The Little Shop that Could - Extrude Hone pumps an additional 5 to 10 hp inFord's Contour SVT

Editor's note: Last month, Ward's named its 10 Best Engines of 1998 and announced the winners at the North American International Auto Show in Detroit. While BMW, Ford, General Motors, Mazda, Mercedes-Benz, Nissan, Toyota and Volkswagen get the credit - and the awards - a number of suppliers played key roles in the engines' success. Here's a look at three.Larry Rhoades refers to it as an "interesting

Tom Murphy, Managing Editor

February 1, 1998

3 Min Read
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Editor's note: Last month, Ward's named its 10 Best Engines of 1998 and announced the winners at the North American International Auto Show in Detroit. While BMW, Ford, General Motors, Mazda, Mercedes-Benz, Nissan, Toyota and Volkswagen get the credit - and the awards - a number of suppliers played key roles in the engines' success. Here's a look at three.

Larry Rhoades refers to it as an "interesting alignment of the planets" that gave his little-known company a key role in building the Ford SVT 2.5L V-6, selected as one of Ward's 10 Best Engines of 1998 (see WAW Jan.'98, p.25).

Mr. Rhoades is president of Extrude Hone Corp. of Irwin, PA, which has carved out a niche by using an abrasive putty to achieve ultrasmooth surfaces inside race car engines, aircraft turbine engines, diesel equipment and even for medical products.

For race-car engines, the putty, which has the consistency of wet cement or cookie dough, is pumped through air intake components to remove any imperfections in the casting. The result is better air flow and, of course, more power - as much as 30 hp in some applications. It's one of those little secrets the racing crowd loves.

The company's customer base is diverse, from NASCAR and European Formula 1 to street machines. The first production vehicle to use Extrude Hone's abrasive flow process was the Renault Clio Williams, a sporty version of the French compact car.

Two years ago, the company began a research project with the U.S. Department of Commerce aimed at using its abrasive flow process to customize air intake components based on where a vehicle is to be driven. In a high-altitude region like Colorado, thin air can leave an engine cylinder with an improperly lean mix of air versus fuel.

"You need a more generous air flow to mix with the fuel so you have complete combustion," says Mr. Rhoades. "Without it, the combustion is incomplete, and the fuel is going out the exhaust pipe. Our idea is to tune the air flow for geographic calibration reasons . . . and to balance the flow so all cylinders get uniform flow resistance."

Mr. Rhoades says tuned air flow and high-precision combustion chambers could improve fuel efficiency by 6%.

Ford Motor Co. and General Motors Corp. had joined the research project, and Ford offered some engine components for Extrude Hone to develop its theory. Ford was so impressed that it hired Extrude Hone to work on its new SVT 2.5L engine.

The abrasive is pumped through the upper intake manifold and the secondary intake port of the cylinder head. The castings are shipped to Extrude Hone's facility in Irwin for the treatment.

It represents the company's first job on a production vehicle in the United States.

Curt Hill, Ford's engineering supervisor of Duratec engine programs, says Extrude Hone's process adds between 5 and 10 hp.

"We never could have gotten to 195 hp without it," he says. "This process equalizes the air flow to all cylinders, reduces the variation from cylinder to cylinder, and it increases the air flow."

Despite the great potential for extrude honing, Mr. Hill says cost pressures may limit its use on larger engine projects. Ford has said its target is to sell 5,000 Contour SVTs a year.

"There's an incremental cost associated with it," Mr. Hill says, "but it wouldn't surprise me to see it in another SVT engine."

Mr. Rhoades says Extrude Hone charges between $2 and $10 for each additional hp achieved by using the process. "Our goal is to be at $1 per additional horsepower," he says, "and we're moving dramatically toward this."

If his company can get the cost down, Mr. Rhoades is convinced Extrude Hone's business will take off.

"Our overall volume on the SVT is not huge, but strategically it's very important," he says.

With annual sales of about $30 million, Extrude Hone is small by contemporary supplier standards. The company has 250 employees at operations in Los Angeles, Ireland, Japan, England, France, Germany and China. The company was founded 30 years ago by Mr. Rhoades' father and two partners. o

About the Author

Tom Murphy

Managing Editor, Informa/WardsAuto

Tom Murphy test drives cars throughout the year and focuses on powertrain and interior technology. He leads selection of the Wards 10 Best Engines, Wards 10 Best Interiors and Wards 10 Best UX competitions. Tom grills year-round, never leaves home without a guitar pick and aspires to own a Jaguar E-Type someday.

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