The Ford Mustang Boss 429, a real heavyweight of its time, was Ford’s bold attempt to challenge the Chrysler 426 Hemi on the NASCAR tracks. With an engine so big, it needed a trunk relocation for the battery—because who needs trunk space anyway? Kar Kraft had to re-engineer the Mustang just to fit this beast under the hood. The result? A 375 hp engine that laughs at its own rating, easily roaring past 600 hp with tweaks. The Boss 429 is a muscle car icon, proving that size does matter!