Years ago, one way to get a little more power to your ignition system was to get aftermarket components. This typically meant new spark plug wires, a new coil, and often times this upgrade meant utilizing an aftermarket digital ignition box as well. We see these upgrades on lots of classic musclecars, and some musclecars up through the 80s and 90s – cars with distributors, to be specific.
But many engines these days don’t have the typical ignition set up, and instead of long spark plug wires, a distributor, and a single coil, there are short ignition wires that run directly from their own coil to the spark plug. It does make things easier, and simplifies the parts for the ignition, but leaves many owners with few choices when it comes to upgrades and performance.
This type of ignition system is called a direct ignition system, and sometimes these ignition systems use a Coil Over Plug (COP), which doesn’t have any spark plug wires at all because the coil plugs directly on top of the spark plug itself.
With ignition systems using long spark plug wires, consider that eight different length wires deliver eight different amounts of resistance. As small as it is, there is still resistance when the spark travels from the distributor to the spark plug. Direct ignition eliminates the resistance found in spark plug wires.
Sparking Up The Debate
We wanted to see just how much of an increase we could get from installing a set of COPs from Performance Distributors. We’ve all heard manufacturers tell us that their product will give you an increase in horsepower, and we’ve even seen claims that were so outrageous that they’ve made us skeptical right from the start.
Who can forget the electric superchargers that claimed horsepower gains, when all it did was make a lot of noise and restrict airflow? We don’t like gimmicks, and neither does Performance Distributors, that’s why they sell proven products and not electric superchargers.
But can something as simple as a COP actually give you better performance and more horsepower? Typically we think about horsepower gains in terms of installing something that is more mechanical, not by adding an electrical part. So we put the Sultans of Spark to the test in our shop and we’re ready to share the results with you.
Our test car is a 2007 Dodge Magnum with a modified 5.7L HEMI. By modified, we mean that it’s sporting a Vortech V3 Supercharger and charge cooler, SLP headers and a Flowmaster exhaust, with a DiabloSport Trinity T1000 tuning system. We’re already seeing some extra ponies out of this HEMI, but will we see even more with an upgrade that has no moving parts?
Our 5.7L HEMI has dual plugs, but they do a bit more than just add to the overall cost of spark plugs. The dual plugs help the HEMI to run more efficiently, and to help reduce emissions. The dual plugs reportedly provide a more complete burn of the fuel in the combustion chamber, and also help smooth out the idle. Still, we’re adding more voltage, and this will enhance the “fire in the hole” even more.
We also decided that replacing the spark plugs during the coil swap was a good idea. Changing spark plugs with this type of ignition system is a bit more involved, and it simply made sense to do so during this swap.
Ohms Law: Voltage = Current x Resistance
When it comes to factory ignition upgrades, companies like Performance Distributors have developed aftermarket COPs to provide enthusiasts with the benefits we mentioned above – better economy and a more complete burn. These COPs, that Performance Distributors calls Sultans Of Spark, improve upon the factory design with better conductivity and better quality materials.
When the spark plug gets its juice from the factory coil, there is an inherent current loss that occurs when the spark travels down the coiled wire inside the COP. This creates some surface loss because the current doesn’t travel inside of the wire, it travels on the surface of the wire. This surface loss can be equated to resistance, which can reduce the current and/or the voltage. This is one of the three basic mathematical equations for Ohms Law, which is the relationship between electrical voltage, current and resistance.
Inside the COP, making the connection from the coil to the spark plug is a coiled wire, like a spring, that transfers the current to the spark plug. There is a lot of surface area for this type of set up, and the spark has a lot of area to cover. With lower quality materials and thinner wire, this equates to higher resistance. If you’ve seen your headlights dim when you put your foot on the brake, then you know how resistance can zap the energy out of an electrical system. The more demand there is from your electronics, the more the output is affected by resistance in the system.
With Performance Distributors’ new Sultans of Spark COPs, you can get back some of that lost energy because these COPs are designed to give you up to 50% more spark – up to 40,000 volts. The higher voltage and spark duration allow you to open up the gap on your spark plugs to .065 inches, which gives you a bigger and hotter spark inside the cylinder.
The larger diameter windings will keep the voltage to 40,000 at idle, and under load. -Steve Davis
A bigger spark means a more complete burn of the fuel in the combustion chamber, resulting in more horsepower and better fuel economy. That means that you’ll be burning the fuel more completely instead of dumping it out the exhaust.
