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Cobra Jet! 35th Anniversary
Three and a Half Decades Ago, Ford Unleashed Bob Tasca's Recipe for Factory Big-Block Performance
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For Bob Tasca, enough was enough. As the owner of performance-oriented Tasca Ford in Providence, Rhode Island, Bob was tired of trying to sell 390 Mustangs and Fairlanes as "performance" cars when down the street the competition's showrooms were loaded with SS396 Chevelles and Camaros, Hemi Mopars, and Ram Air GTOs. Even staid old Buick offered a Gran Sport with a 400ci engine rated at 340 hp.
"Do you know how many high-performance (over 300 hp) vehicles were sold in this country in 1966?" Bob Tasca asked Hot Rod in a November '67 article. He answered, "634,434," and followed with a second question: "Do you know how much Ford Motor Company had of this market? Seven and a half percent," he revealed. "That's shameful for a 'Total Performance' company." So Tasca, never one to hold back opinions or delay action, decided to show Ford how to do it.
Tasca Ford was already enhancing customer 390 Mustangs and Fairlanes with '63½ 427 heads, GTA 390 camshafts, adjustable 1.76:1 427 rocker arms, 427 distributors, higher-flow fuel pumps, and more aggressive tuning. For his KR-8 (for King of the Road 1968) package, as it was called, Tasca applied those components to a 428 Police Interceptor block, along with a Police Interceptor aluminum intake with a 652-cfm Holley. Assembled by Tasca's staff, including Performance Manager Dean Gregson and Assistant Parts Manager Glenn Tiberiis, the engine was transplanted into '67 Mustang 390 GTs, which ran low 13-second quarter-miles with street tires and an efficient street exhaust.
Tasca knew he had the solution to Ford's performance dilemma, and as the second largest Ford dealer in the world at the time, he had a direct pipeline to Henry Ford II. "I told him I believed our cars were competitive in price, more than competitive in style and interior appointment, but hopelessly inadequate under the hood," Tasca was reported as saying. "We haven't been the hottest since the flathead V-8, and that was his father's idea, so I couldn't congratulate him for that."
Bob Tasca also pulled off a major coup by getting Hot Rod to run a story about his KR-8, with plenty of references to Ford's lack of performance. To top it off, Tasca convinced Hot Rod to provide an address for Henry Ford II so readers could "vote" in favor of Ford producing a production version of the KR-8. At some point, Tasca's gold '67 Mustang KR-8 prototype ended up in the hands of Ford engineering.
The Tasca ploy worked. By late-1967, the word was out that Ford was putting together a number of 428-powered Mustang fastbacks for Ford drag racers. Hot Rod again got the scoop when they tested one of the cars for the March '68 issue. Then, at the '68 Winternationals, eight of the "rumored" drag cars appeared to compete for the Super Stock championship with name Ford drivers like Dyno Don Nicholson, Gas Ronda, Al Joniec, Jerry Harvey, and Hubert Platt. Joniec defeated Platt in an all-Cobra Jet SS/E final, then went on to claim the overall Super Stock crown by defeating Mopar driver Dave Wren.
On April 15, 1968, Ford made it official with a press release: "The lively image of Ford Division's Mustang and Fairlane takes on added luster with the release of two '68½ high-performance engine packages. Both cars have Ford's recently-announced 428ci Cobra Jet engine as part of a performance package that places them at the top of the supercar category."
It's interesting that Ford elected to rename the engine as opposed to using Tasca's KR nomenclature. Reportedly, Ford had spent a considerable amount of money to retain the rights to the Cobra name and needed to use it in performance applications. Using "Jet" also provided a jab at Chevrolet's Turbo Jet family of engines.
Offered as an option for the Mustang GT, the '681/2 Cobra Jet package added the 335hp 428, utilized in much the same way as Tasca's KR-8 with a 428 short-block, 427 "low-riser"-style heads, unique high-flow intake and exhaust manifolds, and a 735-cfm Holley four-barrel. Also part of the deal was a black hood stripe and a functional hoodscoop for the unique "flapper" air cleaner that allowed cooler outside air to flow into the Holley four-barrel. The '68½ Cobra Jet Mustangs also received an 80-amp/hr battery, competition handling suspension, F70-14 white-letter Goodyear Polyglas tires, power disc brakes, a heavy-duty Top Loader four-speed or C6 automatic, a 9-inch nodular iron rearend, and specially reinforced front shock towers. Four-speed versions also got staggered rear shocks and a tachometer, which was optional on C6 automatic cars.
Shelby also got into the act when the 428 CJ became available. Interestingly, to differentiate the Cobra Jet versions from the earlier base 428-powered GT500s, the CJ Shelbys were called GT500KR, a semi-direct pickup from Tasca's KR-8 nomenclature.
If ever an engine and car were tailor-made for each other, it was the Cobra Jet and the new-for-1969 Mach 1. Based on the freshly-styled SportsRoof, the Mach 1 gushed performance with its hoodscoop, side stripes, and unique interior. When powered by the optional 428 Cobra Jet, the Mach 1 soared into the musclecar stratosphere with cars like the SS396 Camaro, Ram Air GTO, and 440 Road Runners. The Cobra Jet was offered as either the non-ram-air "Q" version or the "R," which added a functional Shaker ram-air scoop.
Sometime during the '69 model year, Ford addressed durability concerns by beefing the Cobra Jet's reciprocating assembly with 427 LeMans-type connecting rods, a modified crankshaft, and an oil cooler. These engines, which became known as Super Cobra Jets, were installed whenever the 3.91 or 4.30 rearend gear ratios were ordered. By February 1969, Ford was marketing the package as the "Drag Pack."
Unlike 1968, when the 428 Cobra Jet was available only with the GT package, the '69 CJ was offered in all Mustang body styles and models, including the GT, which was in its last year, no doubt as a result of the better equipped Mach 1. This availability led to some interesting and rare combinations, like plain coupes, Shaker-scooped convertibles, and California Specials. Even a handful of luxury Grandes were equipped with the CJ engine, although none with ram-air. For Shelby, all '69 GT500s were CJ equipped.
The 428 Cobra Jet rolled over into 1970 basically unchanged, although the Mustang itself received a minor facelift. Once again, the CJ was available in the various body styles and models, including the Mach 1 and Grande, along with standard coupes, convertibles, and fastbacks. For warranty reasons, an electronic rev limiter was added to four-speed CJs in 1970 to prevent the engine from revving over 5,800 rpm.
There is some Ford prototype photography that shows 429 hood striping on a '70 Mach 1 with a Cobra Jet Shaker scoop. That indicates that Ford considered making the change to the 429 Cobra Jet in 1970, which makes sense, because the 428 CJ was replaced by the 429 in '70 Fairlanes and Torinos. With the introduction of the '71 models, the 428 Cobra Jet was finally replaced in the Mustang by the 429 Cobra Jet with its canted-valve heads.
In its 2½-year run as the Mustang's workhorse big-block performance engine, the 428 Cobra Jet redefined Ford's Total Performance image with victories on the dragstrip and muscle on the street. By simply taking existing parts off the shelf and applying them to a passenger-car big-block, Ford created one of the best musclecar engines of all time. Bob Tasca must have been proud.