Donald Farr
Former Editor, Mustang Monthly
October 1, 2003
Photos By: Mustang Monthly Archives

The explosion took place from 1964 to 1971, right in the Mustang's prime time. Although 427 Galaxies and Hemi Chryslers had previously roamed the streets, it was Pontiac that took the initiative to drop a performance big-block into an intermediate-sized car. The resulting GTO, with a 389, four-speed, and available Tri-power, launched a youthful revolution for fast cars. The Mustang, with sporty lines and seats for at least four, and often five, provided an ideal platform for performance cruising on the Woodward Avenues of America. For eight years, the Mustang ran fender to fender with the best of the American musclecars. Starting with the 289 High Performance option in 1964, the Mustang quickly evolved into Shelbys, Cobra Jets, Bosses, and Mach 1s. Bench-racing lore, no doubt fueled by hot rodders at the dragstrips popping up in nearly every town, created legends about 12-second--even 11-second--Mustangs straight from the dealership.

But how fast were they really? Our most reliable source of information comes from the road tests of the day. Granted, some of the cars were, shall we say, tweaked from Ford, and others fell into the hands of inexperienced magazine road testers. Still, the road-test times, along with the information in the articles, provide our best glimpse into the past.

For our research, we scoured our back-issue library and relied heavily on How Fast Were They? This book, from GaS Publishing (3 Meadowood Dr., Washington, MO 63090), is a compilation of road-test times and data from 1948 to 1973. Thanks also to our senior editor, Jim Smart, who searched the vast Primedia (formerly Petersen Publishing) photo archives for many of the accompanying photos, some of which are seen here for the first time.

'65-'66 289 Hi-Po

Obviously, the Mustang's introduction in 1964 generated a lot of coverage in automotive enthusiast magazines. Most reported on the basic Mustang--after all, it was a fresh design in a new era of baby-boomer car buying. However, several magazine staffs managed to get their hands on the top performance model with the 271hp 289 High Performance engine, all with four-speeds.

We're still trying to figure out how Car & Driver squeezed a 14-flat at 100 mph out of a '65 Hi-Po fastback in its October '64 comparison to the Plymouth Barracuda. The only explanation offered was, "We got acceleration figures almost in the Cobra class with the 4.11 ratio. . . . " Yet, that doesn't fully explain why the Car & Driver fastback was nearly 2 seconds quicker than other 289 Hi-Po road tests.

The high 15-second times from Motor Trend and Sports Car Graphic are more in line with the actual performance potential of the factory-stock 289 Hi-Po Mustangs. Judging from the photos and the same "014" manufacturer's license plate, the hardtop tested by Motor Trend and Sports Car Graphic for late-'64 issues was likely the same press car. Indeed, based on the identical 15.7/89-mph time and the fact that both magazines were published by Petersen Publishing, we can assume the magazines shared the same test results. Strangely, Motor Trend said the car was equipped with 3.89 gears, while Sports Car Graphic reported 4.11s.

'65 Fastback - 14.0/100 - 4-spd. - 4.11 - Car & Driver, Oct. 1964
'65 Hardtop - 15.7/89 - 4-spd. 4.11 - Sports Car Graphic, Sept. 1964
'65 Hardtop - 15.7/89 - 4-spd. 3.89 - Motor Trend, Aug. 1964
'65 Fastback - 15.9/89 - 4-spd. 3.89 - Motor Trend, Jan. 1965

'65-'66 Shelby GT350

When the Shelby GT350 hit the scene in 1965, the enthusiast press jumped all over it. Powered by a 306hp Cobra version of the 289 High Performance and equipped with suspension modifications for improved handling, the GT350 was more race car than road car, especially in 1965, when it had side exhaust and no rear seat.

By 1966, the GT350 was a bit more refined, but it was also available with an optional Paxton supercharger, a package that boosted the Shelby's performance to 14-flat, as evidenced by the test reports in both Motor Trend and Car Life in the summer of 1966.

Most naturally aspirated GT350s performed in the high-14, low-15-second range, including a Hertz rental car version with the automatic transmission. Oddly, the '65 tested by Motor Trend was a full second slower than the one tested by Car Life.

