The 1978 and 1979 Dodge Magnum in the United States and Canada was an addition to the Chrysler line up that allowed Richard Petty to continue racing with a Mopar. The Magnum replaced the Charger SE in Dodge's lineup in two forms; the "XE" and the "GT". It was the last vehicle to use the long running Chrysler B platform. The appearance was somewhat of a rounded off Charger, and was in response to getting a car that would be eligible for NASCAR that would be more aerodynamic, something the 1975-78 Charger was not. Styling features included four rectangular headlights behind retractable clear covers, with narrow opera windows, and an optional T-bar or power sunroof. The Magnum was well-featured with power steering, brakes and seats; the suspension included Chrysler's standard adjustable, longitudinal torsion bars, lower trailing links, and front and rear anti-sway bars. The base engine was the 318 in³ V8 with Lean Burn, while two and four-barrel carbureted 360 and 400 V8s were also available; weight was nearly 3,900lb (1,800kg). The 400 was dropped from the option list in 1979 as Chrysler stopped production of big-block V-8's in production cars at the end of 1978. A performance model, the "GT" was available with the "E58" police interceptor engine, HD suspension, special axle, special "GT" badging and a "turned metal" dash applique. Technology was advanced for the time with an onboard spark control computer from inception, electronic ignition, and a lockup torque converter. The Magnum name was discarded quickly in favor of the Mirada, a smaller car that was also a rebadged Chrysler Cordoba. The Magnum has something of a cult following today, with several clubs and enthusiasts who are dedicated to the recognition and preservation of Chrysler's "last B-body". In 1979, they made 3,704 Dodge Magnums with the T-Top.
For the 1978 NASCAR season, the 1974 Charger that Chrysler teams had continued to use was no longer legal. While the aerodynamic shape of the Magnum was certainly not a problem, the lack of factory support was. This, combined with the lack of development of the small-block Chrysler V8 as a race engine left the car at a disadvantage. Richard Petty was particularly harsh in his criticism of the car. By the latter half of the 1978 season, Petty and Neil Bonnett switched to Chevrolets, leaving independent drivers Buddy Arrington and Frank Warren to soldier on without factory support. From August 1978, 2-5 independent teams showed up with Magnums in NASCAR races until January 1981, when NASCAR switched to smaller bodied cars. The Magnum never enjoyed the racing heritage of its predecessors, but it was not without its own glorious moments. Petty scored 7 top five finishes in his 17 races with the car, and Neil Bonnett won three poles and scored 5 top five finishes with his. Richard Petty recognized the Magnum with a commemorative decal, depicting his famous number 43 emblazoned on a Magnum for his 1992 Fan Appreciation Tour. Though he never won a race in a Magnum, Richard Petty's son, Kyle Petty drove one of his father's old Dodge Magnums in his first super-speedway race (1979 Daytona ARCA 200), and won! As of now (JUL 2008) only two NASCAR Magnums still exist; one (an ex-Petty car) resides in the Talledega NASCAR museum, and the other; (Marty Robbin's 1978 Magnum #42) has been superbly restored and is owned by a private party in southern CA. The owner plans on racing it in the vintage NASCAR series.