We’re back on the DynoJet...
We’re back on the DynoJet to demonstrate how Ryan Krummick of SCT Performance tuned our ’05 GTO. Before making any changes, Ryan reviewed the modifications we made to the vehicle and looked over our previous and current tune files. This allows him to make a safe, conservative tune to initially load into the Pontiac.
Tuning is the origin of hot rodding. Back in the day, Pontiac owners with a taste for performance would dial in their cars' air/fuel ratios and timing among other things to squeeze a few more ponies out of their engines. As aftermarket parts became more widely available, tuning was performed to compensate for the operating characteristics of the new parts, make the most of their attributes by unleashing hidden horsepower, and ensure safe engine operation.
With the advent of electronic fuel injection, tuning became a totally different animal that today involves modifying the Electrically Erasable Programmable Read-Only Memory (EEPROM) within the vehicle's Engine Control Module (ECM) via a laptop and software and/or a handheld controller. Some fear that all this technology is too complex for the average hobbyist to tune, however, one quick look at this or any other car magazine's advertisers shows that tuners have popped up around the world, all touting they have the perfect performance file to upload to your engine's computer brain.
It wasn't really until after LS-engine ECMs arrived in '97 ('98 for the Trans Am or Formula Firebird) that EFI tuning really began to take off for the GM market. These tuners can be classified in two types—handheld and laptop.
For the first series of pulls,...
For the first series of pulls, Ryan wasn’t concerned with power. He was focused on the data being gathered by the LiveLink software as he brought the car up to 4,500 rpm.
Handheld tuners are generally used for ballpark, safe tunes with bolt-ons that only require simple yes or no answers to load a program that may moderately increase performance and retain engine safety. Many hobbyists prefer them because of their convenience, relatively cheap price, and user-friendly design. However, owners looking for the most out of their engines may be a bit disappointed by these handheld, high-performance helpers. Unless you have a pair of eyes looking into the tune and then make more in-depth adjustments, there may be power left on the table.
Windows-based software applications like LS1edit and HP Tuners answered the call for a learnable method to create more comprehensive tunes. These programs allow for more fine-tuning of the factory ECM and have quickly become the preferred method for tuning in the high-performance LS aftermarket.
About SCT
SCT Performance got its foot in the door of the tuning aftermarket in 1996 with Mustangs, but has recently ramped up its focus on GM vehicles with its latest plug-and-play tuning software, Advantage III. It's used in over 26 countries and by over 1,100 custom-tuning shops, speed-product manufacturers, and OE performance-solution providers worldwide.
SCT's X3 tuner, which uses the Advantage III software, is the latest in the company's consumer-friendly handheld tuners. It bridges the gap between traditional handhelds and the more powerful software-based tuners.
After completing a series...
After completing a series of pulls, Ryan felt that he had enough data to review. By comparing the air/fuel commanded versus the air/fuel experienced, he could then begin to add timing and see power gains.
The X3 reads and reprograms the ECM and Transmission Control Module (TCM) data files, unlike many of today's popular handhelds, which only reprogram the ECM. With a wired connection to a laptop, users can download the free SCT LiveLink software and datalog—something no other competing handheld can do.
The X3 can also store three tunes. "This allows the car owner to have an economy tune, a performance tune, and a valet tune stored, if they desire," Ryan Krummick of SCT tells us.
Another feature we find promising is the device's level of connectivity to a PC. After data logging, a remote tuner can review the information and then email a new tune that can be uploaded to the ECM through the X3. This means that even in the most remote parts of the world, your Pontiac can be tuned as long as you have Internet access and a PC.
Tuning Methodology
We recently installed a TrickFlow heads-and-cam package on our LS2 in our '05 GTO and were in need of a custom tune. Ryan came from SCT's home base in Longwood, Florida, to the High Performance Pontiac Tech Center in Tampa and walked us through his tuning steps using the SCT X3 and LiveLink.