Welcome to the enthusiasts’ technical resource for the 205 hp General Motors (GM) Ecotec 2.0L four-cylinder supercharged engine (RPO–LSJ). This engine, which powers the 2005-7 Chevrolet Cobalt SS Supercharged and 2004-7 Saturn Ion Red Line performance vehicles, and is also available as a crate engine (P/N12499466), has a strong following on the street for its impressive power output and durability along with its ability to be easily upgraded in power output. The “LSJ”engine is so called because on the vehicle build sheet the Regular Production Option(RPO) designation (see sidebar for more on RPOs) for this engine is “LSJ”—which hasled to enthusiasts referring to this engine as the “LSJ” engine. ECOTEC Component Comments 1 The ECOTEC LSJ Story Engine Block Lost foam and sand cast aluminum with pressed-in cast iron cylinder liners, four bolts per cylinder, setup up for twin bal-ance shaft vibration cancelling system. Main Bearing Girdle Lost foam cast aluminum integral main caps held in place with ‘torque-to-yield’fasteners. Cylinder Head Cast aluminum with dual overhead camshafts, design capable of supporting active camshaft phasing for variable valve timing, direct fuel injection and more… Crankshaft The 2.2L and 2.4L Ecotecs have a castiron crank. The LSJ crankshaft is a forged steel design that incorporates induction heat-treated fillets for added strength, and cross-drilled, chamfered oil passages for excellent lubrication charac-teristics. Connecting Rods The 2.2L and 2.4L Ecotec engines come with powdered steel rods, while the 2.0Lengines have forged steel, large I-beam rods. Pistons All the Ecotec engines come witheutectic cast aluminum pistons. The common pistons in the Supercharged and Turbocharged Ecotec engines have a5.6 mm top ring land, much thicker crown & strut sections, coupled to aheavy walled 23 mm piston pin. Piston Rings The LSJ uses a 1.15 mm Chrom-Keramik top piston ring, a 1.45 mm napier phosphate coated second ring and a 2.5 mmdual rail with expander design oil control ring. Valve rain The Ecotec cylinder head has 16 valves at 35.1 mm intake and 28 mm exhaust diameters. Valve actuation is accomplished via lightweight, direct-acting cam followers (what looks like an upside-down rocker from a pushrod engine) pivoting on stationary hydraulic lifters. The lobes of the two camshafts press on these cam followers, which inturn open and close the valves. The system is compact, durable and elegantly simple—and it works! Crank Trigger Early Ecotec engines used a 7x crank trigger (which means the wheel on the crank had 7 notches in it for the computer to ‘read’ to determine what inputs to apply to make it run), but as of 2007,all Ecotec engines have a 58x crank trigger (which is the new global standard for engine controls).

Download Get the Most from the ECOTEC 2.0L Inline 4-Cylinder LSJ Engine.