'66 GT350S - 14.0/102 - auto - 3.89 - Motor Trend, Aug. 1966
'66 GT350S - 14.0/92 - auto - 3.89 - Car Life, July 1966
'65 GT350 - 14.7/90 - 4-spd. - 3.89 - Car Life, June 1965
'65 GT350 - 14.9/95 - 4-spd. - 3.89 - Car & Driver, May 1965
'66 GT350H - 15.2/93 - auto - 3.89 - Car & Driver, May 1966
'66 GT350 - 15.6/94 - 4-spd. - 3.89 - Motor Trend, Aug. 1966
'65 GT350 - 15.7/91 - 4-spd. - 3.89 - Motor Trend, May 1965

'67-'68 390

Car Life called it the "Super Double Deluxeburger Mustang" because Ford decided to add the 390 big-block to the Mustang's engine lineup. With 320 hp and 427 lb-ft of torque, the pony-sized Mustang finally had some beef to compete against big-block GTOs and Barracudas, not to mention the new 396 Camaro. In stock form, the 390 Mustang was a low-to-mid-15-second performer, as evidenced by most of the road tests. Car & Driver reported a 14.8-second e.t. and even complained that the car was not in optimum tune, but failed to provide the transmission type or how they managed to obtain a quicker time than anyone else. Hi-Performance Cars magazine, however, explained that it took a set of slicks and traction bars to register their 14.95-second e.t., stating, "Normally, the 390 engine cannot be considered hot by today's standards. However, when packed into a light Mustang, you have a pretty impressive machine."

'68 GT Fastback - 14.8/94.6 - N/A - 3.25 - Car & Driver, March 1968
'67 GTA Fastback* - 14.95/97.60 - auto - 3.25 - Cars, Sept. 1967
'68 Fastback - 15.2/94 - auto - 3.25 - Motor Trend, Jan. 1968
'67 GTA Fastback - 15.2/91 - auto - 3.00 - Car & Driver, Nov. 1966
'67 GTA Fastback - 15.31/93.45 - auto - 3.25 - Hot Rod, March 1967
'67 Fastback - 15.5/91.4 - auto - 3.25 - Car Life, Jan. 1967
'67 N/A - 15.6/94 - 4-spd. - N/A - Motor Trend, May 1967

*Slicks and traction bars

'67 Shelby

We grouped the '67 Shelby GT350 and GT500 together because they are truly one-of-a-kinds. The 306hp version of the 289 High Performance still powered the GT350, but the restyled '67 was heavier than its '65-'66 counterparts, and in 1968, Shelby went with the 302 4V. For the new GT500, Shelby utilized a 355hp 428 with twin Holley four-barrels, a setup that disappeared for 1968.

Sports Car Graphic, with Shelby-American team driver and Sports Car Graphic Editor Jerry Titus handling the testing and writing duties, squeezed the best times out of the GT350 and GT500, 15.3 and 14.3 respectively. Car & Driver was disappointed with its 15-flat e.t., but noted, "What the old Shelby Mustang (earlier GT350) does with difficulty, the GT500 does easily."

Motor Trend pitted the GT350 and GT500 against small-block and big-block Corvettes. Even though the GT350 posted only a 15.9, it beat out the small-block Corvette's 16.1 e.t. However, the GT500, with a 14.5 time, stood little chance against a 435hp Tri-power Corvette, which ran a 13.8.

'67 GT500 - 14.3/92 - auto - 3.25 - Sports Car Graphic, March 1967
'67 GT500 - 14.5/101 - 4-spd. - 3.89 - Motor Trend, May 1967
'67 GT500 - 15.0/95 - auto - 3.25 - Car & Driver, Feb. 1967
'67 GT350 - 15.3/91 - 4-spd. - 3.89 - Sports Car Graphic, March 1967
'67 GT350 - 15.50/92.90 - 4-spd. - 3.89 - Popular Hot Rodding, Feb. 1967
'67 GT350 - 15.9/90 - 4-spd. - 3.89 - Motor Trend, May 1967

'68 Shelby

Apparently, there wasn't much to talk about when the '68 Shelbys debuted. With a 250hp, 302 four-barrel replacing the 306hp, solid-lifter 289 Cobra in the GT350, and a single-four 428 taking the place of the previous year's dual-quad big-block, the magazines of the day basically ignored the '68 Shelbys.

