For 1989, the 20th-anniversary turbo Trans Am project (originally conceived by Bill Owen of Pontiac) was outsourced to PAS, Inc., an engineering firm led by Jeff Beitzel. Beitzel and his team did most of the TTA development work. The 3.8 L turbocharged V6 engines were built by PAS at their 40,000 square foot City of Industry, CA plant. From there, they went to GM's plant in Van Nuys, CA to be installed into GTAs on the F-Body assembly line. The cars were then shipped back to PAS for final assembly, testing, and quality control. Incidentally, the GTA chassis were selected at random, thus there is no correlation between the VIN and production sequence number. The initial number of cars to be produced had ranged from 500 to 2,500 until GM finally settled on 1,500. In all, a total of 1,555 Turbo Trans Ams were manufactured. One of these served as the 1989 Indianapolis 500 pace car.