My first tank off the lot from dealer was 87, the mileage was 13.8L/100km. After fill with 91 for second and third tank and reset the meter, I got 11.1L/100km constantly in break-in period.

 

All - a note about Octane Boosters:


When an Octane booster claims to increase the octane rating of gasoline by X points it may actually do so but keep in mind the math is as follows:

Gasoline: Octane of 87
Additive: Claims to increase by 5 -points
Math: 87.0 + 0.5 = 87.5 (CORRECT)
NOT: 87.0 + 5.0 = 92 (NOT CORRECT)

Do not bother with Octane boosters - just pay for the gas and save actual dollars with actual MPG, product costs and environmental benefits (packaging of said mythical product).

As for gasoline, modern engines can actually suffer with lower octane even if you dont "notice" it. Exceprt from Car and Driver:

Regular or Premium? - Feature - Car and Driver

\--
Our tests confirm that for most cars there is no compelling reason to buy more expensive fuel than the factory recommends, as any performance gain realized will surely be far less than the percentage hike in price. Cheapskates burning regular in cars designed to run on premium fuel can expect to trim performance by about the same percent they save at the pump. If the car is sufficiently new and sophisticated, it may not suffer any ill effects, but all such skinflints should be ready to switch back to premium at the first sign of knock or other drivability woes. And finally, if a car calibrated for regular fuel begins to knock on anything less than premium or midgrade, owners should invest in a tuneup, emissions-control-system repair, or detergent additives to solve, rather than bandage, the root problem. Class dismissed.
--\

 

I understand what people mean when they want to run regular.

A lot of people come from civics and corollas which fill the tank up for 35 dollars which go 300 miles and they come to g37s which fill up for 80 dollars for the same 300 miles. This is kinda a buzz kill.

A lot of other people also say that its only a 10 cent difference, well guess what, its not. where I live the difference between regular and premium is around 50 cents. for a whole tank, thats 10 bucks. Also, these people only get 20 mpg or as I get, 15 mpg (100 percent city) while on their civics they get 25-30 mpg (what I was getting 100 percent city too)

this is a huge difference. Compared to other cars in their class such as a bmw with twin turbo... yes the 335i, it gets around 23 city on premium which is reasonable!

I wanted to run regular when I first got my car. After dishing out 35k for my car, I did not want to put so much money just for gas. 6 months have passed, and I have learned, that premium is the way to go. It is not the fact that I realized that its a 35k car and that it should take regular and get better mpg, but I realized that the original reason I got the car was for pure enjoyment. The power of 330 horses under my hood. The luxury that it offers that I did not find in the 3 series bmw. It is a headturner car and the reason I wanted to get it at first was because I wanted the power. I did not go with the 335i because of the problems with the twin turbo. Did not go with the 328, because its just as slow as an accord. Did not go with the evo, because it was too light, Did not go with the benz. because well I dont find the benz line appealing besides for the c63 which was out of my price range. Also, the m3 had a gas guzzler tax at the end of the year. The g37 was the perfect fit for me. Sporty, had AWD, 330 horses ect.

Gotta admit, the g37 is a gas guzzler. So what people do not realize is that when they run regular, they only get around 10 mpg instead of 15. for that 50 cents, I think the 5mpg extra is worth it for 50 cents, do you not?

Just for the information, if you are running 89 octane on our g, your car will give off a lot more heat. Also, 91 is required, putting 93 in will not give you better mpg. 100 octane gas is sold as well for 5 bucks a gallon. Does not improve mpg after you go over 91 octane gas.

BUT.... What I do is fill up tank till max with 93 octane gas, when it reaches 1/4 way down or a little more than that, fill it up with 89 octane, and after both grades of gas mix, it will be at about 92 or 91.5 octane. I do not wait till it reaches halfway. I do it a little before just to be on the safe side, then use all the gas in my car till I reach E. This saves me a buck or 2? maybe even 5? thats a subway footlong sandwich.

 

My salesman told me i could use regular in the car too...being that I owned a G35 coupe before the X coupe I got last week, I laughed in his face.

 

This. If you have a half tank of 93 octane, you can fill up to 10 gallons of 89 octane and still be within tolerance. All 89 octane is really is a blend of 93 and 87 mixed from the truck when they deliver the gas to the station. I always ran premium in my old altima coupe 3.5 SE, in 2008 they recommended it for maximum performance. It could have easily ran on 87, but the performance and gas mileage would suffer. I found the difference in mileage made up for the additional cost of the gasoline, and the added performance was a benefit. If you have ever spent any money on performance mods for your car, it makes no sense to not use premium all the time.

 

Get a chase freedom credit card. 6 months of the year (jan-mar, jul-sep), they give 5% back on up to $1500 in fuel purchases.

I use the card to buy gas gift cards to use during the non promo months. Saves a little ($50 on $1000 worth of gas). Makes that $4/gal premium feel like $3.80/gal

ymmv

 

Guess I don't understand people getting a G and then act all surprised about the gas it requires and it's mileage .....

 

Ya, I wont say I don't agree with this statement.

Seriously people. If you wanna run 93, then put 93. If you wanna run 87, then put 87. It's not that big of a deal, and you're not saving anything but a few bucks, and kahboom is right...that shouldn't break you. This isn't the 1960's where cars are running leaded gas and theres a lack of close tolerances in engines. Sure, you'll notice a performance drop from 93 to 87, but it ain't gonna do jack squat to your engine in terms of harm.

I will, cause I'm a conspiracy theorist, agree with the statement that the auto manufacturers are in kahoots with the oil companies. If they weren't, then we'd certainly see WAAAAAAAAYYYYYYYYYY more hybrids and electric cars than we do.

 

No, I don't. Your Mobil 1 anecdote would be more akin to Infiniti recommending that you only fill up with Shell gasoline. Recommending the gasoline octane is more along the lines of what viscosity oil they tell you to use.

 

That`s weird, my salesman told me USE ONLY PREMIUM period. And that`s all I`ve been using since I got the car .

 

Am I the only one with the sticker on my gas door that specifically states "use premium gas only"????...instead of asking questions i just follow directions lol....just saying

 

I am not sure why this is even a discussion................................if you have a warranty on your car you should follow the manufactures recomendations to the "T" period.

 

Put in what you can. My camaro called for premium, but that last 40K miles of my 80K mile ownership I put in regular. The car didn't drive as well, and overall driveability deteriorated over time. The G calls for premium, it gets premium.

 

I use diesel. Higher energy content.

 

lol.

dafuq?