Regardless, the GT500 turned in respectable mid-14-second e.t.'s, while the GT350 posted high 14s, which were, surprisingly, quicker than the tests of the '67 GT350s. At mid-year, however, the GT500 became the GT500KR with the 428 Cobra Jet engine, which is listed below with all the CJ Mustangs.

'68 GT500 - 14.56/99.77 - auto - 3.50 - Super Stock, Aug. 1968
'68 GT500 - 14.75/98 - auto - 3.50 - Motor Trend, March 1968
'68 GT350 - 14.9/96 - 4-spd. - N/A - Hi-Performance Cars, Sept. 1968
'68 GT350 - 14.9/94 - 4-spd. - N/A - Road & Track, June 1968

'68 ½-'70 428 CJ

In the first-ever test of a factory 428 Cobra Jet Mustang, Hot Rod magazine called it "the fastest running pure stock in the history of man." Granted, the test fastback, which ran a 13.56 at 106.6 mph, was a prototype of the 50 cars that would be provided to Super Stock racers, but the hype from a respected magazine like Hot Rod was the perfect introduction to the engine designed to save Ford's performance reputation.

For nearly three years, magazine staffers pounded on Cobra Jet Mustangs. The GT500KR received most of the '68 glory, as the magazines clamored after the Shelby instead of the GT Mustang version. Hot Rod managed a 14.01 from a four-speed, 3.50-geared KR fastback, while in the same test, a heavier convertible with automatic and 3.25s ran a 14.58.

When the Cobra Jet-powered '69-'70 Mach 1s with the new Shaker hoodscoop arrived in 1969, right in the middle of the frenzied musclecar action, the automotive press praised the car with comments like, "A blend of dragster and Trans Am sedan," "Best Mustang yet," and "The new success car." With the Mach 1, the 428 Cobra Jet big-block finally had a total performance package.

The numbers backed up the image. The '69-'70 CJ Mach 1 tests all fell within the high-13-, low-14-second range. Surprisingly, the 13-second timeslips came from automatics, while the four-speed cars were in the low-14s.

'68 ½ Fastback - 13.56/106.6 - 4-spd. - 3.89 - Hot Rod, March 1968
'69 Mach 1 - 13.86/102 - auto - 3.91 - Car Life, March 1969
'69 Mach 1 - 13.89/101.50 - auto - 3.91 - Car Craft, March 1969
'69 Mach 1 - 13.94/103 - auto - 3.91 - Super Stock, Feb. 1969
'68 ½ GT500KR - 14.01/102/73 - 4-spd. - 3.50 - Hot Rod, Nov. 1968
'70 Mach 1 - 14.03/98.89 - 4-spd. - 3.91 - Popular Hot Rodding, March 1970
'69 GT500 - 14.07/103.56 - 4-spd. - 3.91 - Super Stock, Sept. 1969
'70 Mach 1 - 14.11/101.12 - 4-spd. - 3.91 - Super Stock, Nov. 1969
'69 Mach 1 - 14.3/100 - auto - 3.91 - Car & Driver, Nov. 1968
'70 Mach 1 - 14.31/100.22 - 4-spd. - 3.91 - Road Test, Feb. 1970
68 ½ GT500KR - 14.57/99.55 - 4-spd. - 3.50 - Car Life, Oct. 1968
'68 ½ GT500KR Convertible - 14.58/97.71 - auto - 3.25 - Hot Rod, Nov. 1968

'69-'70 Boss 302

Like the 428 Cobra Jet, the Boss 302 arrived just in time. Designed to compete with Chevrolet's Z/28 Camaro both on and off the track, the Boss 302 revived Ford's small-block performance image after nearly a year-and-a-half lapse since the 289 High Performance went away after 1967.

According to the drag tests of the day, the '69-'70 Boss 302 Mustang was a steady high-14-second performer. Super Stock magazine, which was known for tweaking its test cars to get the best times possible, managed a 14.03 with experienced drag racers behind the wheel of a 4.30-geared '70 model. With slicks and the Shaker air-cleaner assembly removed, the Super Stock crew dropped the e.t. to 13.43 at 102.70 mph.

