With S650 Mustangs starting to arrive at Ford dealerships across the country, it was only a matter of time before someone stuck one on a dyno. The team at Middleton Ford in Middleton, Wisconsin appears to be the first ones to make it happen, wasting no time getting break-in miles on a fresh 2024 Ford Mustang GT Convertible. Thanks to them, we now have a chance to watch how the updated Coyote compares to its pony car ancestors.

The 2024 model year marks the start of the seventh-generation Ford Mustang, with this particular GT carrying a 5.0-liter V-8 under its hood. The fourth-generation Coyote V-8 gets some updates of its own for S650 duty, including a new dual-intake system, an updated exhaust header, and forged connecting rods. Ford has also fit the V-8 with a new dual-injection setup, as well as a new calibration for 2024. Output is rated at 486 hp and 418 lb-ft of torque, making this the most potent GT model yet.

This particular convertible is equipped with the optional 10-speed automatic, but a six-speed manual is still standard equipment. That automatic makes a dyno test like this a bit trickier, as seventh gear is the 1:1 ratio. In the case of a convertible Mustang such as this, you’ll hit the speed limiter before reaching redline. Middleton Motorsports opted to do these tests in fifth gear, which features a 1.520:1 ratio. That ultimately means the tested figures likely won’t be as high as they actually should be, but it does give us a good baseline idea of how potent the engine is.

The first thing you notice during the run is a somewhat different tone coming from the Coyote. There’s no mistaking the warbly note for anything else, but the tone is different now that those twin intakes are working up front. The first run produced the weakest figures of the bunch, with the car turning out ratings of 397 hp and 352 lb-ft of torque. Things looked a bit better during the second pass, with the crew noting that the engine felt like it had smoothed out a bit. Horsepower was up to 408, but torque dipped slightly at 351 lb-ft. The third run started to trend back down, however, with ratings of 405 hp and 347 lb-ft of torque. The car had less than 1000 miles on it at the time of recording, so it's possible things could improve slightly as the engine and gearbox wear in a bit more.

Despite being unable to wring the car out in seventh gear, the crew still decided to test the output until the speed limiter kicked in. Unsurprisingly, the car produced more power in the correct gear up until the 5600-rpm cut-off. The team believes the car is actually good for around 420 horsepower at the wheels. Luckily, Middleton Ford has a six-speed car gearing up for a dyno run of its own, which has a 1:1 ratio in fourth gear. That should make it a bit easier to get proper figures for the car, even if the automatic will likely be the volume seller in the long run. A Dark Horse model is also in line for some testing, though getting a Mustang GTD might prove a bit trickier.

Now that these cars are hitting the dyno, don’t expect it to take long before we see some crazy figures coming from the S650 chassis.

You Might Also Like

• You Need a Torque Wrench in Your Toolbox

• Tested: Best Car Interior Cleaners

• The Man Who Signs Every Car