The GT SeriesEdit
Produced in 1969, the GT series of the FS260 was specifically made for road racing purposes. It came available with a Turk 5-speed manual transmission and a 330 horsepower V8 engine capable of pushing the FS260 GT to 175 MPH, the fastest FS260 of the time. Only 200 GT series FS260's were produced and most have been preserved in the Fortner Museum of Racing building of their Missoula headquarters including a Penske-built FS260 GT that won the 1971 Production B Series Championship in the National Grand American Racing Tour (NGART) driven by Marvin Fortner.
The GS SeriesEdit
Made in the early 70's, the GS series was a step above the GT bretheren. Short for "Grand Sport", it was made for success in the IMSA Delta Cup Series, the largest stock car racing series in the nation. An inspiration of the Pontiac GTO and Buick Grand National GNX, the FS260 GS made 360 horsepower, pumped 427 cubic inches and made a top speed run of 195 MPH unrestricted, and 176 MPH restricted. The GS was a major test bed for restrictor plate racing on larger 2.5 mile ovals where speed has been a factor in major accidents of the past. It was not applied until 1984 when the GS90 made its debut on the circuit. 550 GS series FS260's were produced. 318 have been auctioned, preserved in museums, or have been remodified for historic racing. 83 were destroyed, but most have been restored. The most prominent of the GS series is the #88 car driven by Marvin Fortner, who had come off his 1971 NGART Production B Series championship in the GT series FS260. The #88 car claimed the 1975, 1977 and 1979 Constructor's Championships.
The ZR SeriesEdit
It is regarded as the most prestigious high performance FS260 to date. ZR stands for "Zora-Ruchmiedt", which is Johan Zora-Ruchmiedt, a revolutionist in high performance racing vehicles. He was the pioneer in the GT and GS series of FS260's throughout the 60's and 70's. But it was time to put high performance to a newer level and the ZR is the very trim level for which it pushed the limits. The inspiration of the ZR came from Fortner's sister company, Tempra, maufacturer of the Tantrum, a hybrid of half Ford Mustang Mach 1, half Plymouth Road Runner. The Tantrum was produced in Germany by Ruchmiedt-Tempra AG. Fortner and Tempra's lead designer put the works of the Tantrum into the ZR series of the FS260. The first generation ZR produced 400 horsepower matted to a 445 cubic inch block, the most powerful FS260 engine block of its kind. It pushed the ZR to nearly 200 MPH in high speed testing. Since 1985, nearly 1 million ZR series FS260's have been produced. In 2013, it celebrated its 1 millionth delivery with a special badge applied to the car that reads "1 Million FS260 ZR's".