The dirt world has some truly awesome pieces of engineering. From the backyard-built Bombers to the always-impressive winged Sprint Cars, dirt racing at any level is ultra exciting.
When it comes to the sport's roots, much of the significant history is based around the Modifieds. Modified stock cars are a class of racing that has evolved over the last 70-plus years, going back as far as the end of World War II. Before and during the war, Midget racing ruled the short tracks of America. When the troops returned from overseas, service men trained in engineering and fabrication were looking for a fix for their cravings to build things, and race cars were the perfect outlet.
In the beginning, the term modified referred to the engines in the cars, as cylinder boring was permitted so displacement could be increased. The cars were vehicles people used simply to get around, or cars found in junkyards. In the 1940s-1950s, a Modified stock car was just that—a stock automobile that was modified. The glass was removed, a rollcage was installed, and the engine's performance was increased. This is where the class got its name.
The '60s and '70s were significant decades for Modifieds. Until this point, the cars still looked like cars. The '60s is when the car builder's innovation started to take a huge turn. Mixing and matching components became more and more popular. It wasn't uncommon to see a Ford body on a GM frame with Mopar brakes and a Corvette engine. At the point the bodies themselves began to take on a new look. Wheelwells were enlarged for tire clearance, but during this time, racers began channeling and lowering the bodies, which gave the cars a lower, more aggressive look. Racers also began removing the front fenders all together, which is now a signature feature of a Modified.
The '70s saw the introduction of fabricated tubular chassis, as well as smaller, subcompact cars like the AMC Gremlin and Ford Pinto, and those bodies fit perfectly over the Modified chassis. This soon evolved into hand-fabricated sheetmetal bodies, which loosely resembled production cars. As technology has evolved, these bodies and chassis have become advanced with new suspension and aerodynamic innovations, that are still evolving and improving today.
Today, Modifieds are still one of the most popular classes in short track dirt racing, with the Big Block Modified sitting at the top of the food chain. While these cars are mostly found in the Northeast, they start the season in Daytona, Florida, for Speedweeks and The Dirt Track at Charlotte, North Carolina, hosts the Super DIRTcar Series finale each year.
These monsters are wheeled by some of the best racers in the country. At the top of that list is Brett Hearn. His stats are so impressive that they almost seem unbelievable.
Hearn has compiled more than 75 series and track championships, more than 800 wins, and loads of other accolades. This solidifies Hearn as one of the most accomplished drivers in circle track racing wheeling everything from Modifieds to Sprint Cars. Competing in 95 races in 2012, Hearn finished in the top spot 20 times. Regardless of where, if Brett Hearn is on the track, he is always a threat to win.
When it comes to Modifieds, the differences between big-block Mods and 358 Mods can be rather subtle. Billy Dunn routinely races both, and he took some time to explain some of the difference to us.
"The cars are exactly the same," explains Dunn. "With the big-block cars you can't use all of the lightweight drivetrain components. The big-blocks make so much power that they don't have the same durability."
He went on to tell us how each car's amount of horsepower dictates the driving style and setup. "Small-block Modifieds are more momentum based," Dunn tells us. "You almost have to drive them like a go-kart. The big-block Modifieds have so much more horsepower, a lot of times you don't use all of the power you have. The setups are fairly similar. We run the small-block cars on the freer side to keep the momentum up. With the big-block cars you need as much grip as you can get. They (big-block Modifieds) are a lot like a Sprint Car. You have more power than you can use, and they are a lot of fun to drive!"
As this story comes to completion, The UNOH DIRTcar Nationals, presented by Summit Racing at Volusia County Speedway is rapidly approaching. The first event of 2013 for the Super DIRTcar Series, which promises to be ultra exciting, will take place on February 20-23.
|Big-Block Dirt Modified Specs (Super DIRTcar Series)
||Max displacement 467ci
||Carburetor only—four-barrel Holley 950-1,050 cfm
||Approximately 160 mph (at New York State Fairground at Syracuse, NY)
||Two-speed transmission—one reverse quick-change rearend
||Beltdriven dry-sump (approximately 13 qts.)
||VP fuels racing gasoline
||74-inches min. to 86-inches max.
||2,500-pounds min., with driver
||Fabricated chassis—1018, 1020 steel
||Mostly torsion bar rear—coil spring (coilover) front
||Approximately 5-inches front, 6-inches rear frame heights
|Minimum Ground Clearance
|Right Rear Tire
||Aluminum (bead lock)
||Power steering (worm and sector)
||Four wheel hydraulic disc brakes (no power assist)