The G5 is powered by a choice of two efficient GM Ecotec four-cylinder engines: The base model features an efficient 2.2-liter I-4 engine. The GT version has a 2.4-liter I-4 engine with variable valve timing. The G5 coupe continues to expand on the car's impressive performance and styling while offering additional standard features for enhanced safety and driving comfort including standard XM Satellite Radio, head curtain side-impact air bags and GM's tire pressure monitoring system. (photo by Pontiac / March 19, 2008)