Probably the most raucous sports car I ever heard was when Herbert Muller raced a Ferrari 512 spyder in the 1974 Can-Am series, I got to see, and hear it at Mid-Ohio. The sound of that thing powering out of the Keyhole onto the back straight at MO was fantastic.
But probably the most ridiculous sounding racing cars I ever saw in person were the early-mid seventies USAC Dirt Champ cars that used the Ford four cam engine developed for Indy. The sight & sound of those vicious devices bombing around places like Terre Haute, or the Indiana State Fairgrounds, driven by the likes of AJ Foyt, Mario Andretti, the Unser bros., Johnny Rutherford, Gary Bettenhausen, etc. was something special. I got to see them many times during that era, including in 1974 when Mario took the USAC title, in his last year on dirt. The Fords were pure screamers, while the four banger Offy's made more of a ripping fabric sound, a great combination in battle.
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