Stage Right: The Chevy Cobalt SS Supercharged
by Todd Lamb
Prior to the Grand Am Cup race at Mid Ohio, S3 had the opportunity to thrash GM’s new sport compact around the 2.4 mile road course as only we can do – tires squealing, brakes smoldering, and engine at full song.
In stock form the Chevy Cobalt SS Supercharged puts the “sport” back into sport compact, adding levels of style, refinement and performance that appropriately far exceed that of the now extinct J-Body Cavalier. We would have been happy driving the showroom version, but GM’s High Performance Vehicle Operations let the cat out of the bag by allowing us to track test their factory Stage 1 and Stage 2 upgrades that are currently undergoing CARB certification and will hopefully be released around SEMA time in November.
The Stage 1 kit includes higher flow injectors and a new PCM calibration. The injectors give the engine enough fuel to rev higher, and the new engine calibration allows it all to happen by raising the rev limiter to 6700rpm. The new calibration also allows full boost instead of limiting it to a 205hp maximum with the stock PCM. We found the Stage 1 to be a modest improvement over the stock configuration, but perhaps that’s because we knew the best was yet to come.
Stage 2 adds the same injectors and calibration as Stage 1, but also includes a smaller 79mm supercharger pulley which increases boost by 2psi. According to Jim Minneker, Engineering Group Manager at GM HPVO, the Stage 1 calibration is configured to account for the smaller pulley if it is added, so there’s no need for different calibrations for each stage. Based on our experience, it’s not so much a matter of if you’ll want to add the pulley, but when.
We’ve been preaching that peak horsepower numbers don’t mean a thing for years, and while the Stage 2 package doesn’t deliver much additional peak horsepower over Stage 1, it provides what matters most – torque. We found the torque to be a vast increase over Stage 1, resulting in 10mph more straightaway speed and monster acceleration off corners. The Stage 2 setup is very similar to what is being run on the Grand Am Cup Cobalt. Like the winning race team we found the extra boost and torque from the smaller supercharger pulley to be much to our liking, especially while accelerating down Mid Ohio’s long backstretch.
If you are interested in more ECOTEC mods, check out the GM Sport Compact Performance Build Book (p/n 88958646). It contains all the go-fast parts for anything up to 1400hp and even details some of the basics to build your very own Cobalt Grand Am Cup car. These downloads are provided here on FastFieros FastTech section for FREE !