# 87 vs 92 Octane



## snowwy66 (Nov 5, 2017)

GM has been recommending 87 since the beginning of time.


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## alanl11 (Apr 8, 2018)

snowwy66 said:


> GM has been recommending 87 since the beginning of time.


True, but they want to sell a economy car it wouldn't be good if they recommended Higher Octane.
A lot of research is suggesting that the 1.4 LE2 Turbo would respond well to high octane better MPG and Power. 
Sure they can adjust the timing and such for low octane so they can advertise as so.
Just a though I'm no expert that's why I'm asking the question..


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## HBCRUZE2017 (Jan 25, 2018)

87 for my cruze 91 for my camaro ss lol


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## snowwy66 (Nov 5, 2017)

Quite a few are using the higher octane. As the engine is considered a high compression engine. Some believe it might also be the cause of the dreaded piston failure by not using higher octane. I don't know if anything has been confirmed yet as to the cause of the problem. 

Nissan has a car. I don't remember what model but it was popular. My cousin once owned it. I believe the manual recommends 91 octane. Anything lower causes check engine light. So, she had no choice but to use 91. 

If nissan can sell a higher octane economy car. Shouldn't be any reason why the other brands couldn't do it also. And if they all jumped on board. The people wouldn't have a choice. 

Much like this auto stop crap is spreading around. Even the semi's are using it now. 

It won't be long now, before we're all dead silent at stop lights. Light goes green. And everybody is starting up going VROOM VROOM.


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## jblackburn (Apr 14, 2012)

Yes; my car responds much better on 93 octane and has substantially better and smoother low RPM power. Any time I have run less in it, it sometimes chokes in traffic and acceleration is just more inconsistent from it pulling power to avoid knock.


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## ProDigit (Aug 31, 2015)

I have a gen 1, but unless the weather gets above 90F, the difference is hardly noticeable.
Above 100F temperatures, the cruze has almost no overtaking power, and takes forever to get past 80mph.

On a gen 1, turbo lag is greater due to heat soak.
Where as below 80F, the turbo kicks in around 2k rpm, at 100F it kicks in closer to 2750rpm.
I know the gen 2 kicks in later, around 3k rpm, or so, so expect at least 500rpm higher, before the boost kicks in.

Or, get higher octane fuel in summer.


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## Cruzen18 (Jan 28, 2018)

Thought I read one of these threads (or maybe somewhere else also) that running lower octane in winter was ok, due to blend composition, but to switch to higher octane for summer?


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## obermd (Mar 3, 2012)

Cruzen18 said:


> Thought I read one of these threads (or maybe somewhere else also) that running lower octane in winter was ok, due to blend composition, but to switch to higher octane for summer?


Gasoline octane is a measure of resistance to pre-ignition, which causes pinging and knock. Gasoline is less likely to do this in colder weather so the octane requirements aren't quite as high. The key here is the fuel itself is colder when it gets to the cylinder (ignition chamber).


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## snowwy66 (Nov 5, 2017)

Air is also thicker when cold.


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## jblackburn (Apr 14, 2012)

> The key here is the fuel itself is colder when it gets to the cylinder (ignition chamber).


And intake air temps are far lower as well, which means less of a chance for pre-ignition. 

The intercooler can only cool intake air closer to ambient temp. So, when ambient temp is 90+F...the intake air temps are quite high in the summer, especially with A/C blasting and the turbo boosting away.  

While my Gen 1 was ok to fall back on 89 in the winter with, the Gen 2 seems to still hate it in cold temps.


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## Cruzen18 (Jan 28, 2018)

jblackburn said:


> While my Gen 1 was ok to fall back on 89 in the winter with, the Gen 2 seems to still hate it in cold temps.


I know all cars are their own creatures, but I've been running the lower octane in mine since I got it in Jan (and confirmed with dealer who has the same car) and not had any issues with mine.


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## jblackburn (Apr 14, 2012)

Cruzen18 said:


> I know all cars are their own creatures, but I've been running the lower octane in mine since I got it in Jan (and confirmed with dealer who has the same car) and not had any issues with mine.


Entirely possible they've improved the ECU tuning since 2016 as well...mine was the first year for the new design. They did improve the Gen 1's tuning every year or two.


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## WorldCruzer (Jan 16, 2017)

jblackburn said:


> While my Gen 1 was ok to fall back on 89 in the winter with, the Gen 2 seems to still hate it in cold temps.


I ran only 87 in my '16 gen 1 (it was a lease) and I never noticed/had any major issues through the year I had it (24k miles) 

In my '16.5 gen 2 (which i bought in Jan of '17 in MI...think COLD) I started with 87 and then ran a couple tanks of 93 while driving about 100+ mi/day of mostly highway. My car just seems to love it more than 87 even with the cold temps. Pretty much whats already been stated, but I noticed much smoother acceleration especially on the lower end, and I consistently gained about 2-3 mpg according to the DIC. Have only used 92/93 in it since then.


