Street Legal Aftermarket Parts Guide

When talking about adding aftermarket parts to your vehicle the most important question isn’t what type of exhausts, accessories, modifiable components, cylinder heads, crankshafts, camshafts, chassis parts or turbochargers you should choose but whether or not the modifications that you want to make are actually street legal.

An accessorized look reminiscent of Street Legal Racing Redline may hit the mark with your friends, but it might not play in Peoria. Before you can take your tuned car out in the open you might want to find out whether or not it will earn you a ticket.

Is your Custom Car Street Legal?

The most frustrating thing about street legal aftermarket parts and vehicle customization is the fact that state and local rules vary greatly. On the bright side, the state isn’t allowed to issue any regulations that would impede on federal standards (FMVSS) which set the bar only for vehicle performance, not design. In other words, modifications that do not significantly alter the car’s performance should be accepted in most states.

This doesn’t mean that a state isn’t free to establish its own set of rules that further enforce federal regulations. Besides obvious problems such as leaky exhausts, rust and faulty headlights, there are a few other vehicle customization aspects that may result in your vehicle being legal in one place but illegal in the other. Ideally, you would want to opt for CARB-legal components, but truth be told there are not a whole lot of CARB-approved accessories on the market right now. Therefore, the components that you choose for car tuning should be direct O.E. replacements or be tested by California’s Air Resource Board (CARB).

Vehicle Customization elements that may be legal in a state and illegal in the other:

  • Aftermarket Catalytic Converters installed before January 2009 should be considered legal. However, the emission-check system enforced by the state of California demands aftermarket catalytic converters to be official original equipment (OE) components. If this criterion isn’t met your catalytic converter may not be legal in the Golden State. You can check this by visiting CARB’s official website.
  • Undercarriage Lighting: one of the first things that car enthusiasts add to their tuning list is undercarriage lighting. While some blue nighttime ‘aura’ may sound like an innocent modification it can easily be considered street illegal. As a matter of fact, many states are still arguing over the type of neon lights, LEDs and colors that should be allowed on the street. As a general rule, lights that do not affect rear or front lighting are permitted by the federal government. It would be wise to do some research on color restrictions in various states, as one color may be considered perfectly legal in one, but completely unacceptable in the other.
  • Frame-and-body alterations: another problem could arise from adding too much lift to your car. This is arguably one of the most confusing legal aspects of suspension modifications. While you customize your car keep in mind that many states, like Wyoming, have placed limitations on vehicle height (example: maximum headlight & taillight must be consistent). To avoid this type of situation you should consult with the local DMV. Another aspect to be considered is size of wheels. There are literally no federal regulations regarding this aspect, but modified cars that look suspicious might earn themselves a ticket. The key here would be to ensure that wheels and tires are compatible with the load carrying capacity of your car.
  • High-intensity Discharge Headlamps represent a big no-no in all American states. No matter how perfect, functional and sophisticated your HID headlamps may look; they will never be allowed on the street. The NHTSA (National Highway Traffic Safety Administration) has determined that no HID headlamps can comply with federal regulations.
  • Cold Air Intake Modifications: One of the most inexpensive and effective ways to customize cars is frowned upon by local authorities. Cold-air intakes may boost the power of your engine but they also increase consumption and ultimately lead to more emissions. CARB is keeping tabs on intakes and emissions and an increasing number of states have started following the list as well. Before you add your cold-air intakes make sure that they have passed the CARB inspection.
  • Aftermarket Exhausts: if you want to create your own car, you are probably also considering adding a new exhaust pipe, resonator or muffler. Steve McDonald, vice president for SEMA (Specialty Equipment Market Association) says that there are states, like Massachusetts, which strictly prohibit the use of exhaust-system components that alter sound output. Laws regarding prohibition of aftermarket exhaust-system components are constantly being pushed, and fortunately killed. However, it is only a matter of time until exhaust modifications are banned all-together in favor of stock system components. Most states, including California, use test-station systems that measure decibels.

Street Legal Aftermarket Parts

Below you can find a few examples of aftermarket parts from various producers which are considered street legal. You can consider them during the make of a car, but by no means should you purchase them without consulting with the manufacturer or local DMV.

#1 CompTech – legal in all states

CompTech manufactures top-notch cold air intake systems for Acura and Honda applications. The maximum induction efficiency concept is simple: cold air intake takes place near the vehicle’s front turn signal and is swept through the engine compartment. As a result, the engine can boost horsepower and torque for better performance on the road.

#2 Injen – legal in all states

This company offers a variety of cold-air extensions and induction kits that feature 6061 aluminum construction, CNC milled flanges, specific urethane filters with inbuilt velocity stack and TIG-welded brackets. All Injen products have CARB certification or are awaiting approval.

#3 Vortech Superchargers – legal in all states

Vortech employs the same methods of original manufacturers in order to obtain fully integrated supercharger systems. These systems integrate seamlessly with a car’s existing platform and result in a smooth continuity of power. The vast majority of system can be purchased as tuner kits that override ECM programing and delete fuel system to enable customization of vehicles for better performance.

#4 Russell Performance – legal in all states

Russell Performance’s fuel line kits can be connected to an O.E. fuel filter for increased reliability of tight seal and thread engagement. These products are made from anodized aluminum hose ends and stainless steel braided hoses. The installation process is fairly simple.

#5 AEM – legal in all states

AEM features state-of-the-art EMS (engine management systems) that can be programmed by users and plugged directly into a car’s factory ECU harness. They make viewing, modifying and copying data as simple as clicking a mouse. Owners can predefine templates and configure “quick keys” to be used in the tuning process. The end result leads to better control over engine capabilities, auxiliary devices, ignition timing and amount of fuel delivered.

#6 Skunk2 – legal in all states

Skunk2, available for Honda H22, D16Z and B-series engines, features cam profiles that use computerized modeling techniques for better augmentation of power output. This is achieved with high-tech chill casting technology. The company also supplies customers with upgraded springs directly from Toyota and Honda foundries.

#7 Holley

If you are looking for cat-back systems that offer extraordinary power and mellow performance Holley has what you’re looking for. “The Warlock” features 16-gauge aluminized tubing with a 2-inch mandrel-bend that will smoothen exhaust transition, reduce backpressure towards the muffler, improve quality of sound and increase exhaust velocity.

#8 Apex’i – legal in all states

A’PEX Dunk 115 Series mufflers were designed for 60mm piping & straight-through canisters. These mufflers are constructed from polished SUS 304 stainless steel and feature smooth-flowing pipping treated with titanium particle coating.

As we already mentioned, these are only a few street legal aftermarket parts ideas that will hot wheels aficionados closer to their racing car customization dream while respecting regulations imposed by the federal government. These components are by no means cheap, but who can put a price on vehicle tuning? Other modifiers, that remain on the gray side of legality but are worth considering include steering, interiors, seats and chassis modifications as well as lighting accessories, chrome fitted rims, NOS turbochargers, engine blocks and intake manifolds.

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