Back in the early '60s, the horsepower war began in Detroit, and by 1967, it had become a very serious business. No longer was the Mustang alone in the ponycar class. It was joined by a potent nemesis in the form of the Chevrolet Camaro, which could be had with a rip-snortin' 396-cubic-inch engine making up to 375 hp. This engine featured a special canted-valve cylinder head that had in fact been developed for the Mark IV "mystery motor" for the '64 Daytona 500. In short, the 396 Chevy ran hard.
Here was new competition that did not exist for the Ford Mustang in '65-'66. Ford then offered the FE-series 390-cubic-inch engine for the '67 Mustang, which featured among other things an enlarged engine bay. Although the 390 engine helped Mustang performance considerably, it still lagged behind the potent Chevrolet big-block. Something had to be done. That something became known as the 428 Cobra Jet. First offered in the Mustang April 1, 1968, the Cobra Jet enabled Ford to compete against Chevy in the showroom horsepower wars and to battle it effectively on the racetrack. Perhaps we should say very effectively: Hot Rod magazine's March '68 road-test results show 0-60 times of less than six seconds. Quarter-mile times in the high 13s at about 100 mph were possible right out of the box.
With this short background in mind, it's easy to appreciate the significance of Rob Petrie's beautiful '68-1/2 428 Cobra Jet Mustang convertible. This is no ordinary car. Not only is Rob's car a spotless Cobra Jet, it's a ragtop, and it's equipped with the GT package. The car has the heavy-duty C6 trans, with power routed to a stock 9-inch rearend equipped with a 3.50:1 ratio. The car is an historic vehicle and one of the relatively few Cobra Jet GT convertibles.
This car makes our knees wobble when we inspect the flawless Candyapple Red finish in contrast with the snow-white fabric top. Factory-correct GT styled-steel wheels shod with fresh Goodyear reproductions for the original tire size of F-70x14 enhance the showroom-floor look of this car. We love this look, and we can't decide whether we'd like to take our pal to the drive-in or clean the clock on some unsuspecting Camaro. Even if you look closely, you won't see any outward indication of the car's status as a Cobra Jet. You won't find any emblems, there are no side pipes--not even any numbers on the hood. This factory sleeper lulls the competition with its pretty-as-you-please appearance, then delivers tire-smokin' performance at the go light.
Underhood also sets our knees a-wobbling with show-winning attention to detail. And we do mean show-winning. This car has won Best of Show, First Place, Highest Scoring, and more at many western United States car shows. It's wall-to-wall beautiful 428 FE in here, with everything factory-perfect right down to the air cleaner with vacuum-actuated flapper valve and correct underhood grease-pencil markings. The correct battery, FoMoCo hoses, and required smog equipment round out the picture here.
If you're wondering about the specs for this awesome mill, here are a few to contemplate. The bore and stroke are 4.130 by 3.984 inches for a true displacement of 428 cubic inches. The compression ratio is 10.6:1, with carburetion handled by a Holley 735-cfm four-barrel carb. All of this combined in 1968 to yield 335 factory-rated hp. Published with insurance rates in mind, the factory estimates were intentionally low. The true horsepower figures are much closer to 400 than 300.
This car represents a close second to the ideal Mustang. Here we find the best of both worlds in that this is an exceptional car that has the stock look as well as a perfect color and option combination. It would be hard to top this superior combination. The GT package, convertible top, and 428 Cobra Jet engine would seem impossible to beat. With this engine, there's no need to wind it to the sky, because for the competition, it'd be all over by five-grand anyway. Perhaps one could argue that a four-speed Top-Loader transmission would be better, but we don't agree. As a matter of fact, we'd just leave it in "D."