We’re four installments in, and the Grassroots Motorsports Club Spec Mustang has finally hit the track at a Tire Rack SCCA Time Attack Challenge weekend.

Let’s back up.

In a multi-part video series, Grassroots Motorsports is following along as GRM’s Video Editor Chris Tropea, under the watchful eye of GRM’s Tech Editor JG Pasterjak, preps an S197 Ford Mustang for SCCA’s Club Spec class, with the ultimate goal of making it to the Oct. 23-25, 2026, Tire Rack SCCA Time Attack National Championship at Eagles Canyon in Decatur, TX, and (hopefully) claiming a spot on the podium.

Club Spec is SCCA’s build once, compete everywhere series of classes, where one set of rules span SCCA Autocross and Time Attack, allowing someone to own a car that’s not only drivable on the street, but also competitive in class. Club Spec currently has classes for the NC MX-5s and early S197 Mustang GTs, with 718 Porsche Caymans and Boxters on the way in 2027.

GRM’s video series began with an introduction, then jumped into interior mods followed by a differential install. With much of the build complete, part four in the series takes the car to Carolina Motorsports Park (CMP) for the June edition of the Tire Rack SCCA Time Attack Challenge, where Tropea co-drove with Pasterjak. This was Tropea’s first time at CMP and his first time lapping a racetrack for a time; Pasterjak, meanwhile, hadn’t been to this particular track for 20 years. Needless to say, there was a learning curve.

There were also lessons when it came to the car. They resolved a fueling issue early on, and also discovered the car’s cooling system could use some beefing up.

How did the car and drivers do? Check out the video to find out.

Image courtesy Grassroots Motorsports YouTube Channel

We’re now knee-deep into the “Who Will Win the Solo Nationals?” series, which culminates in the video game themed Sept. 7-11, 2026, Tire Rack SCCA® Solo National Championships in Lincoln, NE, where we find out just how right (or wrong) you were in these polls. And let’s be clear, the ONLY reason we hold the Solo Nationals is to prove or disprove everyone’s ability to make predictions.

Having already published polls for Stock, Solo Spec Coupe/Street Touring, and Street Prepared, it’s time to jump into everybody’s favorite category: Street Prepared.

Yeah, yeah, yeah…I called Street Prepared “everybody’s favorite category” yesterday, too, but this time I’m serious.

Why is this one everyone’s favorite? XP hosts Datsuns, Lotis (Lotuses? Loti?), and classic Porsches; CP showcases rowdy Americana; EP is home to the tuner Civic scene; and DP and FP offer a place to play for people who have a personal vendetta against windshields.

Since I began this article ripping off the Street Prepared article, I may as well do the same at the end…

Below are polls for all the classes in Street Prepared, where you can vote for who you think will win. As we said in the first installment of this series, choose your character below, lock in your pick, then hit “submit.” Next, scroll back up on the page where you’ll find a “See previous responses” link. Tap that and discover how your favorite drivers are faring in the polls.

You can also refresh the page and vote again and again. The only limit to the number of times you can vote is how much you’re willing to risk carpal tunnel syndrome.

Photo by Jeff Loewe