KCSKY7

Pretty simple question, just curious to see what grade of gas people are useing in their G's. I just recently purchased a '08 G37S 6MT Black on Black Fully Loaded and I have been using middle grade.

What about you?

Callaway

Premium only for me. This topic has been beaten to death btw.

whiddles

iTrader: (2)

^^^^ Same here 93 all the way. Sam please do not reply with 96,97,103 or what ever you have out there lol

SnoopDawg

I only use 93 and am trying to, as much as I can, stay away ethanol blends, but it's getting harder to find stations to do that.

dt22cc

You should be using premium 91 aki or greater. I believe your manual says something about it as well.

whiddles

iTrader: (2)

only only buy shell. its been a good source for me.

Blackjack

iTrader: (3)

Premium here as well.

g37mobbber

iTrader: (1)

premium for me as well the higher the better!

hispeed-lowdrag

iTrader: (7)

I ONLY ONLY ONLY use 93 (91 is the highest in some places). the manual says 91 or higher.

IF you are in a high altitude area (like Colorado) then using mid-grade is "acceptable" but I still use the highest octane I can find when I'm back in CO.

fmrlegend

on the loaner cars that i get from the dealer, the guy tells me just to put 87 wink wink. I'm like "alright"

but it sucks for those who buys these "dealer certified" used cars later on.

Arvig

As best as I can find at the local pump. All the places near me are only 91 octane, 10 percent ethanol blended in. If I knew of one that wasn't too far that had 93 octane and/or no ethanol I'd go there.

G37Sam

98 bro

Haha it is equivalent to the 93 you guys get in the US, just measured with a different stick.

Chekov

Is the month up-- when we’re due for one of our regular threads, this time on the “What octane to use” debate?

MechE

Why is it that premium is required if the compression ratio is only 11:1? (Just a question. Don't get all crazy on me)Other, lesser cars have the same ratio but can run on regular. Isn't octane rating just the resistance that the blend has to early detonation (knock) brought on by high compression ratios. For example, some Hondas run at 14:1 and require premium.

JohnEnglish

I run what the manual says which is premium.

There are a lot of factors that influence octane rating, cam profiles, combustion chamber design, timing, etc. All these thing influence the actual combustion of the air/fuel mixture and how the pressure of ignition is handled.