grifferjr

not to restate what has already been said, but not only should you not worry about it, you should do it more often to lighten up the burden on the wallet.

i run 91 octane all the time and even 89 every now and again when i know i will be predictably driving a lot on the highway, just cruising. if i know i will be in the city with a lot of acceleration and stuff i will buy the good stuff. in the long run it saves on the gas prices.

oscarmayer00

Don't you guys get it gasoline is gasoline, it's all marketing. A higher octane will give you a little more horse power at the high end so if you race your Z use a 91 or higher octane. Don't worry 87 octane is fine. If it ain't knocking you ain't having a problem.


Can you tell where the gasoline at you local station comes from?

For several reasons, the Energy Information Administration (EIA) cannot definitively say where gasoline at a given station originated:

The name on the service station sign does not tell the whole story. The fact that you purchase gasoline from a given company does not necessarily mean that the gasoline was actually produced by that particular company's refineries. While gasoline is sold at about 176,000 retail outlets across the nation, about one-third of these stations are “unbranded” dealers that may sell gasoline of any brand. The remainder of the outlets are “branded” stations, but may not necessarily be selling gasoline produced at that company's refineries. This is because gasoline from different refineries is often combined for shipment by pipeline, and companies owning service stations in the same area may be purchasing gasoline at the same bulk terminal. In that case, the only difference between the gasoline at station X versus the gasoline at station Y may be the small amount of additives that those companies add to the gasoline before it gets to the pump.

Even if we knew at which company's refinery the gasoline was produced, the source of the crude oil used at that refinery may vary on a day-to-day basis. Most refiners use a mix of crude oils from various domestic and foreign sources. The mix of crude oils can change based on the relative cost and availability of crude oil from different sources.

sentry65

iTrader: (11)

dealers usually put in regular 87 octane in all their cars including the Z....

nbdyfcnsqnc

Oh yeah, I just meant compression as in pressure (how much air/fuel can be compressed into a fixed space), not as in "the engines compression."

Brandon@Forged

The engine uses the knock sensor and will adjust the ignition timing accordingly. No harm done, just less power.

WTF is up with not being able to pump your own fuel though...why is that a law?

Brandon@Forged

Just to clarify, this is partly true. It depends on what octane. There is a member that dyno'd with 93 octane and then 100 octane and gained something like 10+hp from the ECU using the knock sensor and adjusting the ignition timing.

mdracer76

iTrader: (1)

I would return the gas to the station and ask for a refund.

Bran_BranZ33

what if you have a turbo? can you use 91 octane... just wondering!

Brandon@Forged

I would say no unless the engine management doesn't get rid of the knock sensor, in that case, it should be fine.

Balthazar

All of you people saying "use cheap gas to lighten the load on your wallet" seriously need to do some math.

Lets take me, I spend about $30 everytime I goto the pump, which is about once a week, this is by no means an extreme amount and I know just as many people who do as much driving as I know who do more or less driving, so lets take it as the mean amount ok?

Right now gas is $2.11 for the cheap stuff.

So $30 / $2.11 = 14.22 gal.
Now, if you take 14.22 * 2.31 you get $32.85

So 52 weeks * $2.85 = $148.20

So going with the cheap stuff you save $148 a YEAR.
$12.35 a month, $2.85 a week thats a $0.07 raise at your job to cover that.

Its SO insignificant the only REAL savings is in your mind.

$2.85 a week for a cleaner, smoother, better running engine. After spending $30,000 on a car if this seems like a good deal to you, I dunno what to tell you.

nbdyfcnsqnc

^ Totally!


>> The engine uses the knock sensor and will adjust the ignition timing accordingly. No harm done, just less power.

Doesn't it adjust by detecting the vibration of knocking? If so, how does it adjust BACK?


>> WTF is up with not being able to pump your own fuel though...why is that a law?

Tyranny by democracy.

tabrizio

iTrader: (1)

Don't stress too much..wont hurt you in long run but look out for knocking
Read this article on fuel and octane ratings.. it will help us all out http://superchargersonline.com/content.asp?id=105

Brandon@Forged

Ahh I see.

Nano

iTrader: (1)

this is what the manual says

FUEL RECOMMENDATION
Use unleaded premium gasoline with an octane rating of at least 91 AKI (Anti-Knock Index) number (Research octane number 96). If premium gasoline is not available, unleaded regular gasoline with an octane rating of 87 AKI number (Research octane number 91) may be temporarily used, but only under the following precautions:

Zexy

iTrader: (55)

I cannot believe the technical advice on this site.

It is actually OK to not change you oil for 15,000 miles and run below 91 octane.

Kolia

iTrader: (2)

Yep, it reacts to knocking, after it has happen. The ECU probably records that event so that it will later retard timing in advance when the same conditions are met.

As a side note, I'd be curious to get a temperature reading of the exhaust valves when timing is "permanently retarded" from using low grade fuel. It's probably running hotter

Manufacturer say's I should run premium only. It's pretty much a no brainer...

Brandon@Forged

Check the information me and kolia have posted, we simply answered the thread starter's question...which was will regular fuel hurt my car, the answer is no, not one tank.

craniumdesigns

so you're required to use premium (91) on a Z? what about 89?

Brandon@Forged

Here's what i'm thinking. Nissan recommends a certain octane rating and you should stick to that if you don't want to run into warranty problems (hey, this is just a disclaimer, I don't want something freak happening and someone blaming me that the dealer looked over the ECU codes and found it had detected knock (doubt they can do this anyway) or reliability issues with your 350Z.

However, I would say it would be fine for long trips or if you are tight on cash (hey, $158 is over 12 meals at McDonald's ) to use 87 or 89 (I would use 89).

mikewagon

what if you put 91 in an older car like a civic thats suppose to take 87?