1. Tuner Category - Electrical

In addition to everything allowed in Sport Category like spark plugs, spark plug wires and grounding cables, Tuner Category allows you to replace your battery—even to a lightweight one—and relocate it if you want. Of course, this doesn't apply to electric or hybrid cars, because we're pretty sure that would get out of hand! You can also replace the alternator and install things like electric fans.

Read the full rules to see details on things like cables and making sure it's all done safe.

Except for those with electric and hybrid powertrains, Tuner Category vehicles may do everything allowed in Sport Category plus the list below.

1. OE traction control systems may be electrically disabled, but not removed or altered in any other way.

2. The make, model number and size of the battery may be changed, but not its voltage.

3. Relocation of the battery or batteries is permitted but not into the passenger compartment. If the battery is relocated and the original battery tray can be removed by simply unbolting it, the tray may be removed or relocated with the battery. Holes may be drilled for mounting or passage of cables. Longer or shorter cables may be substituted to permit relocation.

4. The number of battery or batteries may not be changed from standard. The area behind the rearmost seat is not considered to be within the passenger compartment. The area under the rearmost seat is within the passenger compartment.

5. Holes may be drilled in the firewall to permit passage of electrical wiring. It should be no larger than necessary to facilitate allowed modifications in this section and shall serve no other purpose.

6. Any starter, generator or alternator may be used in the original position. An alternator or generator must have an electrical output (including amperage) equal to or greater than the original equipment unit. Any generator or alternator pulley and belt of the same type as standard may be used.

7. Electrically driven fans are allowed. Flex fans are not allowed.

1. The make of spark plugs, points, ignition coil and high-tension wires is unrestricted including spark plug wires having an in-line capacitor. Substitution or addition of ignition coil mounting brackets is permitted, provided they affix to the original standard location and serve no other purpose. (Modification of the distributor cap for the purpose of installing allowed non-standard components is not permitted.)

2. On cars made prior to January 1, 1968, any ignition system using a standard distributor without modification may be used.

3. Ignition settings may not be mechanically adjusted outside factory specifications.

4. Additional battery hold-down hardware may be added to supplement the standard equipment in order to meet safety inspection requirements. It may serve no other purpose.

5. Tire pressure monitoring systems (TPMS) may be disabled. Altering the signal to the TPMS is permitted.

6. On cars without the ability to turn off anti-lock braking systems (ABS), electronic stability control and/or traction control (ESC/TC) from the manufacturer, modifications to defeat the ABS/ESC/TC are permitted. These modifications are limited to altering the inputs to the ABS/ESC/TC processor (e.g., removing fuses, unplugging yaw or steering angle sensors, altering signals, etc.) and may serve no other purpose. Any codes or error lights resulting from ABS/ESC/TC modifications are permitted.

7. On cars equipped with computer-aided gear selection or “skip-shift” features from the manufacturer, modifications to defeat the skip-shift feature are permitted any may serve no other purpose.

8. On cars with electronically-controlled exhaust pipe valving downstream of the catalytic converter, devices may be added to satisfy the PCM/ECU provided the OE component is still installed. Such devices shall perform no other function.

9. The addition of electrical grounding cables and associated distribution blocks/terminals is permitted. Holes may be drilled for mounting only. This does not permit the use of electrical enhancement components such as condensers, voltage controllers, etc.