1971 Dodge Demon - How To Buy A Used Race Car

Bob Bondurant once told us that last year's race car is the oldest car in the world. The reference to physical age is clearly a metaphor for the evolution of technology in road racing, but there is another meaning: Buying last year's race car is cheaper than building your own. If you don't have a specific vision for how the car needs to look, you can get a used race car for a third of the price of doing it yourself. As with anything, there are traps. The wrong 'cage or wrong combination of parts can undo the savings and stick you with junk. We recommend going to your local racetrack and hiring the tech inspector or a known chassis builder as a consultant who will go with you to look at race cars. That and following the advice below will keep you from getting a bad deal.

The 'Cage

A rollcage is required for any full- bodied drag-race car with an unaltered firewall and floor that runs quicker than 10.00 or faster than 135 mph in a quarter-mile. Convertibles or open- bodied cars require a 'cage if quicker than 10.99. The rollcage must have a chassis inspection every three years and have an NHRA sticker before it will pass tech, making it the most important part of the car. If it is improperly installed, is the wrong size, or is not built for the speeds you want to run, it has to be removed from the car and replaced. We spoke to NHRA tech inspector Pat Cvengros about what to look for before you make the deal and had him inspect our chassis for certification.

"The most common problems are missing D-bars and the main hoop or A-pillar bars that are the wrong size or thickness," Cvengros says. The main hoop is the portion of the 'cage that connects the frame together and protects the driver from a rollover. It needs to be placed above and behind the helmet when the driver is belted into the car and must include a crossbar that is no more than 4 inches below the driver's shoulders. The D-bars are welded to the main hoop and vertically angled toward the center of the car. They are required only when the main hoop is welded to plates on the floor instead of to the car's original frame or a crossmember. If the D-bars are incorrect, they can be added or fixed easily. The main hoop also needs to have rear braces that must be a minimum of 30 degrees from vertical and welded in and a door bar that passes the driver at a midpoint between the shoulder and elbow. These parts constitute a rollbar for 10.00-and-slower full-bodied cars and form the basic structure for a rollcage. Cars faster than 10.00 need A-pillar bars that run along the roof of the car and connect to the sidebar at its base and along the top of the windshield. These parts complete the structure and protect the driver from an impact from any angle. Both the A- pillar and main hoop need to have a minimum of 1-5/8 inch od with a material thickness of no less than 0.083 inch for chromoly or 0.118 inch for mild steel. Fixing missing or incorrect D-bars is easy, but if either the A-pillar bars or main hoop are too small or too thin, they need to be totally removed and replaced. That's a deal breaker.

Welds And Workmanship

All the monkey bars in the universe aren't going to save you if the welds break. The NHRA requires that the welds not be porous (aka bird poop), and they can't be ground down or caked with Bondo and painted. They also require chromoly tubing to be TIG-welded and mild steel to be MIG-welded. When looking at a potential race car, be sure to have the welds checked by someone who knows what they are looking at.

Finally, take a look at the structure as a whole. A good rollcage has bars that are as high as possible in the car and tied into the load points of the suspension. It will also be built as far forward as possible with a front crossbar that is behind the dash and up near the cowl. Although not required by the rules, tube gussets and crossmembers keep the car rigid and the suspension behavior consistent while further protecting the driver in the case of side impact. Bring a guy, take your time, and buy a good car. Then take your car to a track or call the NHRA to have a chassis inspector sent out to certify the chassis.