Choice of gasoline

Okay I have the argument about the Octane, now would someone quote the all so grand statistics about how much life is taken from a cars engine, that uses less than the required octane rating.

Am I losing an average of 2k miles per year after using 89 instead of 91?
Are there any studies that show this? Maybe this would be more concrete than the Octane rating verbage.

And my NSX is friggin Disposable as is everything else in my Garage. I simply decide how and at what rate I want to dispose of it. :wink:

"When it starts appreciating instead of depreciating, it will become indisposable."
 
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nsxtasy said:
"Your NSX is designed to operate most effectively on premium unleaded gasoline with a pump octane number of 91 (research octane number of 96) or higher. If you are unable to find premium unleaded gasoline, an unleaded regular may be substituted. The engine will compensate for the lower octane, but you may notice a decrease in power as a result."

The manual tells you to use premium, NOT that this is in any way optional. The only condition under which it permits using non-premium is if you are unable to find premium unleaded gasoline, and no other circumstances.
I disagree with your interpretation of this statement Ken - indeed I would say this actually endorses the fact that you can run with lower grade gas & that the only detractor is that it will not run at optimum power. It does not state superlatives like "under no other circumstances" as you are suggesting. It also does not "tell you" to use premium - it advises that "the NSX is designed to "operate most effectively" using 91 or better.
You could instead choose to focus on the actual statement "an unleaded regular may be substituted" as the most defining statement as to whether it is allowable.
Yes, it does not go so far as to offer it being optional, but definitely is not saying it's prohibitive either. The only caution is that you should expect a decrease in power if you do. There is nowhere that suggests this will cause any damage to your engine.

All that being said, I prefer my NSX to operate at peak efficiency and use the best gas available, which is "only" 91 in CA.
 
I don't understand why many of you think thr reason I started thid thread was to save a few bucks. NO NO NO! As you can see there are some disagreements out there on this topic.

I have limited knowledge on this and just wanted to see if you guys with more experience have to say. appreciate all the links and inputs. There is no need to ASSUME I was cheap or dumb(as suggested by Ken).

Like NSX 2398 said this is a scientific question from someone who just want to know more. I do appreciate his understanding comment in his response.
 
D'Ecosse said:
I disagree with your interpretation of this statement Ken - indeed I would say this actually endorses the fact that you can run with lower grade gas & that the only detractor is that it will not run at optimum power. It does not state superlatives like "under no other circumstances" as you are suggesting. It also does not "tell you" to use premium - it advises that "the NSX is designed to "operate most effectively" using 91 or better.
You could instead choose to focus on the actual statement "an unleaded regular may be substituted" as the most defining statement as to whether it is allowable.
Yes, it does not go so far as to offer it being optional, but definitely is not saying it's prohibitive either. The only caution is that you should expect a decrease in power if you do. There is nowhere that suggests this will cause any damage to your engine.

All that being said, I prefer my NSX to operate at peak efficiency and use the best gas available, which is "only" 91 in CA.


Send me a truck Ken, I will get you some 93 right out. However, your 91 may be as good as some of the 93 here.
 
fannsx said:
I don't understand why many of you think thr reason I started thid thread was to save a few bucks. NO NO NO! As you can see there are some disagreements out there on this topic.

I have limited knowledge on this and just wanted to see if you guys with more experience have to say. appreciate all the links and inputs. There is no need to ASSUME I was cheap or dumb(as suggested by Ken).

Like NSX 2398 said this is a scientific question from someone who just want to know more. I do appreciate his understanding comment in his response.

For the record I had the same questions as you. But my motives are different. I am as cheap as they get. :smile:
Ken was speaking in term of the action itself as he views it rather than the person commiting the act.
Do sweat it things get a little passionate around here when you Talk Gas, Wax, or FI... :wink:
Keep posting.
 
The trick is using what the engine needs.
Too much, and your wasting money.
Not enough, and your engine won't like it.
(whether you know it or not)
Lots of this stuff on other boards where guys with 11.5 to 1
60's V8's are trying to get by "retarded" on 91 pump gas.
JMHO
 
Ken, don't assume that because we all bought a "high-performance supercar" that we all use it to the limits to which it was designed. I happen to use mine as a "great-looking daily driver" and, as such, to me it is still worth everything I paid for it. But just as you wouldn't waste money putting 93 octane in it instead of 91, I choose to not waste money putting 91 in it when I feel it isn't req'd.

