About Gas : 87 or 91 or 93???
09-21-2013, 07:38 PM
#47
Super Moderator
Costco Wholesale embarked on a program to blend their additive package at each Warehouse location serving up fuel. This permits meeting the higher standards, and delivering a consistent fuel mix across all markets where the equipment has been installed.
http://www.costco.com/gasoline-clean-power.html
http://www.costco.com/gasoline-clean-power.html
09-22-2013, 01:05 AM
#49
Registered User
If your car requires a high octane gasoline Premium 91 then you should only use 91 rated octane. Because our engines are built for high performance they burn at a higher temperature using Regular 87 will hurt your engine and fuel lines/pumps. My uncle's Acura RL requires premium 91 gasoline and he filled up with regular 87 when gas prices rose and his fuel line blew off because regular 87 couldn't handle the high temp and pressure. Don't be cheap you don't have a choice but to use 91 or higher octane.
I wouldn't use any other gasoline except Chevron, Shell or 76.
I wouldn't use any other gasoline except Chevron, Shell or 76.
09-22-2013, 09:57 AM
#50
Super Moderator
Our cars now use 11:1 compression (first gens were lower), so I can definitely see the requirement for higher octane in order to achieve the max. level of performance. However, as it has been proven many times over, running lower octane will work in almost any car designed to use high octane because knock sensors which communicate with the ECU will retard timing within milliseconds of sensing detonation.
Does retarding the timing decrease overall performance as the piston fires further from top dead center (TDC), yes, but will it cause long term damage? I'd have to say that I simply don't see how. unless there is a limitation on the ECU to retard -x number of degrees Below Top Dead Center (BTDC).
In fact, Telcoman (member here) uses 87 octane and he enjoys some the best mileage I have ever seen from a G (any generation) and I don't think he has ever had a problem with his car.
Does retarding the timing decrease overall performance as the piston fires further from top dead center (TDC), yes, but will it cause long term damage? I'd have to say that I simply don't see how. unless there is a limitation on the ECU to retard -x number of degrees Below Top Dead Center (BTDC).
In fact, Telcoman (member here) uses 87 octane and he enjoys some the best mileage I have ever seen from a G (any generation) and I don't think he has ever had a problem with his car.
Last edited by socketz67; 09-22-2013 at 10:04 AM.
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telcoman (09-22-2013)
09-22-2013, 04:09 PM
#51
Registered Member
Nope. Never had a problem in the 171796 miles that I put on my 06 G35 that I traded in August 2012
My current G37S loves regular and gives me great hi way mileage
Photo taken after a fillup and a 50 mile drive to work at 65 MPH
Much of what is being posted on this topic is total BS
I did a one month test years ago on my G35 using 91 for one month and 93 for one month.
MPG dropped and the test was a waste of money.
Returned using 87 octane and I've used it ever since.
I generally fill up at WaWA
Telcoman
My current G37S loves regular and gives me great hi way mileage
Photo taken after a fillup and a 50 mile drive to work at 65 MPH
Much of what is being posted on this topic is total BS
I did a one month test years ago on my G35 using 91 for one month and 93 for one month.
MPG dropped and the test was a waste of money.
Returned using 87 octane and I've used it ever since.
I generally fill up at WaWA
Telcoman
09-22-2013, 04:21 PM
#52
FWIW, here is what my 2010 Infiniti G37 Coupe Owner's Manual says on page 9-4:
Page 9-5 follows up with this:
I run premium fuel. 
FUEL RECOMMENDATION
VQ37VHR engine
Use unleaded premium gasoline with an octane
rating of at least 91 AKI (Anti-Knock Index)
number (Research octane number 96).
If premium gasoline is not available, unleaded
regular gasoline with an octane rating of 87 AKI
number (Research octane number 91) may be
temporarily used, but only under the following
precautions:
● Have the fuel tank filled only partially with
unleaded regular gasoline, and fill up with
unleaded premium gasoline as soon as possible.
● Avoid full throttle driving and abrupt acceleration.
However, for maximum vehicle performance, the
use of unleaded premium gasoline is recommended.
VQ37VHR engine
Use unleaded premium gasoline with an octane
rating of at least 91 AKI (Anti-Knock Index)
number (Research octane number 96).
If premium gasoline is not available, unleaded
regular gasoline with an octane rating of 87 AKI
number (Research octane number 91) may be
temporarily used, but only under the following
precautions:
● Have the fuel tank filled only partially with
unleaded regular gasoline, and fill up with
unleaded premium gasoline as soon as possible.
● Avoid full throttle driving and abrupt acceleration.
However, for maximum vehicle performance, the
use of unleaded premium gasoline is recommended.
Octane rating tips
Using unleaded gasoline with an octane rating
lower than recommended above can cause persistent,
heavy spark knock. (Spark knock is a
metallic rapping noise.) If severe, this can lead
to engine damage. If you detect a persistent
heavy spark knock even when using gasoline of
the stated octane rating, or if you hear steady
spark knock while holding a steady speed on
level roads, have an INFINITI retailer correct the
condition. Failure to correct the condition is misuse
of the vehicle, for which INFINITI is not responsible.
