Slot car racing (also called slotcar racing or slot racing) is the competitive hobby of racing with powered miniature autos (or other vehicles) which are guided by grooves or slots in the track on which they run.
Slot cars are usually models of actual automobiles, though some have bodies purpose-designed for miniature racing. Most enthusiasts use commercially-available slot cars (often modified for better performance), others motorize static models, and some "scratch-build," creating their own mechanisms and bodies from basic parts and materials.
Slot car racing ranges from casual get-togethers at home tracks, using whatever cars the host makes available, to very serious competitions in which contestants painstakingly build or modify their own cars for maximum performance and compete in a series of races culminating in a national championship. Some hobbyists, much as in model railroading, build elaborate tracks, sculpted to have the appearance of a real-life racecourse, including miniature buildings, trees and people, while the more serious competitive racers often prefer a track unobstructed by scenery.
"Digital" racing is slowly building up popularity. This allows more than one car to run in the same slot as each car is controlled by digital signals sent to it. With the Slot.it oXigen digital system, up to 20 cars can be operated independently on a two lane track. In digital slot racing the driver also has a button on his controller to activate a lane changer which allows their car to switch lanes and therefore is able to overtake and also offers the selection of a racing line through a given corner.
In 1:32 and HO scales, traction magnets are often used to provide downforce to help hold the car to the track at higher speeds, though some enthusiasts believe magnet-free racing provides greater challenge and enjoyment and allows the back of the car to slide or "drift" outward for visual realism.
- 1:24 scale cars are the largest slot cars commonly raced. A typical 1:24 car might be 7 to 8 inches long (18-20 cm). 1:24 cars require a course so relatively large as to be impractical for many home enthusiasts, so most serious 1:24 racing is done at commercial or club tracks.
- 1:32 scale cars are smaller and more suited to home-sized race courses but they are also widely raced on commercial tracks, in hobby shops or in clubs. A 1:32 car averages 5 to 6 inches (13-15 cm).
- HO-sized cars vary in scale, running from 1:87 (generally the older cars) to 1:64 in scale; but they all run on track of approximately the same width, and are generically referred to as HO slot cars. A typical car is from 2.5 to 3.5 inches (5.5-8 cm). Though there is HO racing on commercial and shop-tracks, probably most HO racing occurs on home racetracks.
In addition to the major scales, 1:43 slot car sets are generally marketed today (2006) as children's toys. So far, there is little organized competition in 1:43, but the scale is gaining some acceptance among adult hobbyists for its affordability and moderate space requirements. An average car would be 4.3" (10.9 cm).
Shop and club tracks used for serious competition (especially in 1:32 and 1:24 scales) are usually hand built "Routed Tracks" in which the guide slots for the entire racecourse are cut into one or a few large pieces of sheet material (such as plywood or MDF) providing a smooth and consistent surface that allows cars to perform to their full potential.
Competition tracks are usually laid out as road courses with many turns, though ovals and "tank tread" (trapezoidal) ovals are also fairly common. On a road course or oval, each car and each lane is generally marked with "lane tape" of a distinguishing color, allowing the corner marshals (officials) to return cars that have spun off the track to the proper lane.
Generally, tracks for formal competition may have banked corners and may bridge one section over another, but may not otherwise use "trick" configurations. Home tracks often include special features to increase the drama and/or challenge of racing, such as slots that wiggle or squeeze the lanes together, bumps, airborne jumps, or uneven surfaces, but these are typically called "toy" tracks and are not used for competition in more serious organizations.
A different segment of the hobby is slot car drag racing on a long straight strip of track. In HO size, these dragstrips are often a scale quarter-mile.
1:24 Scale tracks used for competition are generally 6-8 lane routed tracks with either wooden or flexible plastic retaining walls. The tracks are usually located in commercial or purpose-built racing centres. Most of the tracks used in the USRA regional and national events are either original American Raceways (AMF) commercial tracks or variations of these designs made from original blueprints. Generally tracks used for regional or national competition have an epoxy or polymer painted surface with recessed braided electrical contacts. In USRA Division 1, the use of traction-enhancing compounds on the racing surface ("glue" or "goop") may be applied to the racing surface by the competitors.
The most famous type of 1:24 commercial track is the "Blue King" (155 foot lap length) which is the track that is recognized for world records in 1:24 racing. The current (2006) world record qualifying lap is held by Benny Justice at 1.4632 seconds, which computes to 105.93 feet per second! The "King" track segments are "named" starting from the main straight in an anti-clock wise direction: bank, chute, deadman (corner), finger, back straight, 90 (corner), donut (corner), lead-on, and top-turn. Generally the "King" tracks are used for wing-car racing, where un-banked "flat" tracks of various designs are used for scale racing. A prime example of a championship "flat" track is the Gary Gerding designed track installed in July 2007 at Mid-America Raceway and Hobbies near Aurora, IL (the site of the 2009 USRA Division 2 National Championships).
