After a series of back-and-forth tests, the rivalry between the S550 Mustang Mach 1 and the new S650 Dark Horse came down to one final, decisive battle on the racetrack. In a recent video, Aussie YouTuber Ross Spec took both cars to Morgan Park Raceway to settle the score once and for all. The day would crown a winner, but it would also end in a dramatic and costly crash.

Both cars hit the track with similar suspension modifications, but there were some differences. The Mach 1 wore its factory Handling Package aero and was fitted with Michelin Pilot Sport 4S tires. The Dark Horse, due to a shipping error, was missing its Handling Package splitter and spoiler and ran on its stock Pirelli P Zero tires. On track, the cars felt completely different.

“The Mach 1 was very pointy on the nose, almost too pointy,” Ross explained, noting it tended to oversteer. “The Dark Horse was the opposite. It tended more to understeer.”

After nine sessions, the lap times told a clear story. The Dark Horse was consistently faster, setting a best lap time of 1:27.5, a full 0.6 seconds quicker than the Mach 1’s best lap of 1:28.1. The data revealed how they achieved their speed differently. The Mach 1 was faster on the long straights, but the Dark Horse carried more speed through the corners. As Ross summarized, “Essentially, the Mach 1 is fast in and the Dark Horse is fast through and quick out.”

A Clear, But Costly Winner

With the official test over, Ross took the Mach 1 out for one final attempt to break into the 1:27.5s. But with cooler track conditions, the car was unsettled. Coming through turn two, he lost control. “And it snapped so fast. She bit me hard,” he recalled.

The car spun and hit a tire barrier, causing some damage. Ross was uninjured but took full responsibility. “I went into the day fully knowing that I wasn’t covered,” he said. “You have to pay to play, and motorsport is dangerous.”

The crash was a brutal end to an epic comparison. The S650 Dark Horse was the definitive winner, proving faster on both the drag strip and the road course. “I can tell you right now that if you bought a Dark Horse over a Mach 1 with the same modifications, you’d be quicker every time,” Ross concluded.

While the Dark Horse may be the new king, he was quick to reassure current owners, stating, “If you already own a Mach 1, I don’t think you have anything to worry about. You still have an amazing car, and it is only slightly slower than the Dark Horse.”