In 1999 the small-tire world was turned upside down when the NMRA Ford Nationals brought true-10.5-inch tire racing to national prominence. It became known as the 10.5-inch Tire Freak Show and the standards of true 10.5 racing were set in a class known as Super Street Outlaw. Racers, manufacturers, and technology were pushed to the limits, as SSO became the proving grounds for the latest in small-tire madness. Seven-second runs came within two seasons and each performance plateau left people wondering how fast can these racers go on that little tire? A lot has happened over the last 21 years.
Super Street Outlaw wasn’t the only class on small-tires but at one time it was the biggest and its popularity helped grow the small-tire market into the largest segment of drag racing. From mildly modified street cars racing at local events to X275 and similar classes, their roots are in the Freak Show. Twenty-one sessions later and VP Racing Fuels/Mickey Thompson Street Outlaw is being reorganized for the second time in its storied history.
Its first shake-up was in 2012 when the class name switched to Street Outlaw and a freshened set of rules helped bring it closer to the larger market that the class helped define. At the time, NMCA Muscle Car Nationals adopted an identical set of rules and racers had 10 events to attend and could chase a championship in either one.
In 2019 NMRA and NMCA officials — led by former Tech Director Lonnie Grim and Rollie Miller, ProMedia’s head honcho in the event division — worked with X275’s John Sears to closely align the two classes. “Lonnie and I spent hours on the phone discussing the combination of X275 and Street Outlaw,” said Sears.
“It was important for us to work with Sears with Street Outlaw and also get our Xtreme Street and Renegade categories inline with his Ultra Street rules,” Miller added. “They aren’t identical but any racer who competes in X275 or Ultra Street can roll into NMRA and NMCA events without having to add a pound of weight or make any other changes.”
The two groups also agreed to utilize the NMRA/NMCA format for laying out the rules in writing. “The format is very much like Street Outlaw and NMCA/NMRA, but we were able to streamline them so they weren’t so cumbersome and wordy,” explained Sears. The combination of the two classes was first announced before the Performance Racing Industry Show. The two classes combine the looser nature of the NMRA/NMCA chassis rules that allows any rear suspension system with factory frame rails and the power adder sizing of X275.
The major difference on the chassis side is that in X275 there is a 50-pound penalty for a four-link suspension but not in Street Outlaw. The front-strut-tower rules vary slightly and that mostly applies to late-model cars with a MacPherson-style strut setup. In regards to engine combinations, the power adder sizing of the centrifugal superchargers and turbochargers are a direct crossover as well as the billet head or billet block rules. The tall-deck billet blocks normally found in Street Outlaw are also included in the X275 rulebook for 2019.
The only major differences are both sides had an engine combination that they wanted to have a “wait-and-see” approach before approving. For X275, the 5-inch bore space/nitrous combination that is allowed in Street Outlaw isn’t in the rules. In Street Outlaw, the tech group wanted to see how it shook out with the 8-71 Roots-supercharged after the weight addition in late 2018 and the controversy that surrounds the setup.
NMRA/NMCA Street Outlaw offers six events in each series for racers to chase a championship and the coveted Nitto Tire Diamond Tree ring. If championship aspirations aren’t on the to-do list, the near-identical rules gives racers the chance to participate in one of the events when it comes to their home track. Local or national level, the world of 275 Radial racing is booming with plenty of opportunities to get on track in 2019 and beyond.