Familiar Horsepower Rating No Longer Standard
Small-Engine Makers May Cite Torque, Cubic Centimeters or Nothing at All

By Rick Barrett
Milwaukee Journal Sentinel
Saturday, February 16, 2008

For buyers of lawn and garden equipment this spring, a familiar old term -- horsepower -- will be missing from many engines.

Blame it on lawyers, or on engine makers who might have fudged the numbers, but horsepower is no longer the gold standard for small gasoline engines.

Sears, for example, now advertises some lawn mowers rated by horsepower, others by torque and still others by cubic centimeters. Some mowers have no designation at all.

"Unfortunately, we are not giving consumers the answers they want," said Bill Rotter, a Milwaukee-area hardware store owner.

There's no longer a horsepower rating for many Briggs & Stratton engines. Last year, Briggs chose torque as its rating system for push mowers, snow throwers, pressure washers and generators.

In basic terms, torque is a measure of the force needed to turn something, like a wrench or a lawn mower blade.

"We think it's a better measurement of a mower's ability to cut grass," said Rick Zeckmeister, North American consumer marketing director at Briggs, the world's largest manufacturer of small gasoline engines.

Horsepower, on the other hand, evolved from a measure of the rate at which a horse could pull coal up a mineshaft into a more technical measurement related to watts. Although most people don't know its technical meaning, many have found horsepower useful in comparing the power of engines.

So now consumers may face confusion over how torque relates to horsepower. There isn't a practical conversion chart because torque and horsepower measure two things.

"Torque doesn't mean much to the consumer," Rotter said. "And it's more complicated for us because it's almost impossible to try and explain what gross torque means" to someone buying a lawn mower.

Rotter said he wouldn't be surprised if, down the road, engine manufacturers return to horsepower ratings.

The shift away from horsepower ratings came after a lawsuit in Illinois claiming that engine manufacturers were overstating the horsepower of lawn mower engines.

In some cases, the lawsuit alleged, identical engines were labeled with different horsepower ratings, leading consumers to believe they were getting more power by purchasing more expensive models.

Briggs advertised one engine as having 6.75 horsepower and yet told the Environmental Protection Agency the same engine had 3.6 horsepower, an 88 percent overstatement, according to the lawsuit.

At least since 1997, the engine manufacturers Briggs, Tecumseh, Kohler, Toro and Kawasaki have reported horsepower ratings to the EPA that were significantly lower than the ratings advertised to the public, the lawsuit said.

For Briggs, it wasn't an attempt to mislead anyone, according to Thomas R. Savage, a senior vice president at the company.

There are different testing protocols for the EPA than for the general public, Savage said. The EPA ratings are based on a "composite" of test results at different engine loads, while results for the public are based on an engine's full-power capabilities.

An Illinois judge dismissed the suit in March, but it may resurface.

"It's still not totally resolved because the judge did not tell us what portions of the suit he dismissed with prejudice or not. So in effect, it allows the lawyers to come back," said James E. Brenn, Briggs's chief financial officer.

Over the years, manufacturers in the intensely competitive small-engine business have used horsepower ratings as a marketing tool.

"Horsepower sells," said Jeff Hebbard, a vice president at Ariens, a manufacturer of lawn tractors and other outdoor power equipment in Wisconsin. "It doesn't always sell for the right reasons, but it does sell."

The horsepower race sounds like what has occurred with electric motors, where power claims have been embellished, said Kevin Brady, a Minneapolis lawyer and engineer not affiliated with the horsepower lawsuit.

"You can exaggerate a bit and not get in trouble," Brady said. "It's called puffing."

In reporting to the EPA, engine manufacturers have leeway to fudge horsepower ratings by about 15 percent.

Sometimes, the same engine is advertised as having different horsepower ratings depending on how it's sold.

"There are slight adjustments that get them there, but it's the same engine," Hebbard said.

Ariens buys engines from Briggs, Kohler, Honda and other manufacturers.

It has been challenging for the engine makers to find a rating system that works, said Dan Ariens, the company president.

"Americans are very familiar with horsepower. It's a number they kind of understand," Ariens said.

It's uncertain which power standard the small-engine manufacturers will settle on, if they agree at all.

"Some guys like to have cubic centimeters as their standard, some like torque, and some like horsepower," said Savage of Briggs. "I don't know if there will be a one-size-fits-all solution."

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