The K&N goes in

25.7 MPG. That's what my wife Robin has been averaging in her 1996 Honda Accord EX wagon. Quick tangent: That right there is one of the main reasons I like cars so much better than SUVs. We've test-driven SUVs with less cargo space than the Accord wagon that struggled to break 20 MPG when lightly loaded. Consider all that the wagon has working against it: It's always loaded with at least a couple hundred pounds of cargo, it has an automatic transmission, Robin's a leadfoot and lots of her driving is in the hills. Yet she's still averaging almost 26 MPG. As Scotty would say, you canna change the laws of physics, Jim.

So yesterday I pulled out the paper air filter and swapped in the K&N. Interestingly, the K&N seems to be a bit wider than the paper filter I pulled out; it forms a solid seal between itself and the edges of the filter housing. That's good, because I've seen traces of dust at the top of the housing which lead me to believe that air has been seeping in upstream of the paper filter. Now, the paper filter wasn't all that dirty, so I don't know if we'll see a dramatic increase. Not to start the whole K&N argument again, but K&N doesn't promise better gas mileage (though many customers report it); they say the filter stays cleaner longer. And because you wash it and re-use it, they say, it saves money. The K&N is about twice the cost of a paper filter for the Accord, so even with the cost of the cleaning kit, it'd pay for itself by the third change -- 'cept in the 53,000 or so miles we've had the wagon, I've changed the filter once or twice, not 3 to 4 times as per the maintenance schedule. Goodness knows how much that cost me in lost fuel economy.

In other news: Tonight I'm taking our other Accord (a '93 sedan) on a second run through my super-secret fuel economy test loop, again to get a baseline MPG figure. Once that's done, I'll be trying out my top ten fuel saving tips to see how much savings they actually yield. -- Aaron Gold