History
The Chevrolet Division of General Motors (GM) saw the need for a mid-size model to add to their lineup; something between the Chevy II/Nova line and the full size Chevrolet. Their design and engineering departments set out to create such a car and on September 26, 1963 the Chevelle family was introduced to the public. The Chevelle’s main competitor outside of General Motors was Ford’s mid-size Fairlane. From inside the GM family, Buick redesigned the Buick Special from its previous unibody construction to the A-body form of body on frame. Oldsmobile followed suit with their F-85 and Pontiac joined in with their Tempest. Cadillac was GM’s luxury line and never felt the need to enter into the mid-size market.
The Chevelle would have multiple body styles, series names, creature comforts, and options over the years just as its internal General Motor rivals Buick, Oldsmobile, and Pontiac. With baby boomers coming of age and looking for inexpensive transportation that had style and performance, GM’s lineup offered a myriad of choices for the buyer. Since Chevrolet was the ‘bread-and-butter’ of GM and offered a lower entry cost for the young consumer, Chevrolet’s Chevelle has something for everyone from entry level 300/300 Deluxe series with minimal trim and creature comforts to the Malibu and SS396 series with upgraded trim and interiors, station wagons for the young family, convertibles for the drop-top enthusiast, and the sedan pickup (El Camino) half-truck, half-car was resurrected into the Chevelle family; truly something for everyone.
GM’s Pontiac Division broke the performance barrier with the GTO option on their 1964 Tempest. John DeLorean, Bill Collins, and Russ Gee were responsible for the GTO in 1964. Although GM’s management banned divisions from involvement in racing, Pontiac disregarded GM policy of limiting the mid-size A-body platform to a maximum of 330 cubic inches for their engines. Pete Estes was president of the Pontiac Division from 1961 to 1965 and approved the Pontiac 389 CID engine with the GTO option. With their 3x2 carburetor setup the GTO pumped out an amazing 348hp with the GTO option. Buick and Oldsmobile had nothing to compete with Pontiac and Chevrolet’s best initial offering was their tried and true 283 CID engine with 220hp. Chevrolet did respond in March with a 250hp version of the 327 CID engine and again in June with a 300hp version. Still far short of the 348hp, 389 CID monster the GTO option offered.
Pete Estes moved to the president of Chevrolet Division in 1965 and started the ball rolling for the largest division of GM and remained in this position until he was promoted to executive vice president of GM in 1972. During these years the Chevrolet Division saw the beginning (and end) of Chevrolet’s participation in the horse power wars of the 60s and 70s.
Through the 60s and into the 70s this cubic inch/horsepower ‘war’ would rage within General Motors, as well as Ford Motor Company, Chrysler Corporation, and to some extent, American Motors, until the peak was reached with the 1970 Malibu with the SS454 option and their 454 CID, 450hp LS6 monster. This December 1969 introduction to the Chevelle would become the highest advertised horsepower rated engine in any production car on the market for the 1970 model year and would be surpassed by any other muscle car of the era. A total of 4,475 Regular Production Option (RPO) LS6 engine options were sold in 3 Chevelle Malibu body styles; the sport coupe, the convertible, and the Custom El Camino. Transmission choices were limited to the heavy duty Muncie RPO M22 4-speed or the heavy duty RPO M40 Turbo-Hydramatic 400 (TH400) 3-speed automatic.
The Tonawanda Engine Plant production figures do show that 3,525 LS6 engines were built for a manual transmission (obviously the M22) and 1,923 were built for the automatic (heavy duty TH400) for a total of 5,448 LS6 engines. Of those, 4,475 went into production Malibus and 973 were service engines. One can take those figures and ‘guess’ or calculate a statistical number how many production LS6 Malibus were equipped with either transmission but, it is still a guess since the M40 transmission, as an RPO number, was available with the newly introduced LS3 402 CID 330hp engine along with the LS5 and LS6.
The same can be said for specific engines vs. body styles. The number of LS6 engines sold is not broken down by the particular body style they were sold in. One can extrapolate a statistical distribution of sport coupes, convertibles, and El Caminos that got the LS6 engine but, like the engine/transmission combination, it is only a calculated, distributive number. Then throw in things like the RPO ZL2 cowl induction hood (which could also be ordered with the two 396 engine options) and you can see how claims of “1-of-xxx” LS6 4-speed convertibles with the ZL2 hood option can get a bit silly
The 60s and 70s were days of “race on Sunday and sell on Monday.” Chevrolet’s Chevelle was never really that competitive in oval track racing such as NASCAR like Ford and Chrysler but straight-line performance at drag racing, that’s another story. Two of the more famous 1970 Malibus on the drag racing circuit were undoubtedly the Ray Allen piloted The Briggs Chevrolet LS6 Fathom Blue convertible, tuned by performance specialists Truppi and Kling, that pretty much dominated the SS/EA class in NHRA by never losing a class race except those occasions when he might red light himself out of competition, and Bob Hamilton’s LS6 Cranberry Red “Red Alert” sport coupe in SS/DA class. AMT model car kit company introduced a 1:25 scale model of Red Alert (albeit a 1972 Malibu model) and became a primary sponsor on the car for a number of years. Although NHRA required at least 50 cars be built for a particular class, it has been claimed NHRA relaxed the rules a bit to allow the Ray Allen car to compete; so whether there were actually at least 50 LS6 convertibles built will continue to be a question as GMs production records were destroyed years ago.
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1970 Chevelle SS396/SS454 Build Sheet Decode Program 1964-1972 Ship Manuals & Parts Catalog 1953-1972 Chevrolet Production Numbers |
