A tuner downloads new high performance tuning information to your vehicle's computer, and stores the original information in case you ever want to go back (you won't). The real value of a tuner is the work and experience that goes into that new tuning setup for your vehicle. You don't get that expertise by being in the business for just a few years.
At Superchips, their engineering teams adjust all of the elements that affect vehicle power: air/fuel ratio, fuel injector flow rates and spark timing. They also tune shift characteristics of an automatic transmission for maximum acceleration and a high performance driving feel.
Thirty years ago, these results would have required rejetting a carburetor, reworking the spark advance on the distributor and installing a transmission shift-improvement kit. Today, it's knowing how to read fuel and spark maps, knowing exactly where to push the limits and testing, testing, testing.
There are several key factors to creating a tune for your vehicle. First, it has to maximize power without causing you headaches. That means no broken parts caused by the increased power. One of the measurements Superchips use in their testing is Exhaust Gas Temperature (EGT). This is especially critical in turbo diesel applications. It's easy to create really impressive power increases for these vehicles, but a skyrocketing EGT is going to lead to broken engine parts, no questions asked.