Pops Racer is refused by the board at his company to pursue the designs for a better, faster engine.  Meanwhile Speed Racer wins an amateur race in the Mach 5 and everyone congratulates him.  He and Pops are on the way home when a gang of motorcycle riders steals the plans from Pops.  Speed is able to get them back with Trixie's help in her helicopter.  Now with Pops on his own he needs money to build his engine.  Speeds talks with Sparky about it and leans that there is a race where the winner can get $5,000.  Speed enters the race and unknowingly installs the windshield that Pops has drawn the engine designs on into the Mach 5.  During the race, a gang of black car drivers go after the Mach 5 in order to get the plans.  Speed uses his car jacks to escape but heads down a sheer cliff in the process.