Posted on 05/19/2016 3:30:52 PM PDT by littlebird
every time I fill up my car, I suspect all the different octane gasoline are exactly the same, 91 octane. The only difference is what it is called (eg. gold) and the price. Gas company puts in the same octane gas, with a little advertising, gets more money by calling it gold or premium plus. It is all marketing. Unsuspecting driver feels better buying higher price gas for their beloved car. Any one likes to comment.
You signed up today just to post this?
Yes, I will comment that while most gasoline comes from the same refiners, it is the additives - detergents, etc., - that differ from brand to brand.
My wife’s BMW required the highest octane. I didn’t know that. I put in the lowest octane. I complained that there was a delay when I stepped on the gas. She reported that to her BMW salesperson. He immediately knew what the problem was. When I started putting in the highest octane the problem disappeared. The owner’s manual usually gets it right. Most people don’t read it.
IBTZ?
You like to comment, anyone? Who knew!
Welcome to FR.
Build a still at home to test your theory, and distill the different grades. If more octane comes out of the higher-octane grade, the myth will be busted.
You shouldn’t be using anything but regular unless your engine specifically requires a different grade.
I knew someone who had engine troubles with a high-end Porsche, he took it to the dealer and swore that he only put in the premium gas. Dealer told him that was the problem, that the engine was specifically designed for regular gas, and the premium was causing the engine knocks.
The higher the octane, the better the gas mileage. Just an FYI.
I don’t know what gasoline you use, but my car’s computer certainly can tell the difference between regular, mid-grade and premium.
It runs OK on mid grade, GREAT with premium, and kicks, bucks and carries on in most unpleasant ways if someone puts regular into it. And the misbehaviour begins the moment the fuel makes it to the injectors.
I won’t belabour you with how it reacted to stale gas < BG >. Fortunately, I was able to nurse it to a premium pump to make amends...
There are two actual octaves, 87 and 91 (excluding racing fuels, etc). The pumps with multiple blends actually blend the fuel in the pumps. The octane levels are routinely checked by state regulators. You can test the ‘heat’ in the octaves by putting a little of each on the back of your hand, you can actually feel the difference in octane.
Exactly. Here in Denver the grades are 85 87 89. My car needs 87. If I try to operate with 85 it feels like a person trying to go jogging on an empty stomach. Just not enough energy.
I have a 1700cc v-twin motorcycle that requires at least 91 octane.
I remember a B-25 owner/pilot who was on “The History Channel”.
He was explaining why he could not equal a short takeoff which was done by the Doolittle Raiders. He said they had 115 octane aviation gasoline which is not available now.
First and only time I have heard that but I suppose it is true.
What Does Octane Do In Gasoline? Octane Ratings
The octane rating of gasoline essentially tells you how much the air-fuel mixture can be compressed before it will spontaneously ignite. Gasoline with an optimal octane rating performs best in an engine designed to run on that octane level.
I use cheap 85 octane in my 87 octane vehicle and don’t notice difference. The top tier have the most additives. It would be nice for the to take the junk alcohol out. My old tractor requires good 60 octane gas and I can not find any.
Using higher-octane gasoline than your engine is designed to utilize is only wasting your money.
No they are different. If it were not so they’d be taken to court for false advertising. If all the oil companies did it it would e conspiracy to defraud which is a serious crime.
Sorry, but I must disagree. Some engines require the higher octane. Running too low an octane can cause serious engine damage in some higher compression engines. Usually older models. Most of the newer EFI engines can self adjust to lower octane and do fine but some cannot.
There are also detriments to running too high an octane in some engines.
Some manufacturers actually warn owners not to use higher octane fuels.
Not too long ago, I used “premium” 91 octane in all of my motorcycles as a matter of course. Then in a moment of boredom, I read the owners manual and it said to run 87 octane so being more than happy to let the manufacturer take the risk of engine failure, I switched to from 91 to 87. Within two tanks of gas, my power was up and my fuel mileage was up by over 10%. 38-40 mpg to 42-47 mpg. My current bike requires 89 octane and as such gets lower mileage with less horsepower on 87.
So Yes Littlebird, there really is a difference in 87, 89 and 91 octane. And there are reasons for it.
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