Whenever we go to a gas station there always “plus” and/or “premium” gas ten to twenty cents more expensive than regular. Does anybody ever buy that gas?
Yes, I drive a Volvo C30, which can operate on regular, but gets better performance on Premium. Mostly it’s high end sports cars that use Premium, as well as dudes that don’t know better.
Yes. My parents have always only bought Premium for their cars. (Various Nissans & Toyotas.)
They are very likely wasting their money. Buy only the grade recommended int he manual.
First part: Maybe. Grandpa had a High Compression Ratio V-6 in his Acura that needed premium
Second part: Definitely. If a car does not require premium, it may not have the calibration to make use of the added knock resistance that you get out of premium. The added potential would not be used.
That said, Modern cars that require premium will have the ability to run on regular, albiet with a significant reduction in performance. They have to account for varying qualities of gas and the slight possibility of not having premium available.
I have a Subaru STi. It requires premium. I ran regular gas through it when premium was cresting $4.50 a gallon. I just stayed out of the boost while doing so. Both it and I sure were happy when fuel prices dropped and my income went back up.
Yes, I used to buy premium when I had a VW Passat turbo which required premium gas. However, buying premium for a car that doesn’t require it is just wasting money. I don’t buy size 12 running shoes for my size 10 feet and think they’ll help me run faster!
Yes. My YZF-R1 is placarded for 92 octane, and my '66 MGB runs better on Premium. (I could probably use mid-grade in the MG, since it doesn’t get very hot up here.)
I’m seeing a growing number of gas stations line up the premium hose and nozzle first (to the farthest left), followed by the plus and regular on the far right. The only reason I think gas stations are doing it is to take advantage of gas buyers who aren’t paying attention, and just reach for the first nozzle.
They nailed me with that trick two weeks ago. Won’t get me twice, however.
I buy premium gas in storage cans for my generator, chain saws and other small motors. I was told by a guy who sells that sort of thing that what gas loses in long term storage is octane number, so if you think you might store the gas for weeks or months, buy higher octane to start with.
In the case of a motor vehicle, always run the gas that the owner’s manual recommends. Usually this is regular, except for some high performance engines.
Can anyone validate this? I’m getting ready to pretty much put a car away for the winter (I still plan to start and run every couple of weeks) and want to know if this would be good to buy higher octane gas and/or use the gas stabelizers.
I use a gas stabilizer (StaBil) and high octane gas if it’s gas I might be storing for a long time. Have had no problems with gas stored in five gallon cans for up to a year.
As far as validation, all I got is “some good ol’ boy told me…”
High compression engines and turbo charged engines may require premium grade gas. If your car needs it your manual will say so. My car does and says so in the manual and inside the gas filler door. But it is a performance car.
Premium gas is not “better” gas. This is a little complicated so I won’t try to explain it all here. Basically you do not want the fuel to detonate before the spark is given. High octane fuel can be compressed more without blowing up on it’s own. Lower octane fuel may ignite while the piston is still on the up/compression stroke and cause loss of power and over time engine damage (in a high compression engine). If the engine is designed to reach a high compression before the spark is added, it may need high octane gas. There is no benefit if the engine was not designed to use high octane.
The term “Premium” gas is mis-leading. There is nothing better or special about the higher octane gas. To say it is a better grade of gas is wrong. You are not doing your engine a favor by giving it ‘premium’ as a treat if it doesn’t require it, etc. The PCM in your car will adjust for pre-detonation and negate any imagined benefit you may think you get by adding high octane fuel to a regular octane car.
You might even get worse mileage. This is not a case of ‘I only want the best’.
Repeat after me: “Premium gas is not better gas”. Say it, believe it. Put the gas in your car that the engine is designed to use.
You are correct- today, or even since leaded gas went away. But back in the old days, only Premium usually had detergents. That’s why the mechanic for my '61 Impala suggested a tank of Premium (leaded, of course!) once in a while. Note, I did not get the Impala new, I am not that old, it was my HS Grad present, and it was more than 10yrs old.
This may be why “Premium is better” lingers on- not to mention the gas companies trying to sell more of it.
I know nothing about cars, but I think that is why they buy it, because that’s what is recommended.
OK, yes, I just looked at the manual online and it says “For maximum vehicle performance, the use of unleaded premium gasoline is recommended.”
Not sure why the snark was needed.
The word “premium” may have something to do with it, doncha think?
Yes I do everytime. I drive a Volvo s80 with an inline 6 something turbo but it’s required for the car.
The master speaks: http://www.straightdope.com/columns/read/2565/whats-the-difference-between-premium-and-regular-gas
I will add that they mention that ‘higher power’ engines need higher octane gas, what should be said is ‘Higher output per displacement’. You may find a small, 100 hp, 3 cylinder motor needs it because a lower compression 3 cylinder motor would make 78 hp.
FWIW, I seem to recall there IS a SLIGHT improvement in gas milage, but not enough to offset the difference in price. There may be a difference in the detergents used to clean the fuel injectors, but you’ll get just as good a result by changing brands of fuel every few months.
The major fuel brands all source their base stock from the same place. The only difference is the proprietary detergent packages each brand specifies for their fuel. I’ll dig up a cite.
Normally no. I do when I have to cross the Appalachians, because the van will occasionally knock on the hard climbs.
Missed the edit window:
ETA: The Car Talk guys on Premium fuel myths: http://www.cartalk.com/content/features/premium/myths.html
While we’re on the subject. My car’s manual says 91 octane minimum. The closest available to that number is the 93 octane “premium”, so I fill it with that.
A quick question: I was preoccupied Tuesday at the pump and filled the durned thing with 87 octane (regular). Didn’t notice until it was full. Besides driving sedately, is there anything else I should do until this tank is used up? I figure the computer and O2 sensor can probably compensate, as long as I don’t ask the engine for a lot of power.
Any experts care to comment? Is highway driving harmful? For right now I’m babying it so much I’ll probably have to clean bugs off the back window.