I was wondering what octane rating gives the best performance and mileage for everyday driving. Here in Dubai we have a choice between 91, 95 and 98. And also does it affect the motor if they're mixed.

 

In CA, 91 Octane is pretty much the best you can do.
Also has 10% Ethanol, just to make things worse.

 

The LT1 engine requires premium but you could use 89 or 87 octane if premium were not available. The engine won't have the power that premium provides but it will run until premium fuel can be found. That's not an issue for you so your C7 will be fine with 91 or 95 octane. You can mix them up with no problem. The 98 octane you have access to probably won't do anything more for the engine but someone with track experience may have another opinion.
I use 93 octane and my Stingray run fine.

 

The octane ratings are calculated by different methods around the world. And, in the eastern U. S. 93 is available, but in the western U. S. 91 is the highest. If you have 3 grades, they are most likely regular, mid-grade, and premium. So, use only the premium. It doesn't hurt to mix grades, but the C7 REQUIRES premium. Older Corvettes premium was RECOMMENDED.

From owner's manual 9-51:
Use premium unleaded gasoline
with a posted octane rating of 91 or
higher. If the octane is less than 91,
you could damage the engine and
may void your vehicle warranty.
If heavy knocking is heard when
using gasoline rated at 91 octane or
higher, the engine needs service.

Use of Seasonal Fuels
Use summer and winter fuels in the
appropriate season. Driving or
starting could be affected if the
incorrect fuel is used. Drive the
vehicle with the engine running until
the fuel is a half tank or less, then
refuel with the current seasonal fuel.

Prohibited Fuels
Gasolines containing oxygenates,
such as ethers and ethanol, as well
as reformulated gasolines are
available in some cities. If these
gasolines comply with the
previously described specification,
then they are acceptable to use.
However, E85 and other fuels
containing more than 15% ethanol
must be used only in FlexFuel
vehicles.

Fuels in Foreign Countries
If planning to drive in countries
outside the U.S. or Canada, the
proper fuel might be hard to find.
Check regional auto club or fuel
retail brand websites for availability
in the country where driving. Never
use leaded gasoline, fuel containing
methanol, or any other fuel not
recommended. Costly repairs
caused by use of improper fuel
would not be covered by the vehicle
warranty.

http://en.wikipedia.org/wiki/Octane_rating

 

Last time, I filled up with 93 octane, ethanol-free.

 

Research Octane Number & Motor Octane Number are vastly different.

Long story short: it's a sports car - put the highest octane possible in the tank. Beyond that, google is your friend.

 

GAURAV, Here in the UAE the gas has a RON rating not an Octane rating
91 RON = 89 Octane
95 RON = 91 Octane
98 RON = 93 Octane
So if you just pull up to the pump and ask the attendant to fill it with "Super" and not "Special" you will be fine.

 

I use 91 non-ethanol most of the time. I can find 93 E10 locally but prefer the E0.

 

Here in the SE, 93 octane is premium and I use the COSTCO brand exclusively. If on the road though, I'll try to get Quick trip

 

The highest I can get. Usually 93 octane.

 

has anyone filled up with 87 and could they perceive any knocking or pinging?
......seems like some remote areas may not have premium......maybe carry a bottle of octane booster?

 

Wow. Thank you so much everybody. I love the effort put into posts to make a CF brothers life simple. You guys are awesome

 

That is almost, but not quite correct. There are two octane rating methods, research and motor, abbreviated R and M. The R number is about 10 higher than the M number, but it can vary a bit, in the range of 8-11 higher. The US and Canada use the formula (R+M)/2 to post the octane number on their pumps, while Europe and the Middle East use just the R number. Since R is 8-11 higher than M, then R is 4-5 higher than (R+M)/2. So if you are in Europe or the Middle East and see pump postings of 91, 94, or 98, those are in “R number”, and are equivalent to US or Canada postings of 87, 89, or 93 in “(R+M)/2 number”.

 

I have had good experience with costco gas and it is decently cheap compared to other stations near by and also I get 2% cash back on my amex

 

93 at any "name brand" station.

 

Ethanol really sucks, you can thank our government. Where did you get 93 non Ethanol?

 

Chevron 93 octane and in a pinch Shell they are top tier gas.
z51vett
Doug

 

Sounds like the OP should use the 98.


I run 93.


Elmer

 

You won't hear any knocking, because there are knock sensors, and the PCM will switch to a low octane fuel timing map if it detects more than momentary knocking.

 

Shell V-Power 93-octane is my typical fill here in Texas. While in Minnesota I use BP 93. Both are E10 fuels.