premium gas a bargain
 

with gas prices here of 4.57 for regular and 4.77 for premium, that is a difference of 4.5 % since premium will allow more advanced timing without pinging, will mpg gains be bigger than 5%? if so, premium can be a bargain.

Last fill here yesterday, it was $3.789 for regular.

I use the cheapest gas I can find, usually from one station.

Wife uses regular even though her Murano recommends premium.

She averages 21.8 MPG rated 20-24 I think.


I do find it humerous you consider gas a bargain at that price.


Only one way to prove which is the better choice, try both with precise fuel mileage maeausrements. Cars designed to use regular will probably not do better. That being said on my 06 Corolla the best tank I ever got was 39.5 MPG, all highway on mid range fuel without alcohol.

regards
gary

it all depends on the car. some will get worse with the higher octanes.

okay, I should of been more specific, on vehicles that you can adjust the timing, more octane allows for more advanced timing, my question, will the extra .20 cents per gallon pay for itself , and no ,I don't consider these gas prices a bargain, but premium seems a bargain compared to the price of regular IF it will increase gas mileage, I wish I could find gas for under 4.00

To do a comparison we need tank mpgs for 87 and premium. My 93 Mazda MX6 LS V6 needed premium, but it ran 87 fine! I get 21 mpg avg on it on 87, never tried premium or hypermiling on it!

While this wiki requires more sources for verification, it follows my understanding of octane and it's effects on gasoline engines https://en.wikipedia.org/wiki/Octane_rating

IF my understanding is correct, then the short answer to your question is no, and the long answer is yes with a but. So, short answer "no" first. For most compact cars higher octane gas will not give you better gas mileage. In fact, it may even produce lower mpg's because your engine is not able to produce the appropriate amount of total compression necessary to be able to completely burn the higher octane gas regardless of advancing the timing. Basically you lose out on mpg's and $$. Longer answer yes with a "but" (although it's not really longer:) ) Now should you be asking about towing heavy loads, than yes, in some cases higher octane fuels are appropriate as load and heat tend to run hand in hand.

So unless you are driving a full sized pickup and are towing heavy loads, save your money and run the gas the manufacture designed it to run on.

N

My 98 Honda Prelude calls for premium but the manual says you can use regular if premium is not available. I am getting 28 mpg with regular.Havent ran a whole tank of premium through it yet.Will post results. I have read in other forums that the O2 sensors will be damaged with regular.

on my motorcycle I advanced the timing, filled up with premium. went from 45 to 47 mpg, a 4.5% gain .since the premium costs 4.5% more, it was a wash

My cressida it pays off. my truck gets better mpg with advanced timing. if premium allows me more advance and the trend continues (haven't had a chance to put premium in and test yet), absolutely it's worth it. That doesn't mean your car or any other will work the same

the easiest way to compare this (rather than % change in price vs % change in FE) is to open excel or your preferred spreadsheet program. I laid it out gas price on the left in cents (400 for $4.00) 100 in the first cell, increasing as you go down the cells and put MPG on top low on the left, high on the right. for the body, divide the $$ per gallon by the miles per gallon. the gallons cancel out and you get $$ per mile in cents. obviously, you want lower cents per mile. then just look up your total mpg and what you paid for it and see what you spent per mile.

the difference is in half a cent per mile often but it adds up. if you can quiet that voice screaming about how much more you just paid for a tank of gas and realise you went enough further to be worth it, kudos.

I went from 85 to 87 octane and my MPG increased 10%. It cost $1 more per fillup to use mid-grade, but I gained another 50 miles on the tank. I actually save $3 a tank full by spending the extra $1 for 87 mid-grade. I won't go back to the cheapest gas, because it costs too much to use it!

FWIW gas octane mixes close to linearly (it's not totally linear, but it is close). So if you want 89 octane, you also have the option of putting in 1/3 of the 93 octane and 2/3 of the 87 octane. And with many stations/pumps, mixing your own octane grade (from a combo of the cheap grade and the high grade) is often cheaper to do than just to pump the mid-grade.

NOTE: If you are going to mix your own grade, always put the high grade stuff in first. The reason is that the gas doesn't totally mix right away, and so you generally want the higher grade stuff in first, so if/when you get unmixed gas you get the higher grade stuff.

Manufacturer recommends 91 octane.We have 87,89 & 93 octane around here.I never thought about mixing. I might try it and see how the Lude runs.It runs a lot better with 93 but a mixture of 91 might work just has well.

Running premium in the Prelude has not gotten me any better gas mileage. I also added the Bosch Platinum + 4 spark plugs and it hasnt helped any either. Fixing to change the wires,distributor cap and rotor. Maybe there will be a change after I have done that. One of the guys at work says I am wasting my money doing this because any added gas mileage will not pay for the added parts. But the car has almost 140,000 miles on it and needs the maintenance whether it helps the mileage or not.
I sure had hoped the premium would get it a little better gas mileage but you cant get everything.

if your engine is not pinging, premium will not help mpg. if ,however, it allows you to advance timing, then it might help.the difference between 89 and 93 octane is so little, it probably won't allow enough timing change to make a difference.

The mpg is 10%+ higher in my '97 RL on premium than on regular and premium is only about 7% more expensive here, so it makes sense. The big thing that many people with FlexFuel cars aren't keying in on is that E85 is only $2.97 while regular (E10) is $3.87. That's a 30% difference, and most FF cars only lose 20-25% mileage on E85. In my '94 Vigor it's definitely more cost effective to use E85.

I was running 85 (we have it here in the Denver area) and switching to 87 - mid-grade, I got enough MPG increase to warrant paying extra for better economy. I figured I was saving $3.00 a tank by using 87 vice 85. I saw a 10% increase in MPG over at least 4 tanks. I am currently experimenting with my first partial tank of 91.

I wish E85 was more readily available here. Seems that the only public fuel stations here in the DC area that sell E85 are inside the DC beltway (and even then there are only a small handfull) I avoid that area like the plague. One would think that the huge stations here that specialize in low cost fuel like Sheetz or Wawa would be all over it. Their stations are always in high traffic areas and they always sell a high volume of fuel.

-Jay

I used to live out west, and they would frequently have 86 as the regular, 85 in some places.

"Back East" 87 is regular, 89 is mid (aka Plus), and 91 is premium (although Sunoco stations have FOUR grades, 87,89,91,93).

I've never tried anything but 87 in my car.

LOL, Sunoco... If you remember years back Sunoco used to have that dial on the side of the pump where you were supposed to select which additives you wanted in the gas. Grandpa always said that it didn't do anything but make you feel like you're doing something when you turned it.

-Jay