Porky's beloved train, the No. 13½ engine named Toots the 15th Century Unlimited, is to be replaced by a streamlined train by the name of Silver Fish. After Dirty Digg, the driver of the Silver Fish insults Toots, Porky mutters that his train could easily take on the streamlined train. Dirty agrees to a race that ends with Porky being the victor thanks to an insulted bull seeking revenge. He becomes the new driver of the Silver Fish whilst a battered Toots is on a trailer behind with "Headin' for the Last Roundhouse" written on a sign attached to it.
On Nickelodeon airings, the original black and white, the redrawn colorized version, and the computer-colorized versions cut the scene where the Silver Fish races by a woodpile and a little black man is revealed, referring to a racially offensive saying. In the redrawn version, the scene with the Silver Fish going through a tunnel and turning it inside out was also gone. In addition, there was sometimes a false "iris-out" so that this cartoon would end with Porky's train flying over the finish line and the crowd cheering; deleted was Porky as the new engineer of the Silver Fish. MeTV also edited this scene in January 2022, but left it intact previously back in June 2021.
- This cartoon entered the Public Domain in 1965.
- During the race, Porky runs over the top of a boat called the SS Leon, a gag dedicated to the cartoon's producer Leon Schlesinger.
- This cartoon reveals that Porky Pig is afraid of bulls.
- Toots is a 2-2-2 engine (two leading wheels, two driving wheels, and two trailing wheels) popularly called a "Jenny Lind", while the 30th Century Limited is a 4-4-2 engine (four leading wheels, four driving wheels, and two trailing wheels), commonly known as an "Atlantic". The wheel alignment of the Silver Fish cannot be discerned.
- When Porky & Toots entered a passing siding to let the 30th Century Limited pass, Porky pulled off a railroad maneuver known as a Saw-By Meet, because Porky's train was too long to fit in the siding.
- When Porky was giving the bull a piece of his mind, Porky was speaking gibberish just before being scared off, what he said was "Toots, Old Gal. Don't pop your..." in reverse.