Let’s skip the chitchat and get right into it. The rush is on to get this Chevy Sonic RS ready and show-worthy for SEMA. Plus, it actually has to run and perform before the show, so the pressure is really on.
For the interior, the plan is to give it a club racer feel so it’s just at home at the racetrack as it is on the street. With that in mind, a rollbar was a crucial piece to the puzzle. It not only adds an important level of safety but also improves overall chassis rigidity and allows for easy and proper installation of race harnesses.
There aren’t any bolt-in options for the Sonic so we had our local fabrication shop, Centerline Motorsports, weld us up a custom half-’cage. Using chromoly steel, Centerline ensured the weight was kept to a minimum, while the structure met most sanctioning body standards. The result is a rollbar that will function as good as it looks.
| Project Chevrolet Sonic RS - Stock On The Outside, Party On The Inside
A custom rollbar is the ideal solution for any dual-purpose street/track car. Painting it with the interior can be a bit daunting, but the results are worth the extra effort.
Centerline also ensured that we could fit the interior in and around the rollbar, which was crucial in terms of maintaining street appeal. The job required gutting the side impact airbags, but they won’t be needed anyways.
As you can imagine, painting a rollbar with half the interior in place requires a ton of masking. As the photos show, we spent a long time ensuring that there would be no overspray inside the car, but boy was it a tiresome process. Remember to lay down a good etching primer before you paint the bar, otherwise it will chip very easily.
| Fitting the interior around the rollbar requires gutting the side impact airbags, but we’ll take a rollbar over them any day.
Onto the bottom holders, a set of Recaro Sportster CS seats are the perfect blend between style, comfort, and aggressive bolstering. If there’s one seat that does it all very well (with little compromise), the Sportster CS is it. Aggressive hip and side bolsters provide ample support and keep you planted in the seat, while provisions for race harnesses make the Sportster CS worthy of track duty. The reclinable function also makes it easy to get comfortable for long rides. At first, we weren’t actually sure if these would suit the Chevy Sonic, but the more we live with them the more we like them. They aren’t as supportive as full bucket seats, but if that’s a concern we can always address it in the future.
| The differences are obvious, right? Recaro’s Sportster CS seat provides the best of both worlds—great support with good comfort.
| Project Chevrolet Sonic RS - Stock On The Outside, Party On The Inside
Mounting the seats requires seat rails from Planted Technology. They are one of the few companies dedicated to producing seat brackets for less common applications, like the Chevy Sonic, and the quality of the pieces is top tier. The brackets slide into place like OEM, which if you’ve installed rails before isn’t always the case. Griffin Motorwerke was kind enough to supply us with a set of Recaro sliders; they are a must if you want any type of back and forth seat adjustment. Griffin actually stocks and sells the entire Recaro catalogue (and many other brands), so if you’re in the market for seats, rails, and so on, odds are they have it in stock and competitively priced.
Planted Technology offers bolt-in seat brackets that make installation a breeze. Griffin Motorwerke supplied us with the Recaro sliders, a must in this application. Lastly, you’ll have to spend a bit of time transferring over such stock items as seatbelt latches and some wiring to retain use of the stock seatbelt system.
As we’ve mentioned countless times in this magazine, a race harness is an integral part of keeping oneself snug and tight in a seat during track outings. Not only that, but it provides more protection than a standard three-point seatbelt. There’s one brand that has always stuck with us, and they also happen to be an OEM tier supplier and motorsports provider of seatbelts, so it’s safe to say they rank among the best in world. Envision Auto Imports hooked us up with our Takata Racing four-point belts in record time, and now we have a proper belt setup that’s found in most top race cars. Safety is priority number one, so never, ever skimp on a harness and look for FIA standards requirements on all belts before buying them. It’s good to know all Takata Racing harnesses meet and exceed those standards.
| Project Chevrolet Sonic RS - Stock On The Outside, Party On The Inside
Takata Racing harnesses are arguably the best in the business, and with the aid of our rollbar and Recaro seats, fitting them is a breeze. Make sure to properly wrap the harnesses on the rollbar. If you’re not confident with it, leave the job to a pro.
Completing the interior are two fundamental gauges that every turbocharged engine should have, boost and water temp. The latter is especially important on the Sonic since it doesn’t have a factory temperature gauge. Instead, there’s just a warning light, and we’re not about to trust that on the track. That’s why a 60mm Advance CR Defi water temp gauge now resides just beside its boost counterpart. These two gauges are placed well within eyesight and have peak, warning, and replay functions, so there’s full assurance the engine’s vitals are always on watch.
Speaking of, you can expect some tasty performance parts on the way to help our little 1.4L turbocharged 4-cylinder pump out some more jam. There are also hard-core body mods in store. We’re just getting started here, but this project is at full speed ahead.
To keep tabs on boost and water temperature, a set of Defi Advance CR gauges were mounted just to the right of the factory gauge cluster. By coincidence, the Defi visors are almost identical to the stock cluster, giving them a very OE-style look in the cockpit.