Starter wiring can be confusing to someone who has not wired one before, or doesn't understand how they function. The main wiring of an LS starter only requires 3 connections:
- Main Power Connection: The main power connection on most LS starters is a large hex stud, typically a 13mm nut. Ls starters can pulls hundreds of amps of current so using a sufficient wire size is CRITICAL. This is a place when bigger is better and nothing smaller than a 2 gauge wire should be used. On an e9x swap this wire will run up to the strut tower large post. Be sure not to connect it to the smaller post as it is not fused sufficiently. The main power connector is shown below circles in red. Please note there are two similar studs. DO NOT CONNECTO THE MAIN POWER TO THE STUD THAT HAS THE CABLE GOING TO THE STARTER MOTOR. Doing so will just run the starter motor constantly.
- Solenoid Connection: The solenoid connection on an ls starter can be one of 2 different style connections. One is a 8mm hex nut, and one is a round single pin connection. Depending on the year and style starter you use you may have either one of these. We like to use 2007 style truck starters which are the short body with the 8mm hex stud. This connection will typically be run to the DME box with a 10ga wire to the location on the starter shown below highlighted in yellow. If you are using the plug type, the connector is available here https://amzn.to/3BOsjKY
- Ground Connection: The ground connection to the starter is run through the block mounting surface of the starter, shown in the photo below highlighted in blue. This is the ground connection of the starter motor and carries the same current as the main power wire. This connection should be clean, bright non painted metal on both the starter and block. The block then should have a ground wire from a clean, bright non painted boss to the body. The ground connection should be a wire capable of carrying the same current as the starter (2g or larger)