I notice no difference in fuel economy or power when i run 91+ or 87 octane.

I've settled on running 89 octane. At this point, ive run that for almost 60K miles so it's just what I use now

 

Mmm pretty interesting. I knew a girl who just used regular in her G and get engine sounded horrible tho that could have been due to a lack of overall maintenance

 

I used almost 100 gallons of gas for the round trip from NJ to Florida.
At roughly a $0,40 increase in the cost of premium over regular 87 that savings comes to $40.00 just for this trip. Not sure where your $62.00 figure comes from?

I previously did a one month test with my previous 06 G35 using 91 octane for one month and 93 octane for one month carefully calculating my MPG
I got better MPG using 87 octane and have used it for having driven over 200,000 miles on my two Infiniti's

My current 2012 G37S has never seen a drop of anything other than regular 87 octane usually purchased here.



BTW dealers deliver new vehicles with a full tank of regular.

Telcoman

 

No cruise control, steady speed rarely going more than 5 MPH over the speed limit.
I 95 is 65MPH in some places and 70 MPH in others between NJ and Florida
EZ Pass enables no stopping at toll booths.

Lots of police all along I 95 pulling over speeders.
The Waze App is useful for pointing out where the police are

Telcoman

 

It depends on the terrain. I live in SoCal where its just a series of hills everywhere, so I get between 23-24 combined hwy/cty. On a trip to Vegas tho, where the terrain is relatively flat, I get around 30. There's no real secret snake oil, its just about having a well maintained vehicle and not stomping on the gas.

There's nothing you can put in your car, or secret tip or trick that's just gonna get you to gain 10mpg. The G is naturally kind of thirsty and we all like the throttle.

So, change yer plugs, change your air filter, keep your tires inflated, get an exhaust that flows more freely and watch your launches and speed. That's really all you can do.

 

You are correct!

My tires are at 35lbs when cold
Air filters get changed every 10k miles



The plugs on my previous 06 G35 were changed at 106k miles

On trips to Vegas i would assume you would see slightly better MPG if you made the trip at night when it is cooler.
I get slightly better MPG at 65 to 75* than I do at temperatures in the 90's or in the twenties in winter

Idling in traffic, frequent stops and starts kill the MPG in a G

On the road on long trips it is great.

Telcoman

 

I see much less mpg in cold weather, yes.

I keep my tires at 50psi the tho. Max that **** out.

 

The $62 was an exaggeration, but here our system is an extra $0.10 per grade so based on filling up once week that's about $150 a year, so its not that big of a deal.

It does make sense that you would see slightly better mpg from running 87 as opposed to 91 because there are less additives, and gasoline stores more energy than the additives that are in it. It would be negligible, however.

It is absolutely fine to run 87 in the G because the G like most OBD II cars is equipped with knock sensors and it will pull back the timing when it senses detonation, this is at the cost of power tho. It says premium fuel only because all the tests Nissan did to developed that motor were done with premium fuel, so if you want the performance that they advertised, premium is an essential part of that.

I won't run 87 even tho I know its fine, because $3 a week isn't that big of a deal and if I can get max performance, why not?

 

not for nothing but I'd love those gas prices in south florida

 

Well even tho your grades go up by $0.20 per grade, our gas is still more expensive. I pay about $4.27/gal right now. It sucks.

 

Ouch yea that hurts...we're at about 4 to 4.15 depending on where you fill up.