One of several Chevrolet Sonic Z-Spec concepts that will be revealed at the upcoming SEMA Show.

The annual aftermarket extravaganza commonly known as the SEMA Show is typically an orgy of muscle, makers like Chevrolet and Ford revealing tricked-out Camaros and Mustangs making astronomical amounts of horsepower and torque.

Not so this year.  True, you’ll still find plenty of hot rods and muscle cars on display but there’s a surprising emphasis on smaller, more mundane products designed to show they aren’t the stone ponies of decades past.  So, Chevrolet will be showing up at the Las Vegas Convention Center with a pair of downsized offerings that could cast a much more favorable light on the new Sonic and Cruze models.

“The heritage of Chevrolet cars like the Corvette and Camaro is being expressed in smaller packages for the next generation,” said Chris Perry, vice president, global marketing and strategy for Chevrolet. “The Sonic and Cruze concepts demonstrate that performance comes in all shapes, sizes and displacements at Chevrolet.”

A second SEMA Z-Spec concept.

The Cruze has already shown it can click with American buyers – jumping to the top spot on U.S. sales charts in recent months, the first time a Detroit maker has toppled its Japanese rivals on the passenger car side in decades.  The Sonic still hasn’t been tested.  It’s the replacement for the largely unloved Chevy Aveo and though it’s also a Korean design the new 2012 subcompact is being produced in the U.S., at a plant in suburban Detroit.

Chevy is intent on showing that these small cars are more than just basic transportation.

With the first of two Sonic Z-Spec concepts, shown here, Chevy designers took a turbocharged five-door and added concept Z-Spec accessories including ground effects, spoiler, grille and graphics package. The Torch Red exterior is finished off with concept Z-Spec 18-inch wheels. Inside, the Cobalt Red cabin features custom trimming, including perforated black suede seat inserts, a concept Z-Spec sport pedal kit, sport shift knob and a racing-style flat-bottom steering wheel.

A look at the Z-Spec concept's customized interior.

A second Z-Spec, on the jump page, is finished in Flat White with Torch Red accents, and a more aggressive ground effects package, unique grille, rear spoiler and graphics package. It rides on Z-Spec concept 18-inch wheels and also includes a re-trimmed interior with Z-Spec sport pedal kit, Z-Spec sport shift knob and a flat-bottom steering wheel.  The factory 1.4-liter inline-4 engine is complemented with a high-flow exhaust and the concept car gets upgraded brakes and suspension components.

The SEMA show will see at least two more Chevy-customized Sonics, as well as a Cruze wearing the Z-Spec badge – and featuring ground effects and 18-inch wheels – as well as the more subtle Cruze Dusk.