The Race Against the Mammoth Car (Part 1)

Gangster Cruncher Block enters the humungous Mammoth Car in a race through a mountain area to help smuggle out $50 million in gold.

Plot
When Trixie was granted the position of Speed's assistant in the No Limit World Race, Inspector Detector and his officials search each entry looking for $50 million in stolen gold bars before the race begins. When The Mammoth Car enters the track, its driver gives the Inspector a tour, giving no single trace of the gold. When the race begins, the Mammoth Car forces everyone off the road and even causes a massive train derailment, making Speed a bit suspicious. On its way to discover the Mammoth Car’s secret, he equips the homing robot with X-ray film so he can be able to penetrate the metal.

The robot is shot at and returns home broken. Now, the Mammoth Car catches up to Speed and forces the Mach 5 off the road. When a ramp is lowered, a squad of motorcyclists descends onto the road. Racer X appears and spills oil on the road, causing the bikers to crash. At the airport, Spritle and Chim Chim stow-away aboard on Cruncher Block's airplane. Meanwhile on the road, the Mach 5 and the Mammoth Car both collide and veers off the road towards the forest. While Speed uses his rotary saws to cut down the trees, the Mammoth Car's power mows its own path. Speed turns around and tries to slash the car’s tires, but the Mammoth Car dodges it and encircles the Mach 5. Guns emerge from its sides. Speed closes the cockpit to block the shower of bullets and escapes through a gap and plunges into a lake.

Goofs/Continuity Errors

 * In the English dub, the Mammoth Car's driver brags that the Mammoth Car can go over 500 mph (800 km/h) on any type of road. This is impossible as we see the speedometer of the GRX in a first part of the episode "Fastest Car on Earth" and it supposedly maxed out at 400 km/h (250 mph) and latter the speedometer of the Mach 5 in the second part of the same story which maxed out at 360 km/h (about 224 miles/hour), yet Speed caught up to the Mammoth Car twice.
 * In some shots of the Mammoth Car stopped while the engine is running, its wheels are spinning.
 * The locomotive's wheel configuration constantly changes throughout the derailment scene.
 * In an overhead shot the moment before the train hits the Mammoth Car, the Mammoth Car is shown crossing the tracks again even though in previous shots, the Mammoth Car is still crossing the tracks.
 * When Pops and Sparky arrive at the airport, Sparky's black eye disappears.

Cast

 * Peter Fernandez: Speed Racer, Racer X
 * Corinne Orr: Trixie, Spritle Racer, Mom Racer
 * Jack Grimes: Sparky, Chim Chim
 * Jack Curtis: Pops Racer, Inspector Detector

Dub edits

 * Narration was added in several parts in the English dub that wasn't present in the Japanese version:
 * The opening when Sparky was checking the Mach 5.
 * Spritle and Chim-Chim running to the Mach 5. This replaces dialogue from Spritle that they need to get inside the trunk.
 * When Racer X was looking over at Speed and Trixie before the race starts.
 * When the Mammoth Car crew members were mending the dent from the train collision.
 * When the Mammoth Car was signaling to Cruncher Block.
 * When Racer X was helping out Speed, first during the closeup of him driving and when he spilled oil on the road.
 * The ending when the Mach 5 jumps into the water.
 * Spritle apologizes to his father after he and Chim-Chim jump over him. This was absent in the English dub and just has Pops grunting.
 * After Pops snatches Spritle and lectures him that the Mach 5 is built for 2 people, Sparky remarks that to Trixie and wants to be in the race, continuing the conversation. He doesn't remark this in the English dub.
 * Speed tells both Trixie and Sparky to stop acting up in the Japanese version, whereas in the English dub just only him saying this towards Sparky.
 * The Mammoth Car was blaring its horn when the crowd was running out of the way. This was absent in the English dub.
 * Sparky remarks that the Mammoth Car's length is different in both Japanese and English. It was 40 meters (almost 44 yards) in Japanese and over 200 yards in English.
 * When the Mammoth Car was pulling up, Trixie was asking why the Mammoth Car was entering the race, with Sparky suggesting that it's made for long distances. This was absent in the English dub.
 * The announcer was speaking over when the inspectors are walking towards the cars was only in he English dub.
 * Inspector Detector suggests that Cruncher Block might've been behind the smuggling when the team were inspecting the Mach 5. This was never present in the Japanese version.
 * Inspector Detector's remarks about the Mammoth Car. In Japanese, he asks the crew if they have a chance to win, with them saying they will. In English, he says that having a large car is unfair, with the crew telling them that any car is allowed in the race.
 * When Sparky asks Inspector Detector about the Mammoth Car, his responses are different. In Japanese, he doesn't know much about it and feels a bit annoyed with the mechanic's questions. In English, he just says that the car has almost everything.
 * The stout Mammoth Car driver drags Sparky to an empty room and knocks him out with a wrench. The closeup of the wrench was cut in the English dub. Oddly enough, this was kept in the recut release through "Speed Racer: The Movie" from Streamline Pictures. Though because that part wasn't dubbed, it instead plays a loop of the music from when the driver leaves the room.
 * Spritle suggest that Sparky is gone because he ate too much in the Japanese, whereas in the English, suggests that he might be up to mischief.
 * Pops remarks the Mammoth Car won't win because of its' large body once the race starts absent in the dub.
 * Sparky's remark when he sees Racer X differs in both versions. He is just shocked to see the Masked Racer, whereas in the English dub remarks that he looks familiar. This is likely to connect that Rex and Sparky knew each other before he ran away.
 * The tall Mammoth Car driver spits gum on one of the racers before blowing exhaust fumes to crash them. This was cut in the English dub, though like with Sparky's knockout scene, this was kept in the recut release through "Speed Racer: The Movie" from Streamline Pictures. Though because that part wasn't dubbed, it instead plays a loop of the music from when the Mammoth Car blows its fumes towards the smaller car.
 * Cruncher Block reprimands the Mammoth Car's driver for ignoring the railroad crossing signal in the Japanese dub.
 * Pops' rant at Sparky after finding out what happened to him was trimmed and altered. There was a scene where Pops complains that the Mammoth Car ignored stopping for the train that was cut in the English dub. Also Pops' suggestion to take an airplane was a last minute thing in his mind in the Japanese, whereas in the English dub, he already made plans to get one.