1:32 Scale competition is generally run on the same routed tracks as 1:24, at least in the USA.
HO Scale competition tracks are typically between 60 and 100 ft in length and 4 to 6 lanes wide. Plastic tracks, often modified for improved performance, are more common in HO competition than in the larger scales, as is the use of large home courses for formal racing.
Many tracks use banks of lead-acid batteries to produce sufficient high amp DC power, but in recent years, relatively inexpensive high-quality electronically-regulated power supplies have become more popular to achieve consistent and clean power.
The second (and most common) way to run a round robin is to have four drivers (or as many as there are lanes) start at a time, and rotate through all the lanes, before being replaced by the next set of drivers. This is known as a "heat" or "consi". Often a small amount of practice time (usually 30 seconds) will be given to the drivers prior to the start of each heat. If there are an odd number of drivers such that they are not wholly divisible into the number of lanes, one of two measures is taken: either a heat is run with one or more positions unfilled, or a heat is run with extra drivers, with a "sit-out" position. After all drivers have run their heat, placement is determined by total laps completed.
Often round robins are modified to include a "main" and sometimes also a "last-chance" heat. When run with a main, the round robin is run as normal, but at the end the top competitors (as many as there are lanes) run an extra heat. This heat is usually longer (3 to 5 minutes per segment, 1.5 "pit" time, and 1 minute practice before the heat). At the end the drivers are re-placed based on the new lap totals.
Last-chance heats are similar to mains. The top competitors (number of lanes minus one) from the round robin move into the main, and the runners-up (as many as there are lanes) are moved into the last chance heat. The last chance heat is run before the main, and is usually run with the same time parameters as the other heats. At the end, the top competitors from the last-chance are re-placed based on their new lap totals (though never lower than a comptetitor that didn't make the last-chance), and the winner of the heat moves into the final position in the main.
Bracketed formats are usually reserved for national events, and include qualifying, elimination consis, semifinals, and a main.
When the segment time has elapsed, a small amount of time, usually one minute, is given for the driver to switch lanes, perform any necessary maintenance to his car, and return his car to its resting position (albeit in a different lane). At the same time, the next driver in the succession moves into the first lane, placing his car at the starting position. When a driver completes all the lanes, his total laps and final position are recorded. This continues until all drivers have completed all lanes. Lap totals are compared to determine placement.
Most racing organisations allow a "track call" (where the power is turned off) for a situation where a race car is in the wrong lane. This is also referred to as a "rider" and is considered to be a dangerous and unfair situation. Track calls are also sometimes used in the event that a car flies off the table and cannot be located by a marshal.
1:32 scale racing organizations In 2004, the True Scale Racing Federation (TSRF) was established by former pro 1:24 racer Phillipe de Lespinay (aka: PdL) with the goal being to establish a North American "true scale" 1:24 and 1:32 North American racing series. The TSRF concept is very similar to full-scale "spec" racing where only TSRF approved equipment can be used for competition.
HO Organizations There are two large HO racing organizations in the US: HOPRA (the HO Professional Racing Association) and UFHORA (the United Federation of HO Racers Association). Each hosts a national competition annually, usually in July. There are many state-wide organizations running under HOPRA and/or UFHORA rule sets.
"The Fray In Ferndale", California boasts the largest turnout of any slot car race in the world. The highly competitive race is held yearly, in February, and more than 100 individuals, and 16 teams, show up to race on 8 tables. This is the race that determines the direction that the hobby takes, regarding the venerable Aurora Thunderjet. The race has been held since 1997.
Unlike 1:24 scale tracks, HO race tracks can be small enough to fit in common basements. Therefore, most state organizations run some, if not most, of their series on home tracks as opposed to hobby shop tracks. Additionally, home tracks are often used for national competition.
HO Scale Oval racing is very popular in the Northeastern USA. The cars are molded to look like Dirt Modifieds and Sprint Cars. The Sprint Cars and Dirt Modified cars are raced on oval tracks anywhere from 8 lanes to 4 lanes.
USRA Division 1:
a) Spec-15: Amateur only b) GP-12: Amateur and Expert c) International 15 (15A): Amateur and Expert d) Cobalt 12/15: Amateur and Expert e) Group 27: Amateur and Expert f) Group 7 (open): Semi-Pro and Pro There is also a class in its genesis called "One Motor Only" that is similar to Group 7 with the difference being that motor changes after tech are not allowed.
