BUFFALO -- Toyota's West Virginia plant has been named the mainly productive engine maker in North America for the fifth uninterrupted year by a national auto industry analyst.

Toyota Motor Manufacturing, West Virginia, Inc. topped the rankings in the meeting of both four cylinder and six cylinder engines, Harbor Consulting of Troy, Mich., said in its 2006 Harbor Report.

In 2005, workers at the Buffalo plant formed four-cylinder engines in an average 1.82 hours and six-cylinder engines in a standard 2.95 hours, the report said.

"What the workers at our Buffalo plant have done is simply unheard of," U.S. Sen. Jay Rockefeller said in a prepared statement. "They have turned the production of automobile engines into an art form."

The plant manufactures four-cylinder engines for the Corolla, Matrix and Pontiac Vibe; six-cylinder engines for the Sienna and Lexus RX 330; and five-speed transmissions for the Camry, Sienna and RX 330.

"Toyota remains the benchmark in engine productivity," said Michelle Hill, director of North American benchmarking for Harbor Consulting.