NHRA Classes Overview
Top Fuel, Funny Car, and Pro Stock are just three of the more than 200 classes of vehicles featured in NHRA competition. Those classes are grouped into 15 categories, or eliminators, each governed by NHRA rule makers. Class eligibility is based on various requirements and specifications, including type of vehicle, engine size, vehicle weight, allowable modifications, and aerodynamics.
The four Professional categories are Top Fuel, Funny Car, Pro Stock, and Pro Stock Motorcycle. They, along with Top Alcohol Dragster and Top Alcohol Funny Car, the three "Super" classes – Super Comp, Super Gas, and Super Street – and Pro Mod feature a single class of vehicle in heads-up competition. Comp, Super Stock, and Stock are made up of a variety of classes and use a handicap starting system to equalize competition. Top Dragster and Top Sportsman feature a single class of vehicle in bracket-style competition.
Among the fastest-accelerating machines in the world, these 7,000-horsepower dragsters can cover the dragstrip in less than 3.8 seconds at more than 325 mph. Top Fuel cars are 25 feet long and weigh 2,320 pounds in race-ready trim.
Similar to their Top Fuel counterparts but with a shorter wheelbase and a carbon-fiber body that loosely resembles a production-based automobile, Funny Cars, or “floppers,” routinely run in the 4.0s and can exceed 315 mph.
Often called “factory hot rods” because of their resemblance to production-based cars, Pro Stockers can run in the 6.4s at more than 210 mph. They can rev to more than 10,500 rpm and make in excess of 1,300 horsepower.
Pro Stock Motorcycle
These highly modified vehicles, which can run under 6.8 seconds at more than 195 mph, feature a purpose-built tube chassis and a lightweight, aerodynamically enhanced replica of original bodywork.
Top Alcohol Dragster
Top Alcohol Dragsters may look like Top Fuelers, but they have significant differences. They may use a supercharged methanol-burning engine or an injected nitromethane combination. They can run in the 5.1s at more than 280 mph.
Top Alcohol Funny Car
Similar in physical appearance to their nitro-burning Funny Car counterparts, Top Alcohol Funny Cars are restricted to the use of methanol fuel and have three-speed transmissions. They can run in the 5.4s at more than 265 mph.
No category in NHRA competition features more variety than Comp. Each of the 88 classes is assigned an index based on what a well-built car should run, and races are handicapped according to those indexes.
Super Stock vehicles may look like ordinary passenger vehicles, but they are highly modified race cars. Entries are classified using factory shipping weight and horsepower and compete on indexes. The breakout rule is enforced.
Stock cars are similar to Super Stockers, but rules regarding everything from engine modifications to body alterations are much stricter. Virtually any car is eligible to compete, and entries are classified using factory shipping weight and horsepower.
The quickest of the heads-up Super classes (8.90 index) is composed primarily of dragsters. Most cars are capable of running well under the index but use electronic aids to run close to the index without running quicker than it, or breaking out.
Super Gas entries, which run on a 9.90 index, are primarily full-bodied cars and street roadsters. No dragsters or altereds are permitted. As in Super Comp, competitors use electronic aids to run as close to the class standard without going under.
Racers compete on a fixed 10.90 index. All vehicles must be full-bodied cars and weigh no less than 2,800 pounds except for six-cylinder cars (2,000) and four-cylinder and rotary-powered cars (1,200). Engine and chassis modifications are virtually unlimited.
Competitors in these full-bodied entries may choose their own dial for eliminations, generally from 6.00 to 7.99 seconds. Full Tree starts are used, and the breakout rule is enforced. Cars can run in the sixes at more than 200 mph.
Competitors in these open-wheel entries may choose their own dial for eliminations, generally from 6.00 to 7.70 seconds. Full Tree starts are used, and the breakout rule is enforced. Cars can run in the sixes at more than 200 mph.
The NHRA Pro Mod Drag Racing Series presented by ProCare Rx runs at 10 NHRA Full Throttle events. An eclectic mix of vehicles, from ’41 Willys coupes to ’63 Corvettes to late-model Ford Mustangs and Dodge Vipers, can run in the high fives at more than 250 mph.