Today, in my Boss 302 Mustang, I was in and out of traffic with a new Shelby GT-350. It has (I think) a 5.2-liter engine with a flat-plane crankshaft. My car's heavily prepped 5.0-liter Coyote engine makes a very nice rumbling V8 sound, but the flat-plane 5.2 makes a different noise altogether, like the old Ford-Cosworth V8s used in Indy-car racing back in the day. Gr-r-r-r-r-r-r-r-r-r-r-r!