- Mini sprint
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Mini sprint cars racing at Angell Park Speedway
A mini sprint is a type of open wheel racing vehicle. Mini sprint cars resemble the shape of a full-size sprint car and the size of a midget car. Although often used liberally to describe several different types of motorcycle powered open wheel racing cars, the term mini sprint actually applies to cars that have an upright style chassis (the driver sits upright in the seat as in a sprint or midget), a center mounted 4 cylinder motorcycle engine and dimensions and appearance that are similar to today’s midget. Mini sprints are chain driven and use 13 inches (33 cm) wheels and tires.
Contents
The car
An example of a mini sprintThe mini-sprint shares overall dimensions that are similar if not identical to a full-size midget. Mini-sprints have a wheelbase that is between 66 inches (1,700 mm) and 74 inches (1,900 mm). In fact many competitors are actually making use of old midget chassis. Mini-sprints are exclusively front engined cars that have their engines located near the middle of the chassis. The maximum offset from the centerline of the chassis is 6 inches (150 mm). (this is opposed to modified midgets or super-lites that have their engine located radically offset to the left). Mini-sprints also share suspensions that are identical to sprints and midgets. The most popular chassis is the four bar. This is a suspension system that makes use of 4 torsion bars (2 front / 2 rear) that utilize torsion arms and shocks to regulate suspension travel.
However, there are a growing number of cars that utilize a torsion bar rear set-up with a coil-over front set-up. This means the rear of the car utilizes a torsion bar system that is identical to the 4 bar set-up, while the front-end uses shocks with coil springs. Mini-sprints utilize a solid, live rear axle that is positioned in the chassis by a Jacobs Ladder or panard bar. Unlike the midget or the sprint car, the final drive on a mini-sprint is a roller chain. This is one of the keys to keeping the cost of this form of racing down. A chain drive system might cost around $300, whereas a quick change rear end like those used on sprints and midgets cost upwards of $2,000. Gearing on a mini-sprint is determined by changing either the front or rear sprocket or a combination of both. Mini-sprints make use of 13 inch wheels and tires that are identical to those found on midgets. Most mini-sprints make use of a steering box, however a few manufacturers are utilizing steering racks. Mini-sprints carry their fuel in the rear of the car in tanks that vary from 5 to 19 US gallons. They have roll cages that are constructed of at least 11/4”, .095 wall Chromoly tubing. Many organizations are now requiring thicker tubing.
Sanctioning bodies
United States
- Florida Mini Sprint Association
- Granite State Mini Sprints Race Club
- Midwest Mini Sprint Association
- Northeast Mini Sprints
- Rocky Mountain Mini Sprint Association
References
Categories:- Auto racing by type
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