808SE

So anyone here notice a major change in performance with higher octane gas? I did a search but didn't come up with what I wanted.

I recently was running on fumes and since I couldn't go the my regular gas station I went to a nearby Chevron. I usually fill up with 89, but decided to try a 92 octane with techron. So all of a sudden my 92 VE is running smoother. Now I know this could be my imagination, but I'm also getting like 25% more mileage. I'm already at my usual milage per tank and I have a quarter tank to go.



This ever happen to anyone else?

Thanks in advance.

vmok

Could be the Techron in the Chevron gas as well. I only use Chevron in all my cars because of that. Apparently, the stuff really works, and if you try calling most of the auto manufactueres, they recommend Chevron and usually another brand like Shell or 76, but the common factor is always Chevron. There's an article that tells how the Big 3 use only Chevron in the cars that they submit for emissions testing as well.

Also, I believe the owners manual recommends premium fuel in our cars, so the improved performance wouldn't surprise me.

-V

matt92gxe

i also use chevron w/ techron 93 octane and my car runs smooth as silk!

jwtarbaj

OK Car & Driver just did a story about this in the last issue (it has a Ferrari and Aston Martin on the front). They did a test of cars that require reg (87 octane) and cars that require premium (>90 octane) per the manufacturer. It shows that there is more power to be found with SOME vehicles that had premium but only required reg. BUT some cars actually lost power (Honda Accord V6). All in all it looks like for the money the higher octane gas is not worth it unless you advance your timing.

John
91 Max SE
5-spd SMC STS, PR CAI, Cattman Y, Cortesy FSTB, Tokico Blues, Foglight rewire, GTS Blackouts, DARK Tint, peeling stock rims :-(

vmok

The article notes that the car must be able to take advantage of the higher octane detonation resistant fuel. It also noted that driving most modern cars that recommend premium fuel, you wouldn't know that you were loosing power and performance because vehicles nowadays run so well even on regular fuel, albiet less efficiently. The ECU can look for problems while the vehicle is running and compensate. If you look in the owners manual, it recommends 91 octane fuel for both the 3rd gen and 4th gen maximas, but notes that using normal fuel will not hurt the vehicle. Items such as knock sensors will automatically retard timing when knock is sensed so no engine damage will occur. However, running efficiency as well as mileage and power may suffer.

-V

http://forums.maxima.org/showthread....5&pagenumber=2

that's a thread on premium fuel...

jwtarbaj

Just as a note VG Maximas require regular 87 octane gas not premium 91 octane. Also the Maxima's ECCS engine management does have the capability of adjusting for higher octane gas.

vmok

The last page (what would be page 10-4) in my 1990 Maxima SE's owner's manual states:

"Recomended fuel: Unleaded gasoline, at least 87 AKI ... premium unleaded gasoline of at least 91 AKI number (RON96) is recomended."

It states something to the similar effect for my 97 SE, and that if premium fuel is not available, regular 87 octane will work fine.

I guess you can construe from that statement that any car today with a knock sensor will work fine with regular 87 octane fuel with less efficiency. I believe in the end, it'll come out the same in terms of $$$. You pay less for gas, but get lower gas mileage and less power, making you press on the gas more. SO the lower cost of lesser fuel is offset by the lower mile per gallons due to reduced efficiency.

-V

Pit5Bull

…according to an old (don't ask me how I ended up reading this article lately) R&T 'Tech Tidbits' topic titled "Curious about additives and octane?" (July 97)

This article discusses many readers' concerns about the type of gasoline they use in their rides. To make a long story short, the author, Dennis Simanaitis, responded to the following question:

Does premium gasoline along offer better performance and mpg than regular?

"Before my recent chats, I would have said 'No,' but now I'll refine this to 'It depends.' I've learned that premiums traditionally have had a slightly higher heating value than regular gasolines, and thus might offer slightly more power or mpg. It's less than 1 percent, though, not enough to offset a premium's higher price."

I also didn't know that octane refers to the resistance of the gasoline versus detonation when it reaches the cylinder & spark plugs - the learning curver continues!!!

I liken this analogy to this whole octane thing - it's a whole lot like buying toilet paper at the grocery store. There's a whole lot of brands, with all their little comfort pillows and stuff. But, depending on what your a$$ has gotten used to, you're still just tossing $$$ down the toilet. You decide how quickly you want to empty your pockets!

I have a VG, so regular unleaded it is !

peace2u

scott92282

iTrader: (2)

I only use premium Shell. When I first got my car, I used regular, and noticed that the gas was diminishing as quickly as my old POS (which had a smaller gas tank), so the mpg was horrible. I upgraded to premium, and the mpg instantaneously increased. I've tried several brands of gas, and the only one, so far, that has not hesitated at 4000 rpm is Shell. On a good run of gas I get anywhere from 26 to 28 mpg in my 93 SE. I don't tend to drive like a grandmother going to church either, I drive from Annapolis, MD to Baltimore, MD several times a week (beltway traffic). Some of this is stop-and-go if there is a lot of traffic. Otherwise, I am going about 65 to 80 mph the whole way (about 50 miles one-way). I must say that I am very pleased with the performance of Shell premium.