This again...
Some people REALLY shouldn't drive cars they can't afford fuel for.
Why do do people step over a dollar to save a dime?
On average premium is 10 to 15 cents more expensive than regular.
Lets have us a little math session.
We'll use rounded numbers for the slower people.
Say that your car will average 20 miles per gallon over the span of 100,000 miles. That gives us 5000 gallons of fuel used for that 100K miles.
At $3 a gallon for regular unleaded, that comes to $15K in fuel.
At $3.15 a gallon for premium, that comes out to $15,750.
We take the difference of the two, and we end up with $750 extra over the course of 100K miles.
At an average of 15K miles, a year, that breaks down to to 6.67 years to put 100K miles on that car.
We take this extra $750 and we divide that by 6.67, and we end up with 112.47 extra dollars a year in fuel costs.
Now you tell me, is this $113 (rounded up) worth upwards of what, $2000-$3000 dollars to replace your engine because it went south due to constant detonation?
There is a reason why these cars require premium. Otherwise FORD would have recommended regular unleaded in these cars. Will your motor absolutely bomb if you constantly run regular in it? May so, maybe not. But think of it as an insurance policy.
Yes, the car can adjust to regular unleaded. But you also won't get the fuel economy the car would get if you were to run the required premium fuel. Lets not talk about what happens when you put your foot into it. We've already discussed how much an engine can cost to replace after you bomb it.
A lot of people seem to want performance, but don't want to pay for it. They abuse their cars, and when they break, they cry out about what a piece of crap the car is, because all this stuff keep breaking. Well DUH!
So you go ahead and run regular unleaded in your car. When the engine blows up and you can't afford to replace the motor because you didn't want to spend a measely extra $3 at the pump because you had to get your $2 twelve ounce bottle of Evian and then you junk it, there will be more junk yard LS's for other people to pull parts off of.
IMHO, if you can't afford the gas it calls for, you really have no business owning it.
I buy 100 Octane at lower elevations. Why? Because that's what the motor is tuned for. Personally, I don't like replacing 70K dollar motors because I skimped on a few dimes (let alone the extra $3.75 per gallon for 100 test) at the gas station. Now, an LS motor is obviously nowhere near 70 grand, but you get the idea.
This is what it costs me to fill up 3/4 of a tank (I don't like running a car below 1/4 or so) every few days.
Am I bitching? No. I know what I was getting into when I bought the car. I didn't buy the car and then bitch and moan about how expensive it is to run.