(continued from from 2009 Street & Tuner Milestones, by Barry Kluczyk)
Turbo vs. supercharger: The Chevy Cobalt example
When it was introduced in 2005, the Chevy Cobalt SS Supercharged (and its GM cousin, the Saturn Ion Redline) delivered performance thrills on the cheap. Its supercharged 2.0-liter engine delivered 205 horsepower and lots of low-end, neck-pulling torque (peaking at 200 lb-ft). The blower was an Eaton-manufactured Roots-type and helped the Cobalt SS hit 60 mph in about 6 seconds flat and run the quarter-mile in the mid 14-second range.
A few short model years later, the Cobalt SS was reborn with an intercooled turbocharger system generating 260 horsepower and 260 lb-ft of torque on the same basic 2.0-liter Ecotec engine platform. Not surprisingly, that extra 55 horses and 60 lb-ft of torque greatly enhanced performance, shaving about half a second off both the 0-60 and quarter-mile times.
More than that, the turbocharger system of the Cobalt SS enables greater performance through modifications of the wastegate and turbocharger itself. The previous supercharged version could be modified only through moderate means, such as a smaller-diameter drive pulley and careful tuning. Cobalt turbo tuners are easily pushing output to more than 25 pounds of boost, taking the engine past the 300-horsepower mark. Simply put, that output isn't possible with the standard supercharger on the SS Supercharged model.
Cobalt SS Supercharged engine
Cobalt SS Turbocharged engine
a typical add-on turbo kit & pricing:
Chevy Cobalt Garrett Turbo GT TunerTurbo Kit for 2005+ 2.2L Ecotec Engine Price: $2,879.99 Shipping Weight: 70.00 pounds
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