'70 Boss 302 - 14.03/100.55 - 4-spd. - 4.30 - Super Stock, Jan. 1970
'69 Boss 302 - 14.57/97.57 - 4-spd. - 3.50 - Car & Driver, June 1969
'70 Boss 302 - 14.62/97.50 - 4-spd. - 3.91 - Hot Rod, Jan. 1970
'69 Boss 302 - 14.75/98 - 4-spd. - 3.50 - Super Stock, Sept. 1969
'69 Boss 302 - 14.85/96.15 - 4-spd. - 3.91 - Car Life, Sept. 1969
'70 Boss 302 - 14.93/93.45 - 4-spd. - 3.91 - Car & Driver, Feb. 1970
'70 Boss 302 - 14.98/96.87 - 4-spd. - 3.91 - Car Life, June 1970
'69 Boss 302 - 15.0/96 - 4-spd. - 3.50 - Sports Car Graphic, June 1969
'70 Boss 302 - 15.8/90 - 4-spd. - 3.50 - Motor Trend, April 1970

'69-'70 Boss 429

With all the praise heaped on the Mach 1 and Boss 302, the Boss 429 Mustang must have raised the expectations of the magazine road testers. Even though Super Stock and Hi-Performance Cars posted solid 13-second times for the '69 Boss 429 (apparently with the same car obtained from a Ford dealership), they were less than flattering with their headlines of "Ford's Not-So-Boss 429" and "Boss Loss." It almost sounds as if they were expecting a 12-second factory musclecar right out of the box, and they were disappointed when the big hemi-headed 429 mustered only 13s. However, Car Life came away impressed, even with a 14.09 e.t., as they tagged the Boss 429 as the "best enthusiast car Ford has ever built."

'69 Boss 429 - 13.34/112 - 4-spd. - 3.91 - Cars, Sept. 1969
'69 Boss 429 - 13.64/104.65 - 4-spd. - 3.91 - Super Stock, June 1969
'69 Boss 429 - 14.09/102.85 - 4-spd. - 3.91 - Car Life, July 1969

'71 429 CJ

Apparently, the debut of the 429 Cobra Jet in the '71 Mustang was overshadowed by the new-for-'71 Boss 351. Thanks to GaS Publishing's How Fast Were They? we know that at least three major magazines tested the 429 CJ Mach 1.

Unfortunately, none of the magazines could be found in our magazine library, so we were unable to verify the times and information about the cars.

'71 Mach 1 CJ - 13.40/105 - auto - N/A - Sport Car, 1971
'71 Mach 1 SCJ - 13.97/100.22 - auto - N/A - Super Stock, Feb. 1971
'71 Mach 1 SCJ - 14.61/96.8 - auto - N/A - Motor Trend, Jan. 1971

'71 Boss 351

The amazing thing about the '71 Boss 351 road tests is the middle-block-powered fastback ran as quick as the earlier 428 Cobra Jet Mustangs. Of course, with news already out about the upcoming compression drop for all cars in 1972, the Boss 351's impressive performance was overshadowed by doom and gloom.

It appears the three magazines from Petersen Publishing--Hot Rod, Car Craft, and Sports Car Graphic--were supplied with the same Boss 351 press demonstrator, because the car had been equipped with headers, traction devices, and other tweaks by Bill Stroppe. Sports Car Graphic, which admitted, "We don't push our cars to the precipice for record e.t.'s," reported a 14.7 e.t., while Car Craft thrashed the car to a 13.74. Although we couldn't locate a published Hot Rod test of the Boss 351, Sports Car Graphic reported that its sister magazine "maybe even speed-shifted" the same Boss to a 13.9 quarter-mile.

'71 Boss 351* - 13.74/104.28 - 4-spd. - 3.91 - Car Craft, March 1971
'71 Boss 351 - 13.80/104 - 4-spd - 3.91 - Hot Car, May 1971
'71 Boss 351* - 13.9/104 - 4-spd. - 3.91 - Hot Rod, N/A
'71 Boss 351 - 13.93/100.55 - 4-spd. - 3.91 - Super Stock, March 1971
'71 Boss 351* - 14.7/96.2 - 4-spd. - 3.91 - Sports Car Graphic, March 1971

*Headers