'70s Mustang Dyno Cobra Result Shows the Horrors of the Malaise Era

YouTube channel Late Model Restorations said this is the lowest-powered V-8 it has ever tested. It's not as bad as you think.

Photo by: Ford

By: Chris Perkins

Jul 29, 2025 at 3:00pm ET

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Just how weak was the American performance car in the 1970s? Very weak. New emissions and fuel-economy regulations sucked the life out of the American V-8, and it wasn't until the rise of modern engine management systems that our performance cars got a bit of muscle back. A dyno test of a 1979 Ford Mustang Cobra shows just how grim things got.

YouTube channel Late Model Restoration recently did a mostly cosmetic restoration of this early Fox-body Mustang, and rather than stick a much hotter V-8 under the hood, it kept things stock. On its dyno, the automatic Cobra managed just 125 horsepower and 211 pound-feet of torque at the wheels. That's not terrible since Ford rated this 4.9-liter (badged as a 5.0) engine at 140 hp and 250 lb-ft when new. But also, sheesh. Today's four-cylinder Mustang makes well more than double that.

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That's just 25.5 hp/liter, or 15.6 hp/cylinder. This Cobra's automatic transmission probably isn't doing it any favors, either. And remarkably, this wasn't even the lowest-powered V-8 Mustang: Ford offered a 4.2-liter V-8 in the 1980 Mustang that made just 118 hp.

Things wouldn't be so dark for so long, though. By 1985, Ford managed to get over 200 hp out of its Mustang V-8, and it's been a steady climb ever since. Today's Mustang Dark Horse makes 500 hp out of a V-8 of the same displacement. And if you owned a Mustang Cobra back in 1979, things could've been worse. Late Model Restoration once dynoed a '79 Mustang Ghia, and its naturally aspirated 2.3-liter four-cylinder made just 64 hp.