Street Drag Racer/Hot Rod

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Drag Racer (Production-Based)

Production cars have likely been drag raced since there were two or more available. However, the first notable racing took place in the 1930s when dry lake beds in southern California provided drag strips. They have enjoyed continued growth due to the low entry costs for beginners and the aftermarket customizability of production machines for drag racing.

Production-based drag racers are characterized as a production vehicle modified with various degrees of customization in order to drive as quickly as possible in a straight line over a fixed distance. No other type of race car, except perhaps Formula One is capable of generating as much acceleration as the drag racer. As the classes progress, bigger horsepower and bigger driving tires appear, alongside more safety and traction aids.

Any car configuration can be dragged raced—Front, mid or rear engine with front, rear or 4 wheel drive. The predominant configuration is front engine/rear wheel drive, but with many modern cars being drag raced, front and four-wheel drives have become more popular.

Racing is held on local drag strips in almost every part of the world.

Power and Weight Stats
Horsepower (Typical Range) 125-800
Race Weight (Typical Range) 1135-1589 kg
2500-3500 lb

Design and Construction

Race Car Models of This Type

Almost any production race car, although many builders will start with a muscle or sports car. NHRA classes include Comp, Super Stock, Stock, Super Gas, Super Street, Top Sportsman, Pro Mod

Build Your Own Production-Based Drag Racer

Knowledge Level

At the entry-level of production-based drag racers, you will find working knowledge in handling, chassis, suspension, powertrain, aerodynamic and safety useful. More advanced knowledge in these six major areas of the car design may help you optimize the traction and performance within the regulations of the class chosen and do so with a lower budget than others.

Key areas of knowledge as you progress would include suspension and powertrain. Both areas directly affect how the power is generated, how it is transferred to the tires, and how the car's weight distribution is used to generate traction and acceleration.

Design Challenges

Weight Distribution: Weight transfer to the driving tires upon launch is critical in drag racing. The greater the weight transferred the better. However, the front tires must continue to provide steering capability. For front-wheel drive vehicles the goal is to minimize weight transfer away from the front tires.

Suspension: Suspension, within the rules should permit maximum weight transfer to the driving tires and remain compliant to the road surface. On vehicles with leaf-springs, traction bars are a useful add-on as the help prevent wind-up of the springs, and damage to U-joints. On other types of suspensions, minimizing or eliminating tire hop/chatter when launching is vital, as the second the tire leaves the road, the forward acceleration stops. On front wheel drive cars, minimizing rearward weight transfer (Squatting) with stiffer rear springs will produce better acceleration. In all cases, the widest tread width/largest diameter tire will give the best acceleration where the rubber compound is the same.

Chassis: Depending on the class it may be possible to reduce weight by removing interior components and by replacing stock body panels with lighter composite panels.

Powertrain: Depending on the drive configuration and class regulations, there are modifications that can be made to the powertrain to increase power, maximize its delivery to the tires, and optimize weight distribution.

Increasing power: Forced induction (Super/turbochargers), freer flowing intake/exhaust, removal of parasitic accessories (ie. air conditioning).

Gearing: Gearing for the engines power band will use the power the engine produces in the most efficient way.

Limited slip differentials: Putting power down to both wheels to aid traction

Drivetrain weight distribution: Moving heavy items like batteries toward the rear of a rear wheel drive vehicle will aid traction. Moving them farther forward on a front-wheel drive vehicle will aid traction.

Aerodynamic: In classes where aerodynamic modifications can be made (i.e. Wings/spoilers added for traction purposes, body drag reduction), there may be merit to making these changes. However, the speeds required to produce sufficient downforce and the drag generated by the aero devices must be evaluated to ensure there is a real increase in performance.

Safety: Providing a substantial crash/rollover safety cell for the driver is usually a requirement where speeds and risk exceed the limits of a production car's structure. A racing seat and racing harness are also usually mandatory at that point. If a vehicle is to be upgraded further for drag racing use, a roll structure, racing seat and racing harness should be a first priority as it provides confidence to the driver as well. Consideration in higher power classes should be given to fuel safety cells and fire protection.

If you intend to race under a sanctioning body, always read and understand the regulations of your chosen racing class before designing or building any race vehicle.

Design Resources

Learn the basics about race cars and race car design from our free online knowledge series

Download our free race car design aids to assist you designing your race vehicle.

In-depth books and learning resources we recommend for production-based drag racer design.

Join our forum to ask and find answers to your production-based drag racer design/construction questions.

Construction Challenges

Having sufficient space for making modifications and fabricating custom components is important, as a cramped workshop can be difficult to work in.

Depending on the level of customization from stock production, the tool selection required to modify and maintain the car will grow.

Many customized components can be farmed out to speed shops or fabrication shops, but if you are interested in learning the skills yourself, the same money can be spent on equipment and teaching yourself.

Build Costs

For entry-level drag racing with a stock or near-stock vehicle the costs will be very low. As you progress to higher and higher performance, the costs will be incremental, which spreads the overall cost of your investment over a larger period of time.

For production-based drag racers there is a whole industry of speed part manufacturers, so many components can be purchased off-the-shelf. These parts reduce the cost of the overall machine when compared to fabricating your own, but as in almost all racing circles, any part labeled with "racing" will cost more.

Build Effort

The effort required to build a mid to top-level production-based drag racer from a stock production car is considerable, but can be spread out over many years of racing. The lessons learned along the way and the experience gained will help with each new upgrade.

Racing Cost

At the entry-level, consumable costs low—Tires probably form the single largest consumable expense. As power and speeds rise, tire costs and engine rebuilds tend to become more frequent. Depending on your mechanical skills or willingness to learn, the cost of rebuilding an engine can be limited to parts if you do it yourself.

Transportation and Support Equipment

At the entry-level, stock production vehicles can be driven to the drag strip. However, as a car becomes more customized for racing and less streetable, trailering becomes a requirement.

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