Bill Smith
Founder, 1929-2014
Speedy Bill
Since 1952
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Canadian Leaf

Speedway Economy 12 Circuit Wiring Harness

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Main harness is over 12.00" feet in length. Uses spade fuses.
Speedway Economy 12 Circuit Wiring HarnessSpeedway Economy 12 Circuit Wiring HarnessSpeedway Economy 12 Circuit Wiring Harness
Speedway Economy 12 Circuit Wiring Harness

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Q & A

What's in the Box

This harness was designed to offer you all the highest quality components in a package designed for cars with minimum accessories. Each wire is color coded and labeled every few inches.

Our prewired 12 circuit kit will fit all your basic needs and makes wiring a painless process. It is designed especially for the street rod without accessories. It also includes horn relay and connector, turn and hazard signals, dimmer switch connector, circuit breaker for headlights, two flashers, one alternator plug, two ignition switch connectors, plus more.

  • Mainfuse box base is 1-7/8" x 3-11/16"
  • Box height is 3-3/4"
12 Circuit Wiring Harness Installation Instructions (PDF)


  • Kit has two flashers for turn and hazard and they are the 2 prong style
  • 30 amp fuse for heat/cool
  • Two 30 amp relays, one each for the horn and electric cooling fan
  • Horn and electric fan both have 20 amp fuses in dedicated circuits
  • Main harness is over 12’ in length to satisfy most applications
  • Headlights are on a 30 amp fused circuit

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Painless Wiring 10308 18 Circuit Modular Wiring Harness

Designed for those with a T-Bucket or Roadster with minimized needs. This compact, streamlined, simple to install harness has all the basic circuitry needs: headlights, tail lights, brake lights, turn signals, hazards, horn, gauges, wipers, radio, electric fan, electric choke and one accessory circuit. Each wire is color-coded and printed the entire length for ease of installation. As an added plus, the fuse block is modular so if you decide at some point to add additional accessories to your bucket, you can easily snap another four circuits into place. Also included are connectors to GM/Ididit/Flaming River Columns for ignition switch and turn signals and a heavy-duty lead for a high-output alternator.

This wiring harness is just a nice simple basic harness that will work well in a variety of vehicles. It’s for “minimalist” vehicles with no power windows, no power door locks, no power seats... just the basics. Works well in any of the Speedway kit cars.

18 Circuit Modular T-Bucket Wiring Instructions (PDF)

Painless Wiring 10130 14 Circuit Remote Mount Microfuse Wiring Harness

This Painless Micro Fuse Harness solves a dilemma faced by many custom car builders: where to mount the fuse block.  With engine compartments becoming more crowded and underdash space at a premium, there often is not room for a standard size fuse block. The new Micro Fuse Harness is the answer.

The key element is the fuse block itself: it measures just 3" x 3-1/2" x 2" yet holds 12 fuses and 2 relays. You can easily tuck it up under the seat or, because of the unique design of this harness, mount it in the trunk. The fuse block is covered to keep it free from dirt and contaminants.

Wiring harness is designed with three major groups incorporated into it:

  • Engine/Headlight Group Includes: high beam, low beam, park, right turn, left turn, electric fan, horn, starter solenoid, battery feed, alternator (output/exciter wire), coil, water temperature, oil pressure and air conditioning.
  • Dash Group Includes: wires to connect gauges, indicator lights and switches to their proper sources.
  • Rear Light Group Includes: taillights, dome lights, left and right turn signals, brake lights and fuel sender.

The kit includes a 10 gauge alternator wire for use with high amperage (over 65 amps) alternators. All wires are color-coded and printed along their entire length for ease of installation. A comprehensive installation manual with charts and diagrams is included.

14 Circuit Microfuse Wiring Instructions (PDF)

Split Wire Loom Conduit Tubing, 1/4 Inch Diameter, 20 Ft. Long

This plastic split wire loom allows you to clean up that ugly wiring under the hood for a more professional look. This tubing will group and protect your wires from damage.  Simply lay out and insert wires, which will remain inside even with flex.  Choose from 5 colors to customize your engine bay: black, dark blue, purple, red, or yellow. 

  • 20 ft. long
  • 1/4" diameter
  • Plastic split conduit
  • More professional appearance
  • Groups and protects wires against damage 
  • Retains wires under flex and adjustment
  • Comes with zip-ties to secure wire loom
  • Choose: black, dark blue, purple, red, or yellow
Painless Wiring 10202 Universal 28 Circuit / 18 Fuse Chassis Harness

This 28 circuit kit includes most all the power accessory circuits you have been looking to add to your vehicle. The versatility of this harness will allow it to be easily adapted to almost any vehicle. This kit comes without the GM column mounted ignition switch connectors. Included with this harness are the following parts; a GM engineered fuse block & Painless mounting bracket; GM turn signal connectors; prewired plugs for the headlights & dimmer switch; and each wire is custom printed with the circuit identification as well as using GM color codes for easy installation. 

Universal 28 Circuit Wiring Instructions (PDF)

Painless Wiring 21 Circuit Wiring Harness

Easy-to-install 21 Circuit Painless harness features these pre-wired circuits: Coil, emergency flashers, horn, headlights, power windows, wipers, stop lights, gauges, radio (constant hot), air conditioning, heat, electric fan and turn signals. All fuses, flashers and horn relay, pre-installed.

Choose from the Universal Harness or the GM Harness (Chevy) for use with GM column-mounted ignition switch.

21 Circuit Wiring Instructions (PDF)

Speedway Universal 20 Circuit Wiring Harness
                        Whether you're building an option loaded car or just want to have extra circuits available for future updates, this harness is perfect and makes any job painless. Compact 5-1/2"L x 4-1/2"W x 3-1/4"H  fuse block holds 18 standard push-in fuses and can be mounted almost anywhere. 

Each high temperature wire is color coded and labeled every six inches. Also includes GM type steering column connectors. To keep costs down and the quality high, this harness does not include any switches, light sockets or plugs that you would normally already have.

  • Harness has 20 circuits, of which 18 are fused
  • Taillight leads measure 17' long
  • Includes plug for GM column, headlight switch, dimmer switch, and signal flashers

Wiring Harness Installation Instructions (PDF)

Mize Wire Strippers
                        This automatic wire stripper is uniquely designed to hold the wire and strip the insulation without stretching the wire. Just insert the wire, squeeze and release.
Titan Tools 11475 Self Adjusting Wire Stripper
  • Automatically adjusts to strip 24 - 10 AWG wire and cable
  • Crimps 22 -10 AWG insulated and non-insulated wire terminals
  • Crimps 7 - 8mm ignition terminals
  • Wire cutter
  • Comfortable TPR hand grips
Titan Tools 11477 Ratcheting Wire Terminal Crimper
  • Ratcheting mechanism design
  • Adjustable crimping compression
  • Steel jaw
  • Color coded wire sizes
    • Red 22-18AWG-DIN 0.5-1.0mm
    • Blue 16-14AWG-DIN 1.5-2.5mm
    • Yellow 12-10AWG-DIN 4-6mm
Book - How To Wire Your Street Rod
                        By Jack Sweeden. This book is a fully illustrated, instructional guide that takes you step-by-step through wiring your street rod.  12 pages.