ETC, ETC . . . Delphi electronic throttle control packaged for LS1

Just ask the engineers at Chevrolet how tough it was to package a hulking 5.7L V-8 engine inside the relatively small front end of the new Corvette, and you're likely to get an earful.

So when electronic throttle control became a viable option to allow for easier packaging as well as provide responsive acceleration, the engineers just had to have it.

The LS1 is the first passenger car engine from General Motors Corp. equipped with electronic throttle control (ETC), supplied by Delphi Energy & Engine Management Systems in Flint, MI.

ETC, which is beginning to appear on high-end vehicles, replaces the cables connecting the throttle to the accelerator pedal.

On the LS1, ETC also integrates cruise control, brake torque management and traction control into a single controller. The system reduces weight and cost and improves emissions and fuel economy.

"Underhood space was at a premium on the Corvette, so packaging was one of the drivers behind this," says Steve Aikman, staff engineer and program manager for ETC at Delphi Energy.

Bob Gasper, director of supplier quality for GM Powertrain, credits Delphi Energy with a significant contribution to the Corvette. "This was their technology, and they made it happen. From the time the technology was developed it was meant to be part of this car," Mr. Gasper says.

"When you're talking about physically separating the driver from the throttle you have some concern. But in this case I don't think the driver senses the difference," he says.

He says Delphi Energy was among numerous powertrain suppliers contributing to Corvette's heritage as a showcase for leading-edge technology. "Everyone understood how important this product was to suppliers because it was the first generation of a new version of engine, and there would be a lot more of them to follow in trucks."

Although the LS1 engine block is aluminum, similar iron-block versions will appear on GM's new full-size pickups and sport/utility vehicles derived from the GMT800 pickup platform.

The cylinder heads for the LS1 also are aluminum and are supplied by Saginaw Metal Casting Operations, an internal supplier to GM Powertrain.

Plant employees were more than a little concerned when GM served noticed in 1993 that Saginaw Metal Casting would no longer be making iron cylinder heads because of excess capacity. So a major push was made to convert the plant for aluminum production.

Today, the plant is busy cranking out cylinder heads, not only for LS1 but also for Camaro and Firebird and, later this year, the GMT800 truck engines.