7th Feb 2011, 08:19
"I can't fathom why a car's engine computer would make it run LESS efficiently and use MORE fuel with premium."
No one said it would run less efficiently. There is an optimum range in which the computer will keep the engine running at, no matter which fuel type you are using. I used to be on the premium fuel train too with my old 5.0 Mustang, but I switched to regular, at the recommendation of a few different mechanics who said I was wasting money, and it really never made a difference. I was going just as fast off the line, and still not losing many races. I also was getting around 27 mpg on highway trips with regular unleaded, and this was in the 80's with a V8.
I wasted a lot of money needlessly thinking I was able to go so much faster, but it was just that... wasted money. You can argue this back and forth all day long, but the truth is it only costs you more money, not me, so I don't really care. I learned the lesson 20 years ago. I refuse to buy any car that requires premium, and I certainly won't ever be using it in a car that doesn't. But hey, you are making the oil companies happy... I guess that is something!
6th Feb 2011, 13:07
Because your wife said so, eh? Must be legit. Also, see above, two people (or one person with a double post?) explained the whole compression deal already. As a chemical engineering student and amateur mechanic, I can say they make sense.
"Wow. Either you have a HUGE gas tank or gas prices vary a LOT between regular and premium where you drive. It costs me $3.60 more to fill up with premium than with regular."
It's a bit of both. And that's a total of $15 for both tanks, not $15 extra per tank.