Running 87 vs 91 will have no negative effect on the engine what-so-ever. You and others are just running your mouths. I bet you don't even know why you'd want to fill up with premium beyond the fact that Nissan recommends it. And you say the car was designed for premium - are you a Nissan engineer? Did you help map the fuel curves in the ECU? From what source do you support your statements?

Furthermore, it's silly to speculate that just because someone chooses to fill up with 87 over 91 that they'd forgo oil changes and fixing minor problems. Thus, it has no affiliation with your argument. So, no, that does not explain "WHY." Please, with applied reason and logic, forgo speculation and self-conclusion, explain to me WHY you'd feel sorry for someone who has purchased car which demands unleaded gas only with the recommendation to use premium that has, for the past some-odd years, ran only regular unleaded.

 

Other than getting better performance from a higher octane fuel, I really dont know that there is any adverse affects from running regular as opposed to premium.

 

I pump premium.. some people pump 87 octane but just wondering does 91 octane increase the life of the engine? or is it the same as 87 octane?

 

READING > YOU

It clearly states 87 may be used temporarily and you must replace it with Premium ASAP. Also, you must not step on the gas full throttle while on 87. This applies to 6mt Rev-up motors.

 

All you're doing is quoting the manual for the car though. Just because the manual says thats what gas you should use, doesn't mean that thats a requirement for the engine to function.

However, having said that, it is common knowledge that a higher octane fuel will burn more efficiently than a lower octane fuel. But, that does NOT mean that a lower octane fuel will DAMAGE or adversely affect your engine. As a matter of fact, I would venture to say (without searching myself) that there are literally no FACTs stated anywhere that a lower octane fuel (i.e. 87) will cause any damage at all to an engine.

Not saying thats what I use, because I use premium as well. Im just saying that saying 87 octane will hurt your engine is not true. It just wont function at peak potential.

 

read the ****en thread from page 1.. god.. your just another one starting this all over again... and then, there is another dude, saying why the other dude is quoting the manual... well are you both nissan engineers? no right.. so stfu... atleast the other dude is getting his info from the people that made the car..

even if you were an engineer or your buddy's friend's cousin was... who cares.. you didn't design the car.. i bet if i gave you my unix box, you wouldn't even know where to begin unless i told you what command does what because my flavour of it is different ,scripted the way i want it to work.. maybe bad example .. **** it..

and i simply said i felt sorry for the next owner because the majority of owners pump premium...

my last post on this thread.. nissan is dumb for recommending **** that doesn't make a difference when they could clearly sell the car for a better crowd with regular fuel recommended which would then also help with the annual fuel cost...

jibberjabbers.... dont' waste your time with this dude.. he is like the other guy from page 4 that is going to start this all over again.

 

I alway pump premium.why do my car bad and be cheap?if you really look at it, it's only $1-2 dollar diffrence.I smoke and drink so why not spend that extra money on my car..I take care of my car and in the long run it'll take car of me..you can pump regular gas all you want but in a few years my car will run better than your,because I pump premium and take care of my car...

 

hahahah wtfff HE CALLED HIM A TROLLLL ahahhahaahh

and stop fighting.....whoever wants to put premium go put premium, and whoever doesnt love there car go put regular simple. Its relatable to a human person.....in theory we can run on junk food alll day but it will be doing horrible things inside, with a proper diet like recommened (premium gas) helps longetivity and better preformance

 

This argument is not about the price difference. I'm sure very few of us care about that. It's idiots like T7n7 that can't even put a grammatically correct sentence together to prove a point that I'm speaking out against.

Good. Get out. You can't even prove your point with a coherent argument. All you do is mindlessly rant. I have read the thread an no one has put forth a decent argument why 87 < 91. Everyone seems to fall back on the "cheapskate" argument but fails to put forward a reason to why the VQ would require 91. No one has quoted any reason why temperatures in the cylinder would ignite before spark induced detonation on 87 rather than 91. A simple argument of compression ratio would even suffice. Instead, you guys quote owner's manuals of merely "recommended" octane levels. The amusing part about this is I'm sure most of you who purchased a new G ran it to red-line a couple of times during the manual's suggested "break-in" period (even though many sourced say say you do not need a break-in period as engines are routinely checked before installation).

