Power.

Watch Dreadnought and Strega, a heavily modified Hawker Sea Fury and a P-51 Mustang, do their thing in this video.

When Strega's pilot gives it the throttle on the takeoff roll, look how light the plane suddenly gets on the mains. Horsepower numbers are fairly closely guarded in the racing world, but Strega's built-to-the-hilt racing motor is probably churning out more than 3,800 hp, well over double what a stock Rolls Royce Merlin puts out.

Meanwhile, watch when Dreadnought's tail wheel comes up off the ground and the tail kicks to the right a little, despite the noticeable amount of rudder the pilot's got dialed in to keep it going straight.

Instead of its original 18-cylinder twin-row Bristol Centaurus radial, Dreadnought has a 71+ liter four-row Pratt & Whitney R-4360 Wasp Major. Boasting more cubic inches than a grave, the R-4360 in Dreadnought bears about as much resemblance to its original form as a transport plane & bomber engine as the motor in Dale Jr's car does to the lump in a taxicab. The Centaurus had ~2,500hp, and a stock R-4360 had more like 3,500; Dreadnought's powerplant is presumed to put out comfortably more than 4,000.

That sound, though... I'll be in my bunk.
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