once i get a full exhaust on the car and a test pipe to remove the cats i will be running only C16 VP race fuel. I have plenty of cans of that in the shop..

 

But…my buddy owns a ’03 Porsche Boxster which “requires” 93 Octane. Well…93 isn’t easily available in Nor-Cal, so he asked the dealer what to do. Ya know what their answer was??? - use what ya can get!! Straight from the dealer’s mouth. Now he hasn’t had any problems, so whose to say what the dealer says if he ever does have a problem………

 

you wont have problems. Modern engines can run on lower octanes, but you will loose power.

 

I think this is a perfectly reasonable and legitimate question. Premium fuel is not inherently any "better" than regular, nor does it have more additives. It is only more resistant to knock, and can provide more power in an engine designed to exploit that property. It is not available everywhere.

My last car also "required" premium fuel but in the owner's manual it stated that lower octane fuel can be used without damage, but with less power available from the engine. I assume that Infiniti has knock sensors in the G37engine that prevent damage if 87 octane fuel is used, but I have not heard an official statement from Infiniti to this effect.

I have also wondered if one could take into account the kind of driving anticipated with the next tank before filling up. For example if I am just going to set the cruise control and lope across Kansas by interstate, then what is the point of paying for more power than needed for the task at hand?

That said, I'd still recommend premium fuel because at this point the cost is not that much more than regular, and most people who buy a G37 are going to want all the power they can get.

Jay

 

First I am not sure why many people are being rude to the poster. $40 - $50k car isnt really THAT premium guys. Anyways, I am not sure that math of $150 savings in an year by inputing 87 octane gas. Especially in Canada, the gas price today I calculated would give approx 600 - 800 dollar differences per year on 87 and 91 gas. With the gas price keep going higher, this difference can get up to over 1000 dollars difference per year. So people will start to ask, do we really need 91 when we are just doing city driving and usually not go over 4000rpm.

I agree that when we purchase this car, we all understand we should put 91 octane gas into it. All premium car companies ask you to do that. However BMW dealer (my dad`s car) actually TOLD me it wont hurt the engine if you put 87 in it, but you will lose some performance.

 

Interesting the general consensus is use premium because you bought a performance car and spent a lot of money on it so don’t pinch the pennies.

So how many in this thread go to the dealer for ALL the service work. Don't cheap out now.

 

I've always taken all my cars to the dealer to be serviced. vv

You have to admit that it's silly for people to spend money on a luxury car and then complain about fuel costs. If you don't want to spend money on premium fuel during every fill up then buy a car that doesn't require premium gasoline.

 

(sigh) Here we go, resurrecting a thread with no posts in over 3-1/2 years on a topic that just won’t quit. Perhaps we DO need an “Official 87 vs. 91 Octane Thread” to combine the hundreds of past and future posts into one thread. Maybe we should even make it a sticky, in order to find it quickly and add it to our daily routine.

At any rate I must point out a problem regarding your math. Regardless of how high the price per gallon gets, the difference between 89 and 91 will still be around twenty cents (at least in LA), so whereas the total cost of filling up may rise, the difference may not change at all. In other words, even if gas goes to $10 per gallon, you would still only save that $150 per year you mentioned if using the lower octane.

 

Ugh, I didn't notice the date. Lock the thread.

 

Hi, I accidently filled up on 87 instead of premium 93 (the stupid gas station put the 87 at the end which confused me and thought it was 93 until i was done filling did I notice that the middle one was actually more expensive and then notice it says 93), how badly would that affect the engine or my car? I have the 2010 G37xS. Please help.

 

i really dont see why you would use cheaper gas just to save 4 dollars a fill up

 

Not hurting it at all. As stated here, you'll have some reduction in power and gas mileage. You've probably used that tank up by now (a week later), but if not, you could top it off when it's half full and the car should feel "normal."

 

LOL....so 3.5 years later and NOBODY has posted anything like that yet.

I guess it's safe to say 87 octane will not blow up (or otherwise damage) the VQ engine. Knock sensors are a beautiful thing...they protect the engine from any potential knock/ping when the cheapskates fill up on 87 octane fuel and then drive the car like they stole it.

Isn't it funny how Nissan/Infiniti had the foresight to consider that exact scenario and therefore install knock sensors on the engine block? I mean, seriously...they are providing a warranty on the drivetrain, so I guess it makes sense for them to build in protection, huh?