Originally Posted by
UAL T38 Phlyer
That was the source of the Griffon used in the "Red Barnon 51," (RB-51); a highly modified P-51 that set a speed record for piston-powered airplanes (499 mph, if memory serves).
I saw a late-model P-47 (too late for WWII) in the "Planes of Fame" museum. The placard claimed it just barely exceeded 500 mph.
Of course, that speed was probably not officially certified.