Blown 427 Clevor Dazzles On The Dyno With Four-Digit Output

Fullboost and HarropTV filmed what might be the meanest positive-displacement V8 they’ve ever seen, and it’s a small-block Ford. Michael Js and Son built a 427-cubic-inch V8 for a Ford Falcon XW, topped it with a race-ported Harrop TVS2650 blower, and strapped it to the dyno. The results were wild.

The engine itself is a work of art, based on a 9.2-deck Dart block with a Callies crank, Oliver rods, Diamond pistons (at 12.5:1 compression), and a set of Higgins Cleveland-style heads. The owner, Michael, originally just wanted a reliable 10-second street car for Drag Challenge. Tony said, “He wanted a 10-second street car that he could drive all the time, do drag challenges with, and be reliable.” That 10-second goal quickly became a distant memory once the Harrop blower started spinning.

On the dyno at Dandy Engines, the 427 revved to an incredible 8,700 rpm. The torque numbers were staggering. Luke from Fullboost recalled it was making 1,000 lb-ft of torque at 8,000 rpm, and off the hit, it was just under 1,200 lb-ft. The session was a masterclass in stepping up the power. The first pull on the lowest boost setting (14 psi) was already impressive.

As they pulleyed down, the power kept climbing: 1,150 horsepower, 1,320 horsepower, and 1,506 horsepower. When they reached the final, smallest pulley, the owner, who was previously happy with 1,300 horsepower, got the ‘red mist.’

Tony recounted the moment: “Michael was like: No, just send it. He goes, ‘I want the other pulley on and send it.’ ” That final pull screamed to over 1,550 horsepower, a new record for the Harrop TVS2650 supercharger that makes use of EATON’s vaunted rotorpack.

Despite the massive power, Tony emphasized that the engine was built with the same care as any 300-horsepower stocker he restores.

Luke was equally impressed that this monster setup was built almost entirely from off-the-shelf components. He concluded, “Credit to you guys because it’s such a good combination. And the reality is, anyone could come here and replicate this.”

This 427-cubic-inch Ford small-block isn’t just a dyno champ; it’s a drivable, serviceable package built to survive the street and dominate the track.