One area on an LS engine that often gets overlooked is the ignition system and for a good reason. Chevrolet did an excellent job on its coil set up for the LS and the LT engines. And while this system works very well, there’s room for improvement. But you may be thinking, “What’s to gain by switching up the ignition coils?” This is a fair question and one that LS enthusiasts will argue over time and time again. While you’re not going to gain 50 horsepower by swapping out your coils and plug wires, there are significant gains to be had.
Recently we finished up an LS-swap on a 1991 Suburban. We like to take this beastly machine on road trips, offroad expeditions, and it’s been up to the mountains for ski season a time or two. The last thing we want to deal with on the road is parts failure. Since the vehicle has a factory ignition system that is almost 20 years old, we decided to upgrade the coils and wires. Instead of using the factory coils and plug wires, we chose to update these components with SOS (Sultans Of Spark) Coils and LiveWires spark plug wires from Performance Distributors.
The SOS coils are designed to fit the 1997-2019 General Motors LS and Vortec engines. As expected, these coils pack a punch with additional voltage over the factory units. The SOS line offers 7,000 more volts per coil for a total of 56,000 added volts for our LS engine. This extra energy will produce more horsepower, increase throttle response, fuel economy, allow for quicker starting, and offer a smoother idle. Since the Suburban is driven quite often, all of these benefits are welcomed, but we are especially excited about any increase in fuel mileage.
So, why do the SOS coils create so much more voltage over the stock units? After all, they are the same size as the factory parts.
Performance Distributors uses the latest technology to enhance the coil windings for higher output while retaining the original sizes. These units use thermal epoxy, which improves heat transfer and vibration protection. Brass terminals are also used for enhanced conduction and less chance of corrosion.
For our application, we decided to use ICT Billet‘s coil mounts instead of the factory stamped black brackets. These units look much better than the OEM parts and clean up the engine bay nicely. The brackets included all of the necessary hardware and were a perfect fit. We simply removed the old coils, and the new ITC Billit units bolted into place. The SOS coils use the factory wiring harness, making this installation a simple plug-in-play.
Another area that we needed to address for our newly added voltage was the spark plugs. Performance Distributors recommends increasing the gap from the factory gap to .065-inches. This larger gap causes the spark to travel a longer distance allowing for more coverage while igniting more fuel in the cylinder. After we had the plugs back in place, it was time to put on the LiveWires.
According to Performance Distributors, “LiveWires are a high quality, low resistance set of spark plug wires designed to deliver all of the spark energy from the coil to the plugs.” This product uses a high-temperature sleeve that protects the plug wire from the intense temperatures in an engine compartment. In fact, the non-flammable sleeving provides up to 1,400-plus degrees of heat shielding and is resistant to chemicals as well as moister. Inside this durable shielding is an 8mm spiral core with an enduring silicone jacket. The spiral core design uses a stainless steel wire wrapped around a magnetic core offering a resistance value of 300-350 Ohms per foot. While the LiveWires offer maximum spark travel, the spiral core wire is also a radio suppressant meaning; they will not interfere with electronics such as a radio or delay boxes. LiveWires are available in a variety of colors, applications, and come preassembled with a tube of dielectric grease.
We loved the fact that the wires are preassembled, and we didn’t have to fumble around and build them like some of the universal kits on the market. We applied the included dielectric grease and slid on the plug wires. While our factory spark plugs cleared the Doug Thorley headers, we didn’t have much leeway. We were delighted to see that the LiveWires had 45-degree boots on both ends of the plug wires. These boots allow for ample room next to the header tubes.
With Performance Distributors products installed, we hit the ignition switch, and the engine immediately fired up. We noticed that the 5.3 did seem to start quicker than usual. We really couldn’t tell if the mill ran any smoother due to the large Comp Cams camshaft that was thumping away, but it sounds healthy. After driving the Suburban around seemed to be running better than ever in stop and go traffic. The best part is all of the old ignition components are gone, and we won’t have to worry about replacing a coil here and there as they break down.
Now if someone could just keep their right foot out of that pedal to see how much the gas mileage increase.