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You've probably heard stories about the emissions of today's cars being cleaner than lawn equipment, about modern cars actually cleaning the air and about the pre-emissions-control era when birds fell from the stinking sky. So have we. We're all about busting myths, so we concocted an investigation to find the truth. Forget about the birds, but those other rumors, well, we've got them covered.
Big, Small and Handheld
Early on, we decided to go big. We'd run this emissions test at a real-deal emissions lab rather than a smog check station or asking Magrath to inhale at the tailpipes and offer commentary on their bouquets.
It would have been easy to load this test in favor of the vehicles by hand-picking the cleanest combustion-powered vehicle we could find. No, only the biggest, baddest truck will do, and they don't come much bigger or badder than the 2011 Ford F-150 SVT Raptor Crew Cab. Acting as a counterweight in perception to this pickup is our long-term 2012 Fiat 500.
The vehicles are absolutely poles apart. The Raptor packs a 411-horsepower 6.2-liter V8, weighs more than 6,200 pounds and has the aerodynamics of Mount Rushmore. The dollop-size Fiat weighs a mere 2,350 pounds and has a 1.4-liter four that generates less than one-fourth the amount of power as the Raptor. They couldn't be more different, and capturing extremes is the idea.
Like you, we made a trip Home Depot to buy a leaf blower. And like all trips to Home Depot, we lost 3 hours and bought more than we intended. In this case we ended up with two leaf blowers — a two-stroke backpack-style job and a handheld four-stroke unit. The two-stroke leaf blower in this test is an Echo PB-500T, a model that sits in the middle of the manufacturer's range of backpack-style offerings. It's powered by a 50.8cc two-stroke air-cooled single-cylinder engine. The Ryobi is a RY09440 model that brings a 30cc four-stroke engine. Yes, we're pitting a 6,210cc truck against a 30cc leaf blower.
There were fewer hydrocarbons in the Raptor's exhaust than in the air it — and we — breathed.
Two-stroke engines have high power density, making them the engine of choice among commercial and prosumer-grade leaf blowers, but they emit more pollutants than four-strokes. The four-stroke leaf blower in this test is the Fiat to the two-stroke's Raptor. That was the idea, anyway.
2011 Ford Raptor 0.005 0.005 0.276
2012 Fiat 500 0.016 0.010 0.192
Ryobi 4-stroke leaf blower 0.182 0.031 3.714
Echo 2-stroke leaf blower 1.495 0.010 6.445
Distilling the above results, the four-stroke Ryobi leaf blower kicked out 6.8 times more NOx, 13.5 times more CO and more than 36 times more NMHC than the Raptor.
The two-stroke leaf blower was worse still, generating 23 times the NOx and nearly 300 times more NMHC than the crew cab pickup. Let's put that in perspective. To equal the hydrocarbon emissions of about a half-hour of yard work with this two-stroke leaf blower, you'd have to drive a Raptor for 3,887 miles, or the distance from Northern Texas to Anchorage, Alaska.
Clearly, engine displacement plays little part in the concentrations of these pollutants. Consider that the Fiat 500 produced more than double the NOx and more than three times the hydrocarbons of the truck. A close look at the vehicles' underhood emissions labels sheds further light — the Fiat 500 is classed as LEV-II, whereas the Raptor in California trim is ULEV-II. The Raptor's emissions control equipment is simply more capable. It's only in the production of carbon dioxide (CO2) — not yet directly regulated by EPA or CARB — where the Raptor is the higher emitter.
Drive a Raptor. Clean the Air
Remember that crazy-expensive lab equipment that measures exhaust emissions? It also measures the emissions makeup of the ambient air that the vehicles draw in through their intake tracts. This is important because, well, what if your emissions lab was located next to a natural gas vent? Only by measuring what goes into and out of the vehicle and comparing the differences can the vehicle's contribution to emissions be accurately assessed.
Here's why you should care. When the Raptor (and the Fiat) was running Phase 2 of its tests on the dyno, it was cleaning the air of hydrocarbons. Yes, there were actually fewer hydrocarbons in the Raptor's exhaust than in the air it — and we — breathed. In the Raptor's case, the ambient air contained 2.821 ppm of total hydrocarbons, and the amount of total hydrocarbons coming out the Raptor's tailpipe measured 2.639 ppm.
Edmund's Inside Line