VORTEC 4200 4.2L I-6 (LL8) 2006 model year summary ? Increased horsepower and torque outputs ? Higher 10.3:1 compression ratio ? Improved air flow ? Mass air flow sensor ? Improved A.I.R. system ? Improved ignition coils ? Piston rod squirters Full descriptions of new or changed features Increased horsepower and torque. The Vortec 4200, already noted for providing peak power and torque emulating that of competitors? larger-displacement V-8s, delivers 16 more horsepower for 2006. Its new rating is 291 hp and 277 lb.-ft. of torque. The power increase resulted from a higher compression ratio and improved engine breathing. GM Powertrain?s participation in the new SAE test certification procedure provides more accurate readings of in-vehicle performance by using more exact measures of exhaust backpressure and also accounting for loads put on the engine by the accessory drive. Increased compression ratio: The Vortec 4200?s compression ratio increased to 10.3:1 as a result of changes to its piston profile, which lowered the volume in the combustion chamber. Even with its higher compression ratio, the engine continues to maximize fuel economy by allowing customers to use regular or unleaded fuel. Improved air flow: Improved performance also results from increased airflow into and through the engine. A larger (38.7 mm) intake valve and larger (33.5 mm) exhaust valve allow more air to flow through, and the camshaft also provides more lift to allow the valves to stay open longer. Mass air flow sensor: A mass air flow system helps reduce emissions, allowing the Vortec 4200 to meet California LEV II emissions requirements while also improving its fuel economy. The mass air flow (MAF) sensor (replacing a previous speed density fuel control system) more accurately measures air flow into the engine, eliminating variability in a number of conditions including changes in altitude and temperature, and allows more precise fuel and spark response. The MAF is lightweight and has a modular design, using an integrated intake air temperature sensor. The electronics, located in the center of the sensor?s flow tube, areair cooled by the intake air. The output calibration is precisely programmed into the module. A.I.R. system: The Air Injection Reaction (A.I.R) System, which pumps air into the port of each cylinder head, has also been upgraded to assist in reducing emissions. During the casting process, the A.I.R. port is now cast right into the cylinder head for improved air flow. Ignition coils: The ignition system uses more compact coils, which also provide better reliability/ durability and make better use of its energy. Their more compact size saves an entire coil?s worth of weight. Enhanced durability has been proven from the coils? use in other Gen III engines. Piston rod oil squirters: The piston, inside the cylinder bore of the engine block, transfers energy through the connecting rod to the crankshaft. For improved durability and quietness the piston rod is now drilled with a tiny (less than 1/8th mm) hole, which allows oil to be sprayed on the cylinder wall, providing a cushioning layer on the sides of the piston which rides on the film of oil. The oil is originally pumped into the crankshaft, whose journals have cross-drilled holes. As the crankshaft rotates, pumping oil through the journals, the oil is fed from the journals through the piston rod bearing into the piston rod itself. Its open orifice then allows the oil to be sprayed into the cylinder wall. Overview: In 2003, the Vortec 4200 was fitted with polymer-coated pistons that reduce engine noise and enhance durability. The oil pump was refined to limit noise; and the cam-chain tensioner was improved for quieter operation. For model year 2004, the Vortec 4200 was introduced in the all-new Buick Rainier and Isuzu Ascender. In ?05 its variable valve timing, or cam phasing, system was equipped with a new state-of-the-art vane phaser. Along with previous GM midsize SUVs, ?05 also saw the Vortec 4200 introduced in the Saab?s first 9-7X SUV. The Vortec 4200 originally debuted as the first inline six-cylinder engine in GM Powertrain?s lineup in nearly 20 years. While the industry largely had turned away from the inline six, GM recognized that, given careful design and development, the inherent advantages of inline six-cylinder architecture were perfect for the new millennium. An exceptionally light, rigid engine block and cylinder head combination, cast with the GM's patented lost foam process, provide the foundation for the Vortec 4200?s success. All-aluminum construction means less weight than conventional cast- iron truck engines, and less weight means improved fuel economy. The bottom end of the engine derives strength through many features, starting with a bearing beam, or ladder, that connects the seven main bearing caps to further stiffen the engine?s structure. The oil pan bolts to the transmission bell housing as well as the engine block, eliminating points of vibration and making the complete engine more like a single casting. The oil pan also gives ?panaxle? all-wheel drive capability to trucks equipped with the Vortec 4200. A passage cast through the width of the oil pan allows a drive axle to pass through it rather than under it, allowing the engine to be placed lower in the vehicle for a more compact package that improves the vehicle?s handling dynamics and gives designers greater styling flexibility. The Vortec 4200's feature list reads like those for premium luxury/performance car engines: dual-overhead cam cylinder head, four valves per cylinder, roller-follower valve actuation and exhaust-cam phasing; a 10.3:1 compression ratio that delivers the seemingly incompatible benefits of high compression and regular-grade fuel; Electronic Throttle Control (ETC); and direct accessory mounting. Vehicle platform teams recognize the Vortec 4200?s strengths, yet its design advantages and premium features mean little if the finished product doesn?t deliver what customers demand, like low maintenance. With Vortec 4200, oil changes are the only scheduled maintenance during the first 100,000 miles of operation, and even those are as stressfree as possible. GM?s Oil Life System (GMOLS) advises an oil change when it?s actually needed, based on real-world vehicle operation, rather than a predetermined mileage interval. The Vortec 4200 is produced in Flint, Michigan. Brien. NEW YORK eagle registry #501 eagle kammback registry