At the 2017 SEMA show, Mopar released the Hellcat engine into the wild, so to speak, announcing that it would sell crate ?cats to anyone with 15 grand and a skateboard large enough to strap it to. Also at SEMA, the Ringbrothers of Spring Green, Wisconsin, showed a car that could serve as the veritable model for Mopar?s new adopt-a-Hellcat program: a 1972 AMC Javelin AMX called ?Defiant,?  built for antifreeze giant Prestone. It’s powered by a Hellcat Hemi tuned by Wegner Motorsports to an utterly feral 1036 horsepower. The car looked amazing up on the stand, but we all know that cars like this always look (and sound) better on the street, so when we were offered a quick spin in the beast at Point Dume, in Malibu, California, we said, ?Hell, yes.?   Based on a 1972 AMC Javelin AMX that is said to have been trolling the Rings? hometown for decades, Defiant is described by its builders as ?arguably the wildest custom vehicle ever crafted? by the Ringbrothers team. Not only does it host a Hellcat with four-figure output under its carbon-fiber power-dome-on-a-power-dome hood, but the Ringbrothers have gone to extraordinary lengths to perfect the Javelin?s styling and stance.

If Defiant doesn?t look quite like Javelins you remember, that?s no accident: Ringbrothers moved the front axle forward a full 6.5 inches, then crafted all-new front bodywork out of carbon fiber, complete with the Javelin?s distinct front fender humps in their relocated position. Another differen...