American Autocross

American autocross is a form of motorsport where drivers individually compete to set the fastest time on a temporary course.

American autocross events are usually held in large paved areas like parking lots or airfields. Typically, new courses are created for each event, so drivers must learn a new course each time they compete. Courses are designated by a series of traffic cones set out to create "turns" drivers must navigate. Prior to driving, each competitor walks the course, takes mental notes and develops a strategy to be refined upon subsequent runs. National organizations such as the Sports Car Club of America (SCCA)^[1] and National Auto Sport Association (NASA) sponsor autocross events throughout the United States, and many areas have independent autocross clubs. Automobile manufacturers and their associated clubs (e.g. the BMW Car Club of America) sometimes hold marque autocross events, although many of these events are open to any car owner provided they first join the club. Each local club has its own membership rules.

Participation

One of the primary attractions of autocross is that it is an inexpensive way to get involved in motorsports. The potential for car damage is low because of autocross' low average speeds, lack of physical obstacles, and lack of wheel-to-wheel racing. For this reason, most autocross participants compete in "daily drivers", which is not the case in most other forms of motorsport. Many clubs further reduce the barriers to entry by including classes and instruction specifically for novice drivers. A helmet is required, but most hosting organizations offer loaners for novice attendees.

The SCCA has ladies' classes for autocross which share the same rules as the open classes but limit participation to women. It is common for husbands and wives, boyfriends and girlfriends, brothers and sisters or even two unrelated drivers to share the same car but run it in their car's open class and its corresponding ladies' class. Women are permitted to run in the open classes if they desire and many do quite successfully.^[2]

Autocross for novices

Many local autocross events last an entire day and may include up to 100 drivers. Many events encourage or require participants to "work the course" as a corner worker. This entails repositioning cones that drivers have hit, as well as other specialized jobs that help the event run smoothly. In larger events, a driver may be allowed to drive the course for eight to ten "runs" against the clock. Each run typically lasts between 30 and 90 seconds depending on the course length, giving a driver about ten minutes of total driving time for a whole day of work. Navigating a course quickly takes time and many novice drivers do not post fast times until after their first year. Many clubs insist that new drivers get the help of an instructor to aid them as they navigate. It is common for beginners to get lost in the sea of cones their first time through a course. An instructor can visually point out where the driver should go so that they may focus on driving the car.^[3]

Cars and classing

Classes and rules vary by sanctioning bodies, but most competitors run lightly modified or unmodified (stock) vehicles. SCCA classing, which is also adopted by many independent clubs, has a variety of Street (formerly known as Stock) classes which range from Super Street for cars like the Corvette Z06 (either the C5 or C6 variants) and Lotus Elise, to H Street for Honda Civics and Mini Coopers. The Street classes allow very little change from how the car was originally manufactured; most items that can be changed are the normal wear items (filters, street-legal tires, shocks/struts, ignition wires). Just beyond Street, there are Street Touring and Street Prepared classes which allow mild modifications, such as those to suspension (wheels, springs, shocks), external engine parts (intakes and exhaust manifolds), and interior (replacement of seats, not removal).

At the other end of the spectrum, the most significantly altered production vehicles that are mostly still street legal are the Street Modified cars, which retain production-based bodies and motors but little else that is stock. Street Modified cars often produce in excess of 350 WHP, can reach 60 mph from a standing start in less than 3.4 seconds, and can corner in excess of 1.7 transient lateral Gs. Prepared class is for production-based full-on race cars with stripped interiors, major suspension changes, heavily modified motors, and true racing slick tires. Typically, Prepared class cars are typically no longer legal for street use and are consequently brought to events on trailers. The SCCA D- and E-Modified classes also have production car backgrounds, but extend the Street Modified and Prepared allowances to silhouette level, allowing any automotive-based engine, total suspension redesign, and complete replacement of the body (typically with lightweight alloys or composites) as long as the general shape of the original car is still recognizable.

There are usually classes for purpose-built race cars imported from other series (including Formula Fords, Formula Atlantics, Formula 500s and vehicles similar to American oval-track stock cars) but most autocross cars are based on production cars.

The fastest autocross cars are purpose-built "specials" (A Modified in SCCA Solo) with small lightweight bodies, sticky tires, wild wings, powerful engines, and short gears. While their top speeds are typically limited by gearing, their transient cornering capabilities far exceed those of vehicles not expressly designed for autocross use. ^[4]

Related motorsports

The sport described above is commonly known as autocross or "Solo" (the SCCA's brand name for it) in the United States. Other regions of the world refer to it differently. Parts of Canada and Eastern Europe (Russia, Ukraine, Moldova for example), call it autoslalom. In the United Kingdom, autocross is known as auto solo. There, autocross refers to a similar sport that is held on unpaved surfaces like grass and dirt (see SCCA RallyCross). In Southeast Asia, countries like Malaysia and Thailand refer to the sport as autokhana.

Motorkhana (as it is known in Australia and New Zealand) and autotesting (UK and Ireland) are related sports. With speeds rarely exceeding 40 mph (60 km/h), both motorkhana and autotesting are slower than American autocross, require hand-braking, and have sections that must be navigated in reverse. Alternately, autocross speeds can exceed 60 mph (100 km/h) and courses requiring drivers to reverse are generally prohibited. Hand-braking is also uncommon and not usually necessary on a typical autocross course.

These are similar to the Japanese gymkhana, another type of handling competition. Gymkhanas are even tighter than motorkhanas and autotests, with numerous 360-degree turns around cones and courses that loop back upon themselves. Fast times require a lot of sliding and the end result ends up looking similar to a cross between autocross and drifting. Gymkhana does not usually require entering reverse gear.

In ProSolo, an SCCA-sanctioned variant of autocross, two cars run side-by side on mirror-image courses after starting at a "Christmas tree" starting system similar to that used in drag racing. ^[5]

Further reading

• Watts, Henry (January 1990). Secrets of Solo Racing: Expert Techniques for Autocrossing and Time Trials. Loki Pub. Co. ISBN 0-9620573-1-2.
• Turner, Richard (1977). Winning autocross solo II competition: The art and the science. National Academy for Police Driving. ISBN 0-932522-01-7.
• Pagel, Jim (1972). How to win at slalom & autocross. ISBN 0-87112-053-4.

References

External links

• Introduction to autocross by the SCCA