Wednesday, August 01, 2007

Today's SciAm Moment

Another excerpt from the July 2007 issue of Scientific American, this time from the Fact or Fiction? column (yes, guess what I've been reading on the bus to work):

Most modern cars, however, are designed to employ a specific compression ratio, a measure of how much room is available to the fuel when the piston is at the bottom and the top of the cylinder. This compression ratio—somewhere in the neighborhood of eight to one—tolerates lower octane fuels (such as regular gasoline, good old 87 octane) without knocking. "The compression ratio is fixed by the designer of the engine," Green says. "The regular fuel will burn properly and the premium fuel will burn properly and therefore there is no reason you should pay the extra money."...

...Such high compression ratios—and the premium fuels that go with them—could be turned to efficiency, rather than speed, Green notes, especially if put into the engines of lighter cars like his Honda Civic. Other automotive fuels, such as ethanol, can also offer high octane ratings, allowing oil companies to use more volatile gasoline in such blends. But for standard cars on the road today, purchasing premium gasoline is simply paying a premium for a fuel that delivers no added benefits. "If you think you need it," Green says, "you're being very eccentric."

Labels: ,

2 Comments:

At 20 October, 2015 20:56, Anonymous Anonymous said...

polo ralph lauren, oakley pas cher, nike roshe, vanessa bruno, lululemon outlet online, nike free pas cher, abercrombie and fitch, louboutin, nike tn, nike free, true religion outlet, longchamp, sac guess, air max pas cher, true religion outlet, coach factory outlet, hollister, nike blazer, new balance pas cher, sac longchamp pas cher, coach outlet, kate spade handbags, timberland, air max, mulberry, coach outlet store online, true religion jeans, ralph lauren, north face, coach purses, vans pas cher, ray ban pas cher, nike air force, michael kors, michael kors outlet, polo lacoste, air max, nike roshe run pas cher, sac hermes, converse pas cher, michael kors uk, north face, ray ban sunglasses, hollister, michael kors pas cher, nike air max, true religion jeans, hogan outlet, air jordan, sac burberry

 
At 20 October, 2015 20:58, Anonymous Anonymous said...

nike trainers, baseball bats, valentino shoes, vans shoes, north face outlet, celine handbags, louboutin, oakley, asics running shoes, wedding dresses, babyliss pro, abercrombie, giuseppe zanotti, hollister, timberland boots, new balance shoes, vans, air max, mcm handbags, lululemon outlet, air max, jimmy choo outlet, instyler, reebok outlet, gucci, p90x, bottega veneta, soccer jerseys, birkin bag, north face jackets, nfl jerseys, ghd, insanity workout, nike roshe run, ray ban, mont blanc, converse shoes, abercrombie and fitch, soccer shoes, converse, nike huaraches, iphone cases, herve leger, mac cosmetics, beats by dre, longchamp, chi flat iron, hollister clothing store, ralph lauren, ferragamo shoes, burberry outlet, air max

 

Post a Comment

Send Haloscan trackback ping

<< Home

Academics Blog Top Sites