Help is just a click away!
Click here to chat with a Speedway Team Member
💬
Online - Chat with us!
Chat
Products to Compare (max of 3)
X
Compare These Parts
Talk to the Experts. Call 800.979.0122, 7am-10pm, everyday.
Customer Service
Since 1952
in
in
Talk to the Experts. Call 800.979.0122
Shop By
Support
Account
Street Race Truck More... The Toolbox

GM Alternator Buying Guide

7/1/2016
Tags: Tech

Whether you’re looking for a simple aftermarket replacement or a heavy-duty performance alternator, Speedway Motors offers three main types of alternators that GM originally designed. The 1-wire, which is great choice for a clean setup and easy installation, the 3-wire OEM-style replacement, or the earliest style externally regulated alternator.

1-Wire

A 1-wire alternator offers a simplified installation and clean setup. It has one wire that connects the charge terminal directly to the battery or a 12V source. They are internally regulated and grounded through the block. 1-wire alternators will not have a way to hook up a warning light, but most custom applications work well with a voltage gauge in its place. The cut in speed (the speed at which the regulator begins to charge) will be slightly higher (1200rpm or higher) than most alternators which means they do not charge at idle. One exception to this is Tuff Stuff's 140amp performance 1-wire alternator, rated to charge 80amps at 750rpm.

3-Wire

A 3-wire or “OEM-style” alternator will also be internally regulated and have a charge post and two terminals on the side (viewed from the back.) Typically the left terminal is for the field or exciter circuit and the right terminal is used for the sensing circuit. They are slightly more complicated to wire up but have the advantage of charging at lower rpm and the ability to use an original warning light.

Externally Regulated

These older style alternators can be referred to as a 2-wire, 3-wire, or even 4-wire. Regardless of the name, the important difference is that they are designed to work with an external regulator. They were used after generators were phased out from the mid 60’s until about 1972. They can be identified by two vertical terminals where the connector plugs in.

Products Featured in this Article

Related Articles

Air Fuel Ratio Tuning on a Sprint Car Engine
by Dalton Johnson - Posted in Tech
5/15/2019
Learn what goes into setting the fuel for your engine and how to change the density altitude, ADR, main pill and high speed pressure to optimize a/f ratio.
Wrapping a Car
by Caleb Filipi - Posted in Tech
5/13/2019
How to vinyl wrap a car. Use our guide on using a heat gun tool on your race car. Learn how to remove creases from the vinyl and the best temperature setting to use for installation.
How to Build 4-Link Bars
by Speedway Tech Team - Posted in Tech
5/9/2019
Do you have a project that will require you to build your own 4-link bars? Here's a demonstration on how to determine the bar length, weld the parts and assemble the links using steel tube ends weld bungs and forged 4-bar rod ends.
Upgrading Your Air Cleaner Assembly
5/9/2019
Learn the proper steps in upgrading your air cleaner assembly to ensure clean air, allowing your engine to more easily make the power that it should.
Take a Kid to a Car Show
by Jeff Karls - Posted in Street Rod
5/7/2019
What is it like growing up going to car shows? This story explains how attending car shows is a way of life and how the tradition is passed on from generation to generation.
Tech Talk: Roll Cage Tube Joint Tubing Notcher
5/6/2019
In this video, Joe and Darrian discuss and demonstrate how to properly set up and use the Speedway Tubing Notcher. It’s the perfect tool for fabricators and hobbyists alike! Use it to make headers, custom chassis, roll cages, or anything in between.
Ignition Upgrades for Classic Mopar Muscle
by Tyler Wesely - Posted in Street Rod
5/1/2019
Bringing an old Mopar back to life isn't always a breeze. Fortunately, MSD has come up with a solution for those outdated and unreliable points-type ignition systems. Find out how to install a MSD 8386 distributor and MSD 5531 spark plug wires
Don't Miss It
by McKenna Haase - Posted in Tech
4/23/2019
As we kick off the racing season, remember that attitude is everything. One of the best ways to preserve a positive attitude at the track is to have realistic expectations on both ends of the spectrum.
Sprint Car Tire Tech and Maintenance
by Dalton Johnson - Posted in Tech
4/23/2019
Learn some of the tips and tricks when it comes to racing tires. These tips will help you not only get your power down into the racetrack, but some may also help your tires last longer.
Project Chevelle: 383 vs. LS Shootout Tech Article
by Joe McCollough - Posted in Tech
4/17/2019
Since LS swapping our Chevelle, there's been a lot of debate going on about which was better; the traditional 383 or the Gen III LQ9. Well, which one really gave us the most bang for the buck? Read on to find out...
Suggestions
Error
X
Note
X
Ok