Chrysler’s unibody, the skeletal structure of every Mopar muscle car from 1964 to 1974, was quite the feat of cost-effective engineering. Every inch of sheet metal from roof skin to floor pan was designed to work together to create a cohesive culmination of rigidity.

In stock form, that construction easily handled Hemi-level torque and more. However, as power levels have increased over the last several decades, those unibodies have been stressed at levels the likes of which were never considered some fifty years ago.

USCT Motorsports has taken it upon themselves to make sure your Dodge or Plymouth doesn’t twist into a pretzel with a full lineup of chassis stiffening components. The newest addition to that ensemble is an inner rocker sill brace set (P/N USCT1M2048) for 1966-1970 B-bodies.

Computer-designed, CNC-cut, die-stamped, and precision-bent, these braces act like a pair of backbones along the outer perimeter of the floor pan.

In an arrangement similar to the factory E-body convertible stiffening technique, they fit inside the rocker box to be completely hidden yet highly functional. Removal of the outer rocker is necessary but, with these cars coming up on the five-decade mark, a great many of those rockers are due for demolition anyway.

Once welded in, the braces form a triangulated enclosure between the front and rear wheels to help add rigidity to one of the weaker structural sections of the car. Couple them with the full gambit of a USCT chassis kit and you’ll have yourself a rock-solid ride.