General Motors' new Ecotec-powered front-wheel-drive drag cars will undoubtedly dazzle spectators with their raw power and lightening-fast acceleration, but the foundation for their high level of performance is rooted in a powerplant that serves a variety of platforms for the automaker's global brands.
The Ecotec 2.2-liter four-cylinder engine is GM's first truly global powerplant. In production trim, the Ecotec delivers exceptional fuel economy and low exhaust emissions in a reliable, low-maintenance package. In racing trim, it delivers astounding horsepower.
Consider that the turbocharged Ecotec that powers the front-wheel-drive Cavalier drag racer, which will run in the National Hot Rod Association (NHRA) Modified class and the Import Drag Racing Circuit (IDRC) Outlaw class, produces more than 700 horsepower from only 120 cubic inches of piston displacement - a staggering 5.8 horsepower per cubic inch (its Sunfire sibling that will run in the NHRA Hot Rod class and IDRC Quick class produces 600 horsepower for 5hp/cu.-in.). If a naturally aspirated 500ci Pro Stock engine had equivalent output, it would produce nearly 3,000 horsepower!
"The Ecotec engine development program is running parallel with the 500-cubic-inch engine Pro Stock program," said Herb Fishel, Executive Director of GM Racing. "We are really excited about the performance potential of the Ecotec engine."
The Ecotec debuted in the 2000 Saturn L-Series, and is used in several European applications, including the Opel Vectra, Astra, Zafira and Speedster models. This lightweight aluminum four-valve, DOHC engine is also now available in the 2002 Chevrolet Cavalier, Pontiac Sunfire and Grand Am, Olds Alero, Saturn VUE.
The race-prepared Ecotec engine enjoys certain advantages in addition to its pressurized induction system. First is its robust construction, a trait it inherited directly from its production counterpart. The Ecotec block's rigid bottom end resembles a classic racing engine, with a one-piece casting that incorporates the five main bearing caps (each retained by four fasteners) and mounts a structural cast-aluminum oil pan. The stock four-valve aluminum cylinder head's generously sized intake and exhaust ports provide excellent airflow (250cfm at .400-inch intake valve lift), while a single centrally located spark plug in each pent-roof combustion chamber provides fast, efficient combustion. The two overhead camshafts actuate the inlet and exhaust valves via roller finger follower rocker arms - another design feature utilized by many high-rpm racing engines.
The Ecotec drag race engine builds on the strengths of these production components. GM Racing engineers Russ O'Blenes and Josh Peterson retained the stock block and head castings. The block was modified with stainless steel O-rings and copper head gaskets to withstand the extreme cylinder pressure produced by turbocharging. The cylinder heads were ported and outfitted with dual-coil valve springs and titanium retainers; reground production camshafts actuate the valves through stock finger followers. The original camshaft drive gears were slotted to allow adjustments in camshaft phasing. The camshaft drive uses a stock timing chain, guides and hydraulic tensioner.
Heavy-duty components replaced the production crankshaft assembly. A de-stroked billet steel crankshaft, steel H-beam connecting rods with high-strength bolts, forged aluminum pistons and thick-wall piston pins were designed to GM Racing's specifications. The crankshaft rotates in production thick-wall main bearing inserts.
A custom-built dry-sump oiling system with a five-stage pump provides reliable lubrication at high rpm in the Cavalier (a stock wet sump oil system is used in the Sunfire). An electronic fuel injection system meters methanol into a fabricated aluminum intake manifold. The production water pump and alternator were retained.
The goals of the Ecotec drag race engine program were to produce 600 horsepower for the Sunfire and 700+ horsepower for the Cavalier, a power band that stretched from 5,500 to 9,200 rpm, and the durability to make 25 full-power passes between rebuilds while retaining stock components whenever possible. By exceeding every one of these objectives, the race-prepared Ecotec engine promises to make the Chevy Cavalier and Pontiac Sunfire frontrunners in their respective classes in front-wheel-drive drag racing and forerunners of a new generation of GM four-cylinder performance engines.
The Ecotec engine was developed by an international team of 230 engineers and technicians that included personnel from Opel's International Technical Development Center in Rüsselsheim, Germany, GM Powertrain in Pontiac, Mich., and Saab in Trollhäten, Sweden. All of the engine components were modeled in three dimensions using GM's state-of-the-art computer-aided design software. The Ecotec engine design will power a wide variety of GM vehicles worldwide with displacements ranging from 1.8 to 2.2 liters.