We spoke to Steve Davis, owner of Performance Distributors, and asked about the Sultans of Spark. He told us, “The factory coils run about 30,000 to 35,000 volts at idle, but under load the voltage drops considerably. We went in and took out some of the windings and made them larger, with less resistance. The larger diameter windings will keep the voltage to 40,000 at idle, and under load. This improvement over the stock coils means that the higher voltage is going to give you a better spark to burn the fuel more and increase the horsepower.”
But having a better spark helps out in many other ways, too. Better starting, smoother idle and quicker throttle responses can be experienced as well. With all these benefits, you have every reason to step up to the new Sultans of Spark COPs from Performance Distributors. At the risk of sounding too cliche, they will eventually pay for themselves.
Installing The Sultans Of Spark COPs
On a typical, normally aspirated HEMI, there is one component that isn’t on our Magnum, and that’s the engine cover. That will need to be removed for access to the COPs and spark plugs. On our Magnum, the engine cover was removed when the Vortech Supercharger was installed to make room for the charge air cooler.
The coils come off fairly easily, just two small bolts per coil and one weatherproof electrical connection. The wire harness makes it difficult to reconnect the plugs incorrectly, but always be sure that the connections are put back in the correct location when you’re putting it all back together.
The instructions from Performance Distributors for a normally aspirated car stated to gap the plugs to .065. But for forced induction, like our Magnum, we gapped all 16 spark plugs to .040 and used anti-seize on the threads before replacing the spark plugs. Anti-seize will keep the threads from galling, and make it a little easier to remove the plugs again when they need to be replaced. With the additional air forced in with the blower, backing the gap down to .040 is more efficient, and that allowed us to find a little more horsepower.
With the plugs installed, we installed the new Performance Distributors’ Sultans of Spark COPs and bolted them down with the supplied hardware, and reconnected the harness to each coil. The entire process takes very little time, so it should only take you an afternoon to replace the coils on a stock HEMI. It’s also a good idea to put a little die-electric grease inside the spark plugs boots to help with the seal, and to keep moisture out. It also acts as a barrier for dirt, and keeps the boot from sticking to the porcelain on the spark plug.
After reinstalling the charge air cooler, we were ready to get the Magnum back on the dyno to see the results. Prior to installing the COPs we saw 423.74 RWHP. Remember, this was with a slightly modified HEMI with a Vortech Supercharger, SLP Headers, Flowmaster exhaust and DiabloSport tuner. So we were already seeing higher numbers than a stock Dodge Magnum, thanks to the existing power-adder.
Once we got the car strapped down again to the dyno, we made some adjustments to the DiabloSport Trinity to get the optimum power with the new coils. Initially we saw a slight increase, but knew that we were getting more voltage and therefore could make some simple tuning adjustments to capitalize on that.
With the latest tune we were able to see an increase of 6.26 RWHP, spinning the drums at 430.00 RWHP and similar torque. In addition to the added power, we also noticed that the air/fuel ratio (inset) also cleaned up quite a bit and wasn’t all over the place, fattening it up a little bit to clean up a lean condition that could have caused a little detonation – which is not good for a boosted vehicle making this kind of horsepower.
While we didn’t expect to see a huge power increase with the addition of more powerful coils, we were pleased to see that we did see an overall increase in horsepower at the rear wheels. This installation shows that we still had a little room for improvement over the stock ignition system, and the Sultans Of Spark, from Performance Distributors, were able to help us utilize the energy a little more and turn that extra voltage into a few horsepower.
Davis told us, “We’ve been doing some of our own testing with normally aspirated vehicles and our results are right in line with what you’ve found with a boosted application.” So whether you have a blown HEMI or your vehicle is just the way it came from the factory, the Sultans of Spark COPs are delivering a nice little boost of their own to your spark plugs.
With a better running HEMI, a little more horsepower under the right foot and a smoother air/fuel ratio, the Magnum should see a little better economy at the pump, too, providing that extra horsepower isn’t being summoned at every stoplight or cross street. Be sure to check out the Performance Distributors web site and see if they have a set of COPs for your HEMI Mopar or your 2-, 3-, or 4-valve Ford engine. It may be hard to believe that a coil can increase horsepower, but we were happy with the increase that we saw, thanks to the Sultans Of Spark!