family victory over Ferrari at Le Mans in 1966 and 1967.
GT500KR
The GTs lost their Cobra tag for 1969, and again were marketed simply as the Shelby GT350 and Shelby GT500. The GT350 and GT500 for the 1969 model year received an extensive face lift, the body alone increasing in length by 4 inches with some reaching 10 inches. Ford was involved with design and style decisions, with Shelby having little input. The GT350 was now equipped with a 351 cubic-inch V8. Carroll Shelby terminated his agreement with Ford in the summer of 1969. It was designed by John Chun.
No production of 1970 Shelby GT350 and 500 models was undertaken; however, unsold 1969 models were given 1970 vehicle identification numbers under FBI supervision. The 1970 models had two cosmetic changes, a front chin spoiler and two black hood stripes. The rest of the changes had to do with emissions. The GT500 had the carburetor modified and marked “ed” (edited) on tag. The distributor in both the GT 350 and GT500 was changed to a 1970 version.[ A total of 789 were re-VIN’d.[
f