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Discussion Starter #1
I was perusing some of the older posts from the performance part of this forum and ran across one that said to use 93 octane and one that said to use 91 octane. I just use your basic regular gas. Not sure what octane. What is the best for 2.4 base or is it no big deal? Every car I have ever had I just put in the regular, push the button on the extreme left and call it good. Will a higher octane hurt anything? I mean its a Sky. Not that exotic.
 

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There are LOTS of discussions or more likely arguments on this topic! GM recommends 91 for the 2.4L. Why? Because the compression ratio is a bit on the high side at 10.5:1. Using lower octane may result in some pinging and/or reduce mpg's. Pinging can damage the engine over time. If you are at high altitude such as Denver where the air is thinner then a lower octane can be used just fine.

While the engines computer may retard or advance timing to adjust for different octanes, the effect is often lower mpg and lower performance if too low of octane is used.

The Redline 2.0L has a compression ration of 9.2:1. However, being turbo'd the effective compression ratio is much higher. With only 5PSI boost the effective ratio would be 12.33:1.

In my opinion premium should be used for both.
 

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I was perusing some of the older posts from the performance part of this forum and ran across one that said to use 93 octane and one that said to use 91 octane. I just use your basic regular gas. Not sure what octane. What is the best for 2.4 base or is it no big deal? Every car I have ever had I just put in the regular, push the button on the extreme left and call it good. Will a higher octane hurt anything? I mean its a Sky. Not that exotic.
:jm2c: Because you operate your SKY 2.4 at only a few feet above sea level, I would recommend 91 octane as a gesture of love for your car.
 

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Discussion Starter #5
Ok, now you can put the dunce cap on me and sit me in the corner after this one. 89 vs 91 octane. Is there enough change there to make a difference. Sorry. It's hell being the slow kid in class.
 

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Ok, now you can put the dunce cap on me and sit me in the corner after this one. 89 vs 91 octane. Is there enough change there to make a difference. Sorry. It's hell being the slow kid in class.
I really doubt that you will notice a difference unless you pedal to the metal. However, your car will love you for it if you use 91.
 

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Discussion Starter #9
Ok, here's my pride and joy and my Sky too.
 

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Discussion Starter #11
I have loved the design and lines of the Sky since I first saw one years ago and when the bucks and price and color came together last month, I had to have it. I had no clue what to look for and missed some, now, obvious things I should have seen. Nothing major and with the help of the Sky addicts on this forum, I am getting on top of them. Finding and fixing stuff has really helped me learn a lot about this car. I plan to keep her for a long time.
 

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Discussion Starter #13
I have not got there yet. I am learning as I go here and sometimes, I find, there are options you guys employ that are a bit different than what the manual says just thru experience. Just going to the people that know for opinions.
 

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I can't speak for sea level, but at 1000 feet the 2.4 runs exactly the same with all grades of fuel, and the (un-tuned) RL runs the same on 91 as it does at 93.
I did an extensive series of tests using a G-Tech and a DashDAQ and found no difference in performance with the fuels indicated.

The owner's manual recommends a higher grade of fuel than is required in order to provide a buffer in case of extreme conditions.
I think that the consistent use of top-tier fuel is more important than the grade of fuel used, and I use Shell 89 in the 2.4 and 91 in the RL.
This works well for me and I am comfortable with it, but other opinions are certainly just as valid.
 

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The price of fuel is going up. Notice the difference since Harvey and Imra strolled on through? With the shut down of several refineries in the Gulf, it could be sometime before the prices come down again for the American consumer.

$$$ comes down to what you can afford to put in? Yes I agree with the other owners here, that Top tier fuels Level 1 is the key. IF you can only afford a low tier fuel, non branded then you get what you pay for. You can boost the octane level with additives, but that lasts for a tank full maybe two if your lucky.

It's almost that time of year when the major Oil Co. change over the formula's for the winter season. Well in winter we don't really drive the Kappa, except in some states that don't have a winter.... per say. You can do this too... $10. of 89, $10 of 91 or $10 of 91 & 93 if available in your area?
$ 10 for Fun $20 to Run & $ 40 to fill it give or take but put good quality fuel in it, and your Kappa will thank you in multi versions of the Permagrin mode as possible on the Permagrin scale.. if there is one? Robo will have some sort of table measuring this somewhere.. lol.