USRA Division 2:
a) Group 10 Stock Car b) Production 4 1/2" Stock Car c) GTP d) GT-1 e) GT-12 f) C-12e g) Eurosport
USRA Division 3: (Proposed)
a) Nostalgia Can-Am b) Vintage NASCAR c) Nostalgia F1 d) TSR e) Vintage "Thingie"
Note- in spite of the USRA not yet recognizing "Division 3", independent sanctioning bodies on the east and west coast have been organizing and hosting Nostalgia Can-Am and Nostalgia F1 races. Interest has been growing in a "spec" Can Am class which is expected to begin having major events in 2009.
See the current edition of the USRA rules for technical specifications and approved parts for USRA "group" racing classes.
Formula-2000 F-2000 is raced primarily in the midwest; it is a variation of the USRA Division 1 rules with the prime exception being traction/braking "glue" is not allowed to be applied to the racing surface by participants. Motor changes once the race has started are not allowed, and there are other rules restrictions intended to reduce the cost of participation.
Other international organisations such as the IMCA and ISRA have their own classifications and technical regulations. Contact the organisation directly for their latest rules and series schedule.
HO Racing Classes
HOPRA and UFHORA run similar classes and similar rules for those classes. The following are brief explanations of some of those classes.
General rules specify the size of the car and anything else that pertains to all classes.
Superstock (HOPRA and UFHORA): Cars may have at most 4 magnets (2 to drive the motor and 2 "traction" magnets for additional downforce). All magnets must be ceramic. Motors must be stock, and may be balanced and/or trued (referred to as "hot-stock").
Modified (HOPRA): Also known as "ceramic modified" is the same as superstock above, but the motor is unrestricted and the chassis may be sanded.
Modified (UFHORA): Cars may have at most 4 magnets (2 to drive the motor and 2 "traction" magnets for additional downforce). Motor magnets must be ceramic, traction magnets may be polymer. Motor must have a resistance of no less than 3.0 Ω on each pole.
Polymer Modified (HOPRA)/Restricted Open (UFHORA): Cars may have at most 4 magnets (2 to drive the motor and 2 "traction" magnets for additional downforce). All magents may be polymer. Motor is unrestricted. Chassis may be sanded. Shunt wires may be used.
Unlimited (UFHORA and HOPRA): No restrictions. Custom chassis permitted. Six neodymium magnets are usually employed.
Am Spec-15: Luka Bernadino (Brazil) Am Box-12: Alan Sulak (Texas) Expert Box-12: Mike "Erkle" Tylinski (NY) Am International 15: Kevan Taylor (Virginia) Expert International 15: Mike "Erkle" Tylinsky (NY) Am Cobalt-12: John Davis Jr. (Mid Atlantic) Expert Cobalt-12: Connie Aloise (California) One Motor Opens: Joe "Chubbie" Salzman (NY) Geezer Group 7: Richard Curnutte (California) Am Gp 27: Mike Iga (Chicago) Expert Gp 27: William Skinner (NY) Semi-Pro Group 7: Shelby Thomas (Texas) Pro Group 7: Joe "Chubbie" Salzman (NY)
The 2006 Division 2 (Scale) Nationals were held at Slot Car Raceway in Rohnert Park, CA starting on April 18 and concluding on April 23rd. 2006 Scale Nats Champions:
1:32 Eurosport - Paul Gawronski
AM GT-12 - Zac Grinstead
Expert GT-12 - Herman James
C-12 Eurosport - Paul Gawronski
Am GTP - Chris Rodriguez, Jr.
Expert GTP - Duran Trujillo
Am GT1 - Ron Southern
Expert GT1 - Paul Gawronski
Jr Group 10 NASCAR - Zac Grinstead Am Group 10 NASCAR - Zac Grinstead
Expert 4.5 NASCAR - Duran Trujillo
Expert Group 10 NASCAR - Duran Trujillo Am 4.5 NASCAR - Bill Vanderziel
The President of the USRA, Chris Radisich, is considering sanctioning a "Division 3" which will be for vintage-type or retro slot racing cars. The rules and Division 3 series are at this moment still evolving, but the purpose is to create a class where the cars raced are easily recognized and to shift away from expensive high tech componentry.
The 25th World Slot Car Championship (aka "The Worlds") was held May 17-21 2006 in Rio De Janeiro, Brazil at Top Slot Raceways. It was sanctioned by the NPRA which is a South American slot racing federation.
2006 Worlds Champions: Group 7 (open) - Joao Carlos Geraldo