The production Ecotec—available in the Chevrolet Cavalier, Pontiac Sunfire, Pontiac Grand Am, Oldsmobile Alero, Saturn L-Series and VUE in North America, as well as Opel and Saab models in Europe—is a 2.2-L, 16-valve, four-cylinder DOHC engine. As part of GM's global four-cylinder family, the production engine was developed by an international team that included engineers from Opel's International Technical Development Center in Russelsheim, Germany; GM Powertrain in Pontiac, MI; and Saab in Trollhaten, Sweden. The production Ecotec—depending on vehicle application—produces between 100 and 107 kW (135 and 143 hp) with a torque between 193 and 206 N•m (142 and 152 lb•ft).
"We're currently at the 800-hp level after starting with about 140 hp with the production engine as installed in a production car," said O'Blenes. "We were able to make between 370 and 400 hp with billet rods and forged pistons with everything else stock."
The production engine underwent various alterations, including the aluminum block (modified with stainless steel O-rings and copper head gaskets to withstand cylinder pressure resulting from the turbocharger); cylinder heads (ported and outfitted with dual-coil valve springs and titanium retainers—support was added for the numbers 1 and 4 combustion chamber); camshaft drive gears (slotted to allow adjustments in camshaft phasing); and camshaft drive (stock timing chain, guides, and hydraulic tensioner). "We were able to start with a really good base engine package," said O'Blenes.
In addition to retaining stock components whenever possible, goals of the racing engine program centered on producing more than 447 kW (600 hp) for the Sunfire application (which uses no intercooler) and more than 522 kW (700 hp) for the Cavalier application (which allows an intercooler). The desired power band was targeted from 5500 to 9200 rpm. GM Racing also wanted the durability to make 25 full power sprints between engine rebuilds. The program exceeded on all counts.
Early in the race season, the power band was ranging between 5500 and 9700 rpm, while engine durability was allowing between 35 and 55 full passes between rebuilds. To reach over 578 kW (775 hp), three primary aspects were key to the power supply. "The heart of it is in the cylinder heads—machining the ports to increase the airflow; the camshaft profiles—more lift and more duration; and the turbo,"