'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