In 2002, the Honda Challenge racing series was created on the East Coast as a competitive racing venue for competitors with Hondas and Acuras. The main intention of the series was to provide a place for competitors to race their "swapped" vehicles which did not currently fit in any other series rules competitively. In 2003, the Honda Challenge series became a national NASA class with multiple regions including East Coast (ECHC), West Coast (WCHC), Mid West (MWHC), South East (SEHC), Northwest (NWHC), Texas (THC), and Florida (FLHC). The Honda Challenge series currently has competitors in all of NASA's 11 regions across the country. 

There are five progressively slower classes in the Honda Challenge series, beginning with H1 and moving through H5. The fastest class, H1, includes "hybrid" cars equipped with engines not original to the model, as well as S2000's, Acura TL's and Honda NSX's. The most popular cars in the H2 class (prior to an important 2007 rules change) were Integra Type R's and Prelude VTEC's, while the H3 class sees mainly Integra GSR's and Prelude non-VTEC's. Look for the Honda CRX Si's and Civics in H4 and CRX non-Si's and Civics with lower horsepower in H5. Note that the examples above are not the only vehicles eligible for the various classes, just some of the most popular. A complete list of eligible vehicles is located within the rules for the series located to the left. 

Since 2007, the H2 class has grown in popularity as a cost-effective class for the masses, one where neither the cost of the equipment nor the expense to maintain the cars serves to exclude participation. Under the new post-2007 H2 regulations, engines are classed rather than the chassis. This allows average Joe racers to run "engine-swap" or hybrid cars against a level playing field. Consequently, scenarios like sticking a B18C5 ITR engine in a 1992 Civic hatchback and competing against a genuine Type-R are perfectly plausible.  The vehicles are equal in weight and have the same allowance for engine prep, chassis, and brake upgrades. With engines like the non-VTEC B20B selling south of $600, the rules changes opens the H2 class to a whole new range of participants who might otherwise be too cash-strapped to play the game.

 One of the reasons for the popularity of the H2 class is the number of people that take their Honda or Acura street car and swap in a more powerful Honda/Acura engine to boost the performance capabilities of their car. This allows the owner, who is usually from a younger demographic, to drive a car with very good performance number, yet still retain the ability to secure affordable car insurance because the vehicle is still classed as a simple Honda or Acura vehicle. Many of those owners begin by taking their car to the track and eventually end up turning them into race cars. With the Honda Challenge H2 class being "the" place to race a vehicle of this nature, it tends to draw them in. While "hybrid" or "swapped" vehicles are eligible to race in both H1 and H2, the main distinction between them is the level of preparation allowed inside the engine. In H1, you're allowed to modify a number of things inside the engine to boost horsepower levels significantly while in H2 these modifications are restricted much further. This allows H2 to be much more cost effective and why we will see it continue to grow in popularity.