Scrolling through the vast sea of high-performance groups on social media you’re bound to see some questions about tuning late model muscle cars or other fuel-injected machines. Before you go down the EFI rabbit hole and start melting parts, though, it might be a good idea to have a high-level idea what that fancy software is changing. Thankfully, Jill Hepp from SCT is here to provide some basic information on what tuning software actually tunes.

The computer that controls your engine is monitoring countless parameters every millisecond there’s fire in the pipes, then it also has to make adjustments in that same time period based on the data it receives. Tuning software manipulates the OEM calibration data in a car with a factory ECU, or for an aftermarket system, it will access what has been programmed in by the user. There could be thousands of different scalars, functions, and tables that can be changed by a tuner to improve performance.

When you hook a laptop or a hand-held programmer up to your vehicle the tuning software will begin to interface with the ECU. When it comes time to do the tuning the software will read out the old tune, save it, add your changes to the tune, and put them back into the ECU. Hepp explains more about this process.

“Calibrators modify various pieces of this control system to optimize vehicle operation and ensure safe operation for the vehicles and its modifications. Different modifications will require different changes to the calibration. OEM calibrations also have different goals in mind compared to aftermarket custom tunes, which generally seek to optimize horsepower and torque, and create a more responsive and exciting vehicle to drive.”


What gets adjusted by the tuning software is up to the tuner, however, there are a few general areas that are targeted for performance. Depending on what your modifications or the power level of the racecar your tuning parameters like fueling, timing, boost, torque management, and transmission tuning can all be adjusted.

“Fueling is often optimized to create more horsepower and torque, while torque management is usually adjusted to reduce some of the “nannies” in the OEM programming. Variable cam timing adjustments can improve airflow which in turn creates more power and torque. Spark advance is also commonly optimized to, you guessed it, increase horsepower and torque, and adjust for various types of fuels such as pump or race gas,” Hepp says.

Hepp goes on to explain more about the other types of parameters that can be changed by tuning software for modern muscle cars that will dramatically increase performance.

“For vehicles with factory equipped turbochargers, boost pressure is usually adjusted which can dramatically increase power. For automatic transmissions, calibrators can create faster, sportier shifts, as well as optimize things like shift points and torque converter lockup. All of these things, when combined and designed by a calibrator with the proper experience and tools, provide a more exciting and engaging driving experience.”

SCT has been creating tuning solutions for those with modern EFI-controlled vehicles so they understand what’s required to put a good tune in an ECU. The new Advantage X software that SCT developed provides users with more tuning tools for their vehicle and its modifications.

“Our team has built our latest custom tuning software, Advantage X, from the ground up to ensure we are using the latest technology tools. Advantage X offers a lot of new features, with a new layout, new calculators and tools, cloud support, refreshed and optimized table and data formats, as well as a new interface that is more attractive and robust from top to bottom. The software is designed to be even faster and easier to use. Advantage X is currently in Beta testing and will be released later this year,” Hepp says.

It’s important to understand what the tuning software you’re using is modifying in the ECU before you start making big changes. Companies like SCT are able to help you grasp the basics of tuning so you can get the most out of their products.