I would “waste” money on 93 if I could get it.
The same way I waste money on my aircraft engine by using fuel and oil that way exceeds the requirements. I consider it cheap maintenance.

I do applaud your asking the question. I like the fact that you have a scientific approach and you wont take anybodies word for anything, even Honda. You are not a sheep. I think that some of the other guys are being a bit hard on you.

So it’s up to you to do the experiments and gather the data and let us know. Personally I can’t afford to do that and if I was going to push the limits I would do it with my lawnmower.

Keep questioning everything!

Kind regards,

Patrick
 
hehe not to be a jack a$$, but since were talking gas and stuff

whats the deal with ethanol fuel additive, here in st. louis its at most of the pumps. i never really noticed it before in NC so i guess its a MW thing?

anyhow its just kinda funny cuz the car manual mentions something about the maximum % of ethanol in the gasoline you should use is 10%. LOL well guess what alot of the pumps in my area have 10% ethanol in it LOL WTF! :cool:

dont know what this oxygenated gas is for exactly, anyone care to enlighten me while were on the fuel subject :biggrin:
 
Your compression ratio in a non forced induction car dictates what octane you need to run. The higher the compression ratio the higher octane you need unless you pull timing to prevent knock.

With forced indicution it is a combination of compression ratio and boost. Again you can pull timing out to prevent knock or detonation.

You can get the compression ratio/boost so high you need race gas. This is why you see some forced induction people comment that they made 500rwhp on pump gas.

If you car recommends 93 then that is what you should run to prevent the risk of detonation.
 
D'Ecosse said:
I disagree with your interpretation of this statement Ken
Well, then we will have to agree to disagree. Because here is what they DON'T say in the owner's manual:

"You can use octane of 87, 89, 91, or higher in your NSX. Performance will be higher if you use 91 or higher than if you use lower grades."

They don't say anything like that (although that appears to be the way you prefer to interpret the actual statement). In the actual manual, they are clearly NOT recommending the use of lower octanes in any circumstances other than absolute necessity. THAT'S the distinction I was trying to make. I don't interpret; I read their statement literally, and don't substitute another interpretation at all.

The simple fact is, the owner's manual is the best guide to the care of your car, and it was written by the people who designed and built it. (Same with the NSX as with any other car.) If you want to follow its advice, then use premium gasoline whenever you can. If you don't, heck, it's your car...
 
khappucino said:
whats the deal with ethanol fuel additive, here in st. louis its at most of the pumps. i never really noticed it before in NC so i guess its a MW thing?
Briefly, the federal government mandates the use of oxygenated gasoline in many areas throughout the country with unhealthy levels of air pollution, some just in the winter, and some year round, as noted on the EPA website. In most of the Midwest, gasoline is oxygenated mostly through the use of ethanol, whereas other parts of the country often do so using MTBE. (There are economic and safety downsides to each additive.)

Another thing that may affect whether or not you notice it is that some states require that the use of ethanol be labeled on the pumps, while others don't.
 
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nsxtasy said:
I don't interpret; I read their statement literally, and don't substitute another interpretation at all.
Ken, you're hilarious!! First of all you artificially create text that doesn't exist and then you try to debate the fact that it's NOT in the manual and then you claim you don't substitute other interpretations? That's absurd!

And then you go on to claim that the manual talks about "circumstances other than absolute necessity" but when I re-read the text from the owner's manual, I can't seem to find those words .. or words like "in an emergency" or "as a last resort" or "if you've got a fat wallet for repairs".

Let's face it. Car companies are risk averse when it comes to warranty claims and owner's manuals are chock full of warnings for things they don't want you to do. If there was the least chance that they were going to be on the hook for the kind of warranty repair bills that you're insinuating, the manual would say "trailer the car to the closest Premium pump".
 
Anyone uses other than premium gasoline for the NSX?
That was the topic of this thread so:
Yes, I use MIDGRADE all the time. Thats for one year straight.
I have used premium when the price was right and there is a great difference in performance. Enough that you can know and feel it.
Thanks for asking!
tRev
p.s. I also drive on ALL SEASON tyres!
 