If you ever decide to search, you'll find that higher octane isn't required until the compression ration pass 10:1. But even then, higher performance motorcycles with 12:1 ratio will still not require premium. In fact, I've read that using 87 has actually produced slightly more horsepower than 91 in the Ducati's 996.

But here's an article by USA Today that made me laugh, while reminding me of you guys:

Why use premium gas when regular will do?
By James R. Healey, USA TODAY


http://www.usatoday.com/money/autos/...emiumgas_x.htm

 

Don't argue with an idiot. They will take you down to their level, and beat you with experience.

 

So many opinions in this thread...

I just got a used g35 and I want to know is there anything wrong with using regular?

I understand there are negative impacts like lower performance, but is there any chance of damaging anything?

 

^For GOD'S SAKE NO!!!

Wow... dude... wow. So ignorant. I find it amusing that when facts that are provided by extremely incredible sources are thrown in your face you resort to insults.

Although it seems like you haven't read my previous post, I'll still post this lnik:

http://www.caranddriver.com/reviews/...emium_feature/

Note the Sabb is F.I. and the M3's S54B32's compression ratio is 11:1


Suck on that.

 

You've obviously never tuned a car to use high-octane race fuel.

If you knew anything about the basics of internal-combustion engines, you'd know that ignition timing can be advanced when higher-octane fuel is used, resulting in more power. The timing is advanced manually in a car using a distributor system, or electronically using the car's ECU.

The Infiniti ECU leverages a knock-sensor that will retard timing when lower octane fuel is used, resulting in less power. No long-term damage is typically done, because the ECU will use timing retardation to prevent knocking, however there are some situations where knocking can occur briefly causing undue stress on engine components (e.g., if the ECU has not yet retarded timing for the first engine revolutions on start-up).

Go ahead and run 87 octane in your G... my tail-lights are pretty to look at.

And continue being an ignorant and uninformed ***-hat. It's entertaining.

 

Right....

And yeah, actually, I have tuned a car for higher octane fuel. That's why I'm making my arguments. I had a completely street legal (cat and all) DSM, full weight run high 12s on pump at 4200 feet. And I just used a piggyback to tune. However, I was running a large turbo at high pressure (both variables far outside the stock conditions) which produced much hotter air in the combustion chamber. Thus, the highest pump octane was required along with additional A/F ratios along the RPM band.

However, we're not discussing modified cars here. We're not discussing piggybacking the ECU and tuning the VQ35 for higher performance. We're talking about a stock G35 and effects when using 87 vs 91 octane. You've probably skipped over all the sources I have provided (none to which you have provided) that claim running 87 vs 91 has no noticeable difference. Just because 87 has lower octane levels than 91 does NOT mean that the ECU will automatically pull timing. It only does when the knock detector detects knock. The engine will only produce knock if air temperatures in the combustion chamber reach ignition point before spark detonation. Running 87 vs 91 on 10:1 compression will not produce a sufficient amount of knock to lead to a significant pull in timing that produces a drastic drop in an output of horsepower.

However, based on your analogy of "leverage knock-sensor," one would assume that the higher octane you run the ECU will increase timing. Thus, no tuning would be needed if the ECU could supply the optimum A/F ratio against any modified application used. If this were true, people would simply fill up with race-fuel for an automatic increase in power, every time. Why bother with piggybacks and/or taking your car to get tunned when all you have to do is add higher octane and the ECU magically works it out for you?

And your childish remarks against me are laughable. I'm the only one providing sources and outside knowledge. ****, I even quoted the head of Nissan USA's powertrain division! And you assume that I've never tunned a car and call me an ignorant a**-hat? Grow up.

 

The ECU does not advance timing beyond its factory-default setting, which is optimized for 91 octane. The knock-sensor will come into play at lower octane levels. The ECU does not advance timing beyond its default factory default.

Most modern ECU's come from the factory just like this--it's not unique to Nissan/Infiniti.

There... did I spell it out for you simply enough, or do you wish to continue your rant, Mr. Tunner [sic]?