When you build your next small-block or big-block GM motor, have you considered using a serpentine system? Not only does it look cool, but it has a few massive benefits as well. These include eliminating all those extra belts and gaining up to 10% more horsepower. However, before taking the leap into a serpentine system, there are a few prerequisites you need to determine. Will you be using a normal or reverse-flow water pump? Will you be using air conditioning or removing it completely? One of the biggest questions is what type of alternator will you be using?
The great folks at Pace Performance have many choices to choose from and will be able to steer you in the right direction of the serpentine system that’s perfect for you. So now that you’ve got your system picked out and sitting in front of you, you’ll possibly have to make a few changes in the alternator wiring if you are running a non E.F.I. (fuel injected) LS motor. Working with electricity can be a tricky and sometimes dangerous activity. First and foremost; when dealing with your alternator or any other wiring, make sure your battery is completely disconnected!
Pace Performance LS3 serpentine kit. One of many different GM serpentine kits offered by Pace Performance.
The kits include an alternator connector and on this connector, only two of the four leads will be used. The markings on the connector are “SFLP” and we will be using the S & L leads. The “S” lead comes connected to the large positive stud on the rear of the alternator. A large 10 gauge wire should then be run from this stud to either the starter or connected to the positive cable on the battery terminal if it has an external lead. The next one to work on will be the “L” lead. If the car you’re installing this kit on has a “Gen” light on the dash, all you have to do is simply tie into the wire leading to the “Gen” indicator.
On G.M.-produced cars from 1971 to 1987, this will be the brown wire from the old two-wire alternator harness hookup. If your car is pre-’71, you’ll have to consult your wiring diagrams to find the correct wire. But what if this is going in a street rod or even a Ford or other manufacturer? There’s a simple way to solve this. You have to hook up the “L” lead to a 50 ohm resistor and then to a switched 12V power source. If this is not wired correctly, the alternator will fail to turn on or charge. Once you get your alternator wired up correctly and reconnect your battery, you’ll be finished with all the wiring involved with these great serpentine kits!