SPORT COMPACT TECH:
GM's ECOTEC Engine Pushes Into New Frontier of High Performance

By Jennifer Chestnut

DETROIT, September 3, 2002 - When GM Racing engineers were assigned the task of developing a competitive power plant for their new Sport-Compact Drag Racing program, the ECOTEC 2.2-liter four-cylinder engine provided a solid platform for them to launch this ambitious program. Now after almost 16 months of intense research and development work, and with the completion in sight of GM Racing's first full season of sport-compact drag racing, the turbocharged ECOTEC 2.2-liter engine used in this endeavor is rocketing towards uncharted territory.

"The durability of ECOTEC's production piece is unbelievable," said Russ O'Blenes, GM Racing engine program manager. "When we first started on this project, the fundamentals of strength and endurance needed to get the job done were already in place. We've taken production engines, abused them and tried to hurt them in every which way, and it's just hard to hurt one of these bad boys."

Starting with a bone stock ECOTEC 2.2-liter engine in April, 2001, O'Blenes and Steve Bothwell, engine development manager at Bothwell Racing, were able to produce 140 horsepower using a dyno at Shaver Specialty Engines in Torrence, Calif. By removing the exhaust system from the ECOTEC they were successful in increasing the horsepower reading to 170. Adding nitrous to the ECOTEC power plant raised the horsepower output to approximately 250.

After evaluating their data, GM Racing engineers made changes to the connecting rods and pistons. Using nitrous, ECOTEC's power output increased to approximately 350 horsepower.

Since the cylinder block on the ECOTEC is an open deck, which means the cylinder walls float freely, GM Racing engineers machined-out the cylinder walls and made their own steel sleeves that were pressed to the block. At 500 horsepower there was also a change from the production head gasket to a copper head gasket with O-rings.

GM Racing engineers then began weaning the ECOTEC off nitrous, added a turbocharger, and increased the air flow in the cylinder heads by opening up the intake and exhaust ports, taking the horsepower level up to 650. By making additional changes in the cylinder lining and cylinder heads, GM Racing engineers have been steadily increasing the ECOTEC's output to where they are now on the threshold of 1000 horsepower!

"A major portion of the parts that we use on our ECOTEC race engine are currently production pieces," said Bothwell. "We've performed modifications to the crankshaft, the connecting rods and the pistons. We've put new cylinder sleeves in the block and we've reinforced the stock cylinder head in two places to add strength to it. We've also done some special machining to the cylinder head to allow more air to flow in and out of the motor.