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## Allport (Jan 16, 2017)

My 2017 gets shell 89 only. I've run 87 and 91. I only run shell and nothing else. Car was a bag of crap on the 87 Irving when I bought it new. Burned that as fast as possible and went to shell 87. Much better. Then went to 89 and then 91. Can't tell a difference between 89 or 91 in power or mileage.


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## Cruzeeco2011 (Jan 27, 2016)

Turbo plus high octane will give you more power more response, les knock, and if you dont get into boost will probably help your fuel economy, turgo cars love high octane.

Your car its gas direct injected so it dosent need 92 octane, however if you love your car to run better and if you want to keep your engine healty for a loong long time go with 92 octane.


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## jblackburn (Apr 14, 2012)

Cruzeeco2011 said:


> Turbo plus high octane will give you more power more response, les knock, and if you dont get into boost will probably help your fuel economy, turgo cars love high octane.
> 
> Your car its gas direct injected so it dosent need 92 octane, however if you love your car to run better and if you want to keep your engine healty for a loong long time go with 92 octane.


Thought the DI would be better with low octsne, but more power density, so it isn't. 

Sent from my SM-G950U using Tapatalk


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## Premier17 (May 20, 2017)

When I bought my Premier the dealer filled my tank completely with 87 Octane gas. I can tell you, that I couldn't wait to get rid of that tank and move on to running Premium. The car runs much smoother with 93 Octane and that's all I'll ever run in it. I noticed a large bump in gas mileage too after switching to Premium so it makes up the difference I feel.


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## Slimgravy (Nov 12, 2017)

Again with the 87 vs 93... So, for the last whole tank of 87 I have been watching the knock retard graph in torque. With 87 and my 25 Mile drive home from work id see at least 50 to 60 instances of KR. Mostly 1° but it was always hitting KR. Even coasting to a stop. It would hold 5° if I ran it up, higher rpms really set it off. Some of the worst was general in town driving with it in D. Putting it in L5 it was better, but still had lots of activity.

Now I ran all the 87 out and put in 12.3 gal of 93. Drove it for 40 miles to make sure it was all 93. Now on same drive home of 25 miles I only got 2 small blips. One 1.5° and one .5°. 
Lugging it in 6th gear was perfect as was the high rpm pull. Not one blip. The 2 that did show was during a 3-4 shift and 18psi.

I been looking for something to justify ¢.60 a gallon diff in gas, I may have found it. If it keeps my car out of warranty repairs, I'm in. My beemer needed 93 so I'm used to the higher cost.


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## llbanks522 (Nov 23, 2017)

Slimgravy said:


> Again with the 87 vs 93... So, for the last whole tank of 87 I have been watching the knock retard graph in torque. With 87 and my 25 Mile drive home from work id see at least 50 to 60 instances of KR. Mostly 1° but it was always hitting KR. Even coasting to a stop. It would hold 5° if I ran it up, higher rpms really set it off. Some of the worst was general in town driving with it in D. Putting it in L5 it was better, but still had lots of activity.


Is there some kind of electronic device that allows you to follow this? How expensive is it? I do 75% of my driving around town.


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## Slimgravy (Nov 12, 2017)

Yes... torque pro app.. it was 5$ and I use a $10 bluetooth obd2 dongle. I set the time graph for the KR as it happens fast and doing this I can see it better.


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## llbanks522 (Nov 23, 2017)

slimgravy said:


> yes... Torque pro app.. It was 5$ and i use a $10 bluetooth obd2 dongle. I set the time graph for the kr as it happens fast and doing this i can see it better.


thanks! ?


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## Heretic (Apr 25, 2018)

Since I got my 2017 Premier in late April, I've only filled it up twice and both times were with 93-octane BP (BP 93-octane used to be the Amoco Gold Label brew back in the day before BP bought Amoco. Amoco Ultimate I believe it was called, and it had somewhat of a reputation as being the purest, cleanest gasoline available.) 

I have no idea what the dealer filled it up with, but I'd bet it must have been 87-octane because the little turbo seems to me to be more agile off-the-line as the original gasoline gives way to the 93-octane. I imagine as the weather warms a difference between the two will be even more noticeable. 

I was in stop-and-go traffic this afternoon, noticing what a crappy job GM engineers did with the shift points on that 6-speed auto tranny. I noticed several times when the tranny up-shifted WAY too soon and dumped the RPMs way too low as it was pulling away from a stop, causing the car to lug. NOT good! Lugging causes engine failure and is, no doubt, at the heart of that little motor's piston-slinging ways. 

I know the reason why the tranny is programmed that way, but it ticks me off every time I think about the gooberment being in our business so much we can't even tune our vehicles to run properly. It may just be my imagination, but the car is a joy to drive "spiritidly" with 93-octane fuel.


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## Ecotecrican (May 26, 2018)

I have a gen2 and i only run shell vpower+ 93 or bp 93. It runs alot smoother and a lil quicker too. Its feels sluggish on 87 compared to using 93. My wife has a gen1 and she uses Sunoco 89. She noticed the difference just running 89 compared to 87. Oh and both gen1 and gen2 we see better mpg also.


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