No one in their right mind would call the all-new 2020 Ford Shelby GT500 Mustang a slow car. With a manufacturer-claimed 760 horsepower at the flywheel, the supercharged super-'Stang is about the furthest thing from it, far exceeding the Dodge Challenger SRT Hellcat in terms of peak output and nearly matching the sensational Hellcat Redeye.

That said, there's always room to grow, and Mustang tuner Ken Bjonnes of Palm Beach Dyno set out last month to show what a few software tweaks can accomplish. Working with customer Lee Dennis's 2020 Shelby GT500 on the dynamometer, Ken reprogrammed the engine control unit to make full use of 93-octane gasoline and bumped the redline by 500 rpm.

The results are pretty dramatic.

From the factory, Lee's GT500 was putting out about 664 horsepower at the rear wheels, representing about a 13-percent loss through the drivetrain, assuming Ford's 760-horsepower rating is accurate. Ken first tried Palm Beach Dyno's K2 Ultraflow air filter with the GT500's stock tune, to see whether it was measurably better than the Shelby's original filter, but it didn't yield any advantage.

So, Ken applied Palm Beach Dyno's 93-octane tune, realizing gains of about 39 horsepower at the wheels, with about a 19-lb-ft bump in peak torque. But power with both the stock tune and with Palm Beach Dyno's 93-octane tune was still climbing as the GT500 hit its 7,500-rpm redline, so Ken raised the rev-limiter to realize even more gains.

By the end of the session, Lee's 2020 Ford Shelby GT500 Mustang was peaking at around 720 wheel horsepower, with a gratifying 8,000-rpm redline. If we assume the same 13-percent drivetrain loss as before, that would put Lee's Shelby at more than 810 horsepower at the crank - a monumental figure on par with the Dodge Challenger SRT Demon's 808-horsepower rating on pump gas.

Now just imagine what kind of gains might be achievable with some additional mods.