Project Sonic Boom - Modified Magazine

Project Sonic Boom - Track Spec Version 1.0

With almost the entire interior in proper track/street spec order, the stock exterior of the Sonic RS was in serious need of similar treatment. The goal wasn't to go overboard with the styling because in all fairness to GM, it's a decent-looking hatchback. Instead, the plan is to beef up the car and give it that aggressive, raw, track-car appeal while maintaining its street cred.

The task seemed simple in theory but hard to execute in real life because time was not on our side. The schedule called for a scant seven days for the bodywork to be done, which seems like a lot to bolt on some fender flares, front ducts, and a splitter—but it's quite the opposite. Especially when you realize that off-the-shelf flares won't work. I tried Datsun 240Z and universal flares, but the Sonic's fender lines didn't match up at all. Having to cut and hack them would take just as much time as a set of completely custom ones, which in the end would fit better and be built exactly to my specs.

Project sonic boom preliminary sketches   |   Here are some preliminary sketches ML24 came up with. You can see the original design at the top and further refined at the bottom as well as a few styles of fender flares.

Through the guys at Cyrious Garageworks, I got to know Matthew Law of ML24 Designs. Matt designed a full widebody kit for Pat Cyr's Scion FR-S drift car in a short amount of time, and his ability to take a rendering and make it into a real-world product is what made him an ideal partner for this project.

After meeting up and looking at the renderings Jon Sibal had originally drawn up, Matt went to work to create his own rendering. From there, we narrowed down a design I liked, and finally a 3-D model drawing was done up. Matt uses 3-D as an aid to actually building the real parts. This process cuts down on a lot of the guesswork that is usually involved when building custom one-off fiberglass pieces.

Project sonic boom raw and unfinished mold 01   |   Project Sonic Boom - Track Spec Version 1.0 Project sonic boom raw and unfinished mold 02   |   Here you can see what the raw and unfinished mold looks like. 20HZ takes these raw pieces and turns them into a polished product that you’d never guess started life like this.

To complete the physical bodywork, ML24's partner 20HZ Audio Sound & Security was tasked with the challenging job of fitting and finishing everything in seven short days. Don't let the name fool you; Frank Valenti and his team are experts and true artists with fiberglass. Watching them take rough fender flare molds and shape them into what you see on the car now (in such little time) is a feat few people can do well. While the flares, front splitter, and foglight delete panels with APR NACA duct vents were all custom jobs, the side sills from Shine Auto Project that are intended for a Mazda RX7 fit the Sonic with zero modification necessary. Sometimes you just luck out and, thankfully, we did because everything came together at the very last minute.

We all know wheel choice is critical, and part of the reason why fender flares were added to the Sonic is to broaden the wheel selection. There will actually be two sets of wheels and tires for the Sonic, one dedicated for the street and the other for track duty. A recent addition to the Volk TE37 family is the classic-styled TE37V. This 17-inch wheel provides more dish than a standard TE but still weighs in at a scant 17 pounds in 17x9 flavor. The tire of choice is one of my favorites for the track, the Toyo R888. Being an R-compound that is DOT street legal means you can drive it to and from the track, where it provides ample amounts of grip and never fades out, especially on a car such as this. As for the street setup, well why ruin the surprise? You'll have to wait till a future issue to find out what it is.

Project sonic boom flare   |   It was a necessity to have the flares bolt on and off, so that meant some extra work adding provisions for screw holes. The result is a flare that can be removed with ease.

You're probably wondering how those TE37Vs fit on the Sonic when its bolt pattern is an uncommon and very limited 5x105. Thanks to some custom 20mm bolt-on hub adapters from Novustech and some trimming of the original wheel studs, our bolt pattern is now a much more appealing 5x114.3. Even with the 20mm addition and +20 offset on the TE37Vs, the setup is lacking in the flush department. Another 10 or 15 mm outward and it'll be functional while looking proper, so expect to see that happen in the very near future. The 4x4 ride height will also be brought back down to earth, but at the moment, the one-off front splitter is too precious to ruin before SEMA, so no more low.

Speaking of which, there is a lot to still get done before this car heads off to the show, and that means there's no time to spare. Next up, engine mods and some help in the braking department, plus a million and one little details to make the Sonic RS one legit and badass hatchback.

Project sonic boom trim stock metal fender lip   |   This photo shows the stock metal fender lip that had to be trimmed to ensure proper wheel fitment. If this car didn’t actually see real street and track duty, then you could get away with leaving it—but that’s not the right way to do things. It’s a scary task to cut up stock sheetmetal, but it needs to be done! Project sonic boom foglight delete panels   |   The foglight delete panels with APR NACA ducts free up some weight, ridding the Sonic of its foglights, but the real reason for them is they will eventually be ducted to the wheelwells for cooler airflow to the brakes. Project sonic boom 20mm hub adapter 01   |   Project Sonic Boom - Track Spec Version 1.0 Project sonic boom 20mm hub adapter 02   |   Adding a 20mm hub adapter that converts the bolt pattern from 5x105 to 5x114.3 required trimming the studs so they wouldn’t interfere with the back of the wheel. Not an ideal practice, but there’s still more than enough thread left for the lug nut to hold on to. Project sonic boom sonic RS new look   |   It’s amazing that in seven short days, this was all accomplished. The Sonic has taken on a completely different look and style. Project sonic boom sonic RS left side view   |   The Volk TE37V wheels wrapped in Toyo R888 tires look to be the perfect style and aggressive fit for the Sonic’s new body lines.