NSX2398 said:
Ken, you're hilarious!! First of all you artificially create text that doesn't exist and then you try to debate the fact that it's NOT in the manual and then you claim you don't substitute other interpretations? That's absurd!
Obviously, you don't understand what I was saying. Apparently you did not bother reading my post carefully. I can only conclude that you're just trying to insult me by changing the meaning of my post.

What I CREATED was a paraphrasing of DEcosse's interpretation - NOT MINE - to show how HIS interpretation differs from what is written in the owner's manual. That distinction is neither hilarious nor absurd, despite your lame efforts to ridicule it.

NSX2398 said:
And then you go on to claim that the manual talks about "circumstances other than absolute necessity"
Absolutely not true. Again, you are misquoting me. I clearly said that the manual does NOT refer to any circumstances other than absolute necessity. The ONLY circumstance they refer to, in connection with the use of lower octane fuel, is "If you are unable to find premium unleaded gasoline", which would seem to be the same thing as "absolute necessity".

NSX2398 said:
Let's face it. Car companies are risk averse when it comes to warranty claims
That's right. They want to minimize their warranty claims, and in order to do so, they give you advice on how best to take care of your car. It's up to you whether to follow their advice or to ignore it. And that's true of the maintenance schedule, the proper fuel and other fluids, etc. If you want to use fuel or oil or brake fluid or transmission fluid that's different from what the owner's manual tells you to use, or if you want to never change those fluids at all, that's your decision, because it's your car. However, it will be your responsibility to pay for any repairs that are necessary as a result of ignoring that advice, just as it will be to your financial detriment if your car sells for less money when that advice is ignored than when it is followed. Maybe there won't be any repairs, but maybe there will; maybe you'll be able to find a buyer who will overlook such care and pay the same price for your car, maybe you won't. That's what a risk is - a possibility, not a certainty. And those are the risks you take on when you ignore the advice in the manual; if you feel comfortable with them, then by all means go ahead and do so. I don't, with my car.
 
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Just lighten things up here!!! This is my 17 year old daughter in the passenger seat when I drive the Nsx with Mid-Grade gasoline.
Wonder what would happen it I used Premium?
tRev
 
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ffffanman said:
Just lighten things up here!!! This is my 17 year old daughter in the passenger seat when I drive the Nsx with Mid-Grade gasoline.
Did you crop that photo? :D
 
Here is some intersting reading on the topic of octane requirements.
As you will learn, many factors influence a particular engine's octane requirements including compression ratio, engine management systems, ambient temperatures and the actual age of the engine.

Link 1

Link 2

Link 3
 
ffffanman said:
I have used premium when the price was right and there is a great difference in performance. Enough that you can know and feel it.
Thanks for asking!
tRev
p.s. I also drive on ALL SEASON tyres!
I guess there is a bigger difference in price between different grades of gas in Canada? We go up 10 cents/gallon for every grade usually.
 
fannsx said:
I guess there is a bigger difference in price between different grades of gas in Canada? We go up 10 cents/gallon for every grade usually.
Yes, but 10 cents in the United States is equivalent to around 5 Canadian Dollars. :D

(Ten cents U.S. is actually around 12.6 cents Canadian right now. I don't know what the price spread between grades in Canada is though.)
 
nsxtasy said:
Yes, but 10 cents in the United States is equivalent to around 5 Canadian Dollars. :D

Too funny unfortunately too close to the truth :tongue:

(Ten cents U.S. is actually around 12.6 cents Canadian right now. I don't know what the price spread between grades in Canada is though.)

There is about 5 cents/litre difference between grades where I live which works out to approx 38 cents per US gallon between regular and premium. :eek: Even so, I wouldn't use anything but premium in my NSX or CL.
 
Ken, no cropping or altering, thats Jordan messing around on the way to her staring role in her latest play. We do have so much fun together, she is my best friend. You should see the rest of the photos.
I filed up with premium on Saturday cause you guys made me feel bad for mistreating my car. I'll give her a whirl for a month and see what I feel. I am enjoying the abs and traction control back on. Replaced those fuses back into their slots on Saturday as well.
tRev
 
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