Editor’s note: Bozi Tatarevic is a professional racing mechanic and pit crew member. He will provide technical analysis for NASCAR.com throughout the 2022 season.
The NASCAR Next Gen car has brought an incredible amount of street-car relevance to the latest generation of Cup Series cars with the implementation of symmetric bodies and the focus on OEM-specific design elements.
Cars on track will look much like what we can find in the showrooms, and that will also extend to the shops as the new composite bodies offer individual panels much like a production car – a departure from the large pieces of sheet metal used in recent generations of the Cup car.
Making the body pieces out of composite materials was only one step of the Next Gen process. The attachment methods analyzed below are going to be very important for races like Sunday’s Daytona 500 (2:30 p.m. ET, FOX, MRN/SiriusXM NASCAR Radio), which will have multiple sessions on track before the main race. We are likely to see teams bringing spare parts versus the entire spare cars they might have brought in years past as they can unbolt certain sections if the vehicles are damaged in practice, or more likely in one of the Bluegreen Vacations Duel races as those often end up being as action-packed as the main race itself.
Like the outgoing car, the Next Gen car starts as a chassis. The difference now is that it comes in multiple pieces that are bolted together versus one piece that is welded together. The chassis consists of a center section with front and rear clips bolted to it and bumper supports bolted to those pieces. Once the chassis is assembled, there are brackets that are installed with studs on them that are intended for body mounting, as highlighted in the illustration above.
The first layer of panels that bolt up to the car are the closeout panels, which are not visible on the outside but are intended to seal the center section from the outside along with separating sections like the wheel well from the fuel cell area. These are roughly the equivalent of internal door panels and wheel well liners on a production street car. They help to separate the driver from outside elements and are also used for secondary purposes in some cases, like the pieces at the front corners of the car which have ducting to cool down the exhaust.
In addition to the closeout panels that get mounted on the chassis before the full body is assembled, there are also pieces of protective foam that get mounted on each side of the car. The purpose of this foam is to absorb energy in the case of a crash in order to make the center section safer for the driver.
Some of the studs that we see sticking out of the top of the chassis in the illustration above are intended for the greenhouse, which is the top part of the car that contains the pillars, windows, windshield and roof. We can see where the stud from the front left corner of the car matches up to the spot on the A-pillar of the greenhouse, which is marked in red. The greenhouse assembly is a piece that is shared among all the cars and is built with driver safety and comfort in mind as it contains items like the roof flaps that are intended to slow the car down in case it turns, along with ducting for driver cooling. We even got a view of the chassis and the greenhouse being installed onto the chassis in a Corey LaJoie paint scheme reveal video last week.
She’s ready to go out on that race track. She’s gonna be perfect. Can’t thank my friends at @bar_built enough for their continued support. pic.twitter.com/BWffZMQiVG
— Corey LaJoie (@CoreyLaJoie) February 10, 2022
Once we move down to the external body panels of the car, things start to look even more familiar and much more like a street car than what we’ve been familiar with over the last few years. Instead of a large piece of sheet metal for the side we now see individual composite components for each piece. In the same theme as their production car equivalents, we see individual pieces for the bumpers, fenders, hood, doors and quarter panels.
The system of flanges and fasteners used to connect the body panels together is so close to what we see on production cars that a standard body shop would be able to assemble these components together. Most production cars feature a system of hidden flanges and captured nuts behind body panels in order to fasten them together and as we can see in the illustration above, the Next Gen car follows a very similar system.
The closeout panels like the fender liner mount to the car in a similar way and attach to nut plates, which are installed in the body panels behind the liner. The hardware for the fender liners is visible which allows for quick removal in case a component behind the liner needs to be accessed after the car has been assembled. These panels are assembled by pretty standard hardware and are mainly held on with 1/4-28 flat head socket cap screws for the fender liner.
The body is finished off with the installation of a variety of smaller pieces up top along with aerodynamic components such as the spoiler. The remaining pieces are on the bottom and they form the assembly known as the underwing. The underwing is a flat floor that completely encloses the bottom of the car; it starts with the splitter at the front leading all the way to the diffuser in the rear. Much like many of the other body components, the pieces of the underwing mount to the chassis using 1/4-28 flat head socket cap screws.