Spark Plug Tips for Boosted Engines
By Erik Radzins Director of Communications, ProCharger Superchargers
Spark plugs can make or break your car’s engine power, especially when it comes to power adders.
There are several factors to consider to make sure you have the best horsepower gain after you supercharge your vehicle.
Heat range is one of the most common things you can (and should) change when you add boost. The heat range is the spark plug’s ability to pull heat out of the chamber or away from the tip. Pulling that heat away means less chance for detonation. However,
a little bit colder is good. A lot colder is bad.
Gap is another key consideration. Adding boost adds cylinder pressure inside the combustion chamber. When that spark has to jump the gap, it now has to do so amidst all that extra pressure. To ensure that a spark fires properly every time, you must close down the gap, making it easier for the spark to jump from the
Spark plugs can help you make horsepower, or not if you make a mistake. Our simple tips will help you bypass common issues.
ground strap to the electrode.
Spark plug tip style is affected by your engine design. Different cylinder heads have different spark plug location, depth, and position in the combustion chamber, affecting how the spark plug tip sticks out into the air fuel mixture. A common misstep we see is people will run a non-projected tip plug in a head that required a projected tip.
Tip material initiates a lot of questions, because people are concerned that an iridium or platinum plug is too hot and will hurt their engine. Rest assured, this is not the case. Any material will work on a supercharged vehicle. The key difference is that copper plugs are going to wear faster and will need to be changed out more frequently, while platinums and iridiums were designed to go much longer without a spark plug change.
Boost adds cylinder pressure inside the combustion chamber, so you need to decrease the spark plug gap to ensure the spark successfully jumps to the other side.
A common misstep we see is people will run a non-projected tip plug in a head that required a projected tip.
Spark plugs come in all shapes and sizes, like this interesting ground strap style. Reach out to a spark plug manufacturer if you are curious about how a unique spark plug will perform with your engine.
It is equally important to replace your spark plug wires regularly to avoid misfires.
Breakup problems is another spark plug topic that requires explanation. Be mindful about buying spark plugs with a resistor. Any modern car with electronic components will require a resistor style plug, while older carbureted vehicles with no electronics can get away with a non-resistor plug.
When it comes to reading a spark plug, it can be more challenging
than you think. To read a spark plug properly, you need to install brand new spark plugs and test on a dyno or a track. Run a cycle and shut the car off at the very top of the run, then read the spark plug for clues as to what happened right before the engine was shut down.
Before you buy your next set of spark plugs, we have a couple recommendations. First, replace your
coil wires regularly to avoid misfires. Second, use the tool made for gapping plugs, because the fragile porcelain, copper, and connections are easily broken. Third, it is worth your while to reach out to a spark plug manufacturer. We’ve always found them to be quite helpful.