The Cobalt engine will not fit without extensive modifications. Your best bet is to try to get your engine built up. The only engines that could readily be used ,in America, is the 1.8 or the 2.0 from an early 90s Pontiac Sunbird, or the 2.0 from a Suzuki Reno/Forenza. You could have one shipped from Europe. Practically any Vauxhall/Opel/Daewoo engine will fit without major modifications. They have some pretty good performance engines over there. C20XE, C20LET are good engines you could use.