Incorrect ignition timing will result in knocking,
after-run or overheating. This in turn may cause
excessive fuel consumption or damage to the
engine. If any of the above symptoms are
encountered, have your vehicle checked at an
INFINITI retailer or other competent service facility.
However, now and then you may notice light
spark knock for a short time while accelerating
or driving up hills. This is no cause for concern,
because you get the greatest fuel benefit when
there is light spark knock for a short time under
heavy engine load.
Using unleaded gasoline with an octane rating
lower than recommended above can cause persistent,
heavy spark knock. (Spark knock is a
metallic rapping noise.) If severe, this can lead
to engine damage. If you detect a persistent
heavy spark knock even when using gasoline of
the stated octane rating, or if you hear steady
spark knock while holding a steady speed on
level roads, have an INFINITI retailer correct the
condition. Failure to correct the condition is misuse
of the vehicle, for which INFINITI is not responsible.
Incorrect ignition timing will result in knocking,
after-run or overheating. This in turn may cause
excessive fuel consumption or damage to the
engine. If any of the above symptoms are
encountered, have your vehicle checked at an
INFINITI retailer or other competent service facility.
However, now and then you may notice light
spark knock for a short time while accelerating
or driving up hills. This is no cause for concern,
because you get the greatest fuel benefit when
there is light spark knock for a short time under
heavy engine load.
09-22-2013, 04:54 PM
#53
Registered User
Getting almost 30 mpg at 65 while feathering the gas is almost a no-brainer in the G37. However, the typical rush-hour slow downs such as GSP, 287, turnpike through the construction, route 9 through Monmouth county, etc., where one goes from 0 to 50 to 0 in the space of 15 seconds, will send the gas mileage south in a hurry.
I only use premium 93 filled-up at top-tier gas stations such as Shell, Sunoco, Exxon, etc.
I only use premium 93 filled-up at top-tier gas stations such as Shell, Sunoco, Exxon, etc.
09-22-2013, 05:11 PM
#54
Senior Citizen
After over 50 posts in this thread going back three years, haven’t we discussed this topic to death?
Let’s go onto something new, like which is best, MT or AT?
Let’s go onto something new, like which is best, MT or AT?
09-22-2013, 05:14 PM
#55
Never used anything but 93 in NYC, and I've never gotten more than 18mpg, with
Few trips to Rochester and back and the best I got was about 23mpg?
Now that I think about it, my fuel economy info on my nav never stores the history...ever.
Few trips to Rochester and back and the best I got was about 23mpg?
Now that I think about it, my fuel economy info on my nav never stores the history...ever.
09-23-2013, 09:58 AM
#58
Administrator
iTrader: (9)
The car is designed for 91 Octane. That's what you use. If you don't have access to 91 Octane gasoline, then you go up to 93. Then, for the added cost and higher octane level, appreciate that you'll receive absolutely zero benefit what-so-ever from using 93 Octane.
People will tell you they use 87 Octane in their G just fine. Then again, some people believe we never went to the moon, and that fluoride in our drinking water is part of a mind-control scheme by Men in Black. Which it might be... but that's off topic. This very, very important topic.
Your car will run just find with 87 Octane, however the ECU will retard the timing a tick or two to compensate, and you will lose HP. Is it noticeable in daily driving? No, of course not. But it's still a lame, ignorant decision made by lame, ignorant people who somehow think they are more clever than automotive engineers. You know the type... the laws of physics for thee, but not for me.
For the life of me, I can't understand why people who buy a gas-inefficient car give a rat's azz about mileage. It's 3 flavors of nutty.
People will tell you they use 87 Octane in their G just fine. Then again, some people believe we never went to the moon, and that fluoride in our drinking water is part of a mind-control scheme by Men in Black. Which it might be... but that's off topic. This very, very important topic.
Your car will run just find with 87 Octane, however the ECU will retard the timing a tick or two to compensate, and you will lose HP. Is it noticeable in daily driving? No, of course not. But it's still a lame, ignorant decision made by lame, ignorant people who somehow think they are more clever than automotive engineers. You know the type... the laws of physics for thee, but not for me.
For the life of me, I can't understand why people who buy a gas-inefficient car give a rat's azz about mileage. It's 3 flavors of nutty.
Last edited by Rochester; 09-23-2013 at 10:12 AM.
09-23-2013, 10:04 AM
#59
Registered User
around here the only 91 octane available has ethanol in it. I don't use gas with ethanol. tge top tier manufacturers produce 93 without ethanol.
09-23-2013, 10:20 AM
#60
how about this...
A gas station 5 miles from me has 91 octane and they sell it as "premium". Most gas stations in Texas have 93 octane as premium.
I usually get 93 cuz its closer to me.
91 is usually 10 cents or so cheaper.
A gas station 5 miles from me has 91 octane and they sell it as "premium". Most gas stations in Texas have 93 octane as premium.
I usually get 93 cuz its closer to me.
91 is usually 10 cents or so cheaper.