I not sure of the previous owner who had my car before, but since I have owned it I have used Shell 93 every time. No worries.. no knock or ping ever.
Price per gal. at last fill up was $3.27 per for 93 at my local station last week? This week... arm and a leg for sure.

LAC
 

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Discussion Starter #16
I usually go to Pilot or 7-11 for fuel and use basic regular, because they are way close. Sounds like the Shell or Mobile station and mid grade would be the wiser choice
 

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and I use Shell 89 in the 2.4 and 91 in the RL.
I'm in Phoenix which is at 1,100' elevation. Fuel here is 87,89 or 91. A friends 2.4L tends to ping a bit when using 87 so he uses 91. It might run fine with 89. My own feeling is that any engine with a 10.5:1 compression ratio would do better with 89 or 91 in the long run. This could be better mpg or just better engine longevity if light pinging occurs that is not detected by the driver.

I buy gas at Costco which only has 87 or 91 which is often 20 to 50 cents cheaper than other stations. If midgrade 89 is desired I could mix the two but bit of a pain and savings isn't much.
 

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I decided that my feelings weren't accurate enough, so I did a series of tests with each grade of fuel in my 2.4. I record fuel used and mileage all of the time, so that part was easy. I was running 89 before I started, switched to 91 for two tanks, then to 93 for two tanks over a six-week period in the spring. When travel season ended in the fall I started at 93 and repeated the process back to 89. I ran the tank below 1/4 each time to minimize fuel mixing, and I used the same pump at the same station each time. My driving was as consistent as I could make it throughout the tests, but it was real-world, so there were some variations.

The first tank in each direction resulted in slightly better mileage, but it went back to the original value for the second. All grades of fuel gave essentially the same result.

Midway through the second tank I did controlled acceleration runs using the G-Tech. The G-Tech isn't perfect, but it is certainly better than seat-of-the-pants and its results are very consistent. All grades of fuel gave essentially the same result.

I used the DashDAQ to look at ignition timing to see if there was any knock compensation. There wasn't any and all grades of fuel gave essentially the same result.

I can't say anything definitive about long-term damage because the 2.4 only has 105k miles on it, but so far it seems OK.

The bottom line is that for my cars, and my driving style, in this area, using the fuel that I buy, 89 octane Shell works fine in the 2.4, and 91 works fine in the RL.
 

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I usually go to Pilot or 7-11 for fuel and use basic regular, because they are way close. Sounds like the Shell or Mobile station and mid grade would be the wiser choice
Something to consider:
In our area I get fuel at WaWa because they have the newest tanks.
 

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I know we have had this conversation before here on the forum. What octane? What oil? What tires? With new owners popping up everyday in the kappa community of permagrin . Gas is gas.. put in fossil fuels, turn key, drive it like you stole it. Not so fast....

I knew I had read JohnWR quote about his tests done earlier somewhere before on here. Took awhile for the ole grey matter to kick in.
What's in name? Exxon Shell Mobil Sunoco BP take your pick. Sometimes its all the same refined gas, in the same tanks, from the same refinery, just a different tanker truck pulling up to it. Different costs, different distributors, different locations... but in the end same sh*t, from the same pump.

7-11 and or Pilot could be one and the same here, as far as the tanker truck and distributors, depends on who or where the corporate big whigs and bean counters buy from. Wawa could be worse, if ""Joe Blows distribution " network and refined in our own backyard distillery... has anything to do with it?

It's all about location, in the real estate world. Same with us humans. We are creatures of habit. I always go there. I only buy from that store. We return to what is easiest or most comfortable for us, in the time of need. I need fuel to continue the permagrin status for today. Where you live, what is offered to you in that location, for your needs... why should I go out of my comfort zone, just to so I can get more power to my car. Try it I say. Can't hurt any... change to a different brand, just once maybe twice if you like it twss.. really in the end it shouldn't matter unless your having a real problem. What is important to you the most here? Cost? Location and ease of access? Mpg? Bang for my buck?

New tanks in the ground... 20,000 gallons worth. Yes new equipment is a good thing, I used to work in the petroleum business selling and servicing parts. A dirty fuel filter is never a good thing, in your car or the pump at which you use so frequently, they can only filter so much sludge from the bottom of the tanks, before it goes into your car. Change the filters on the pumps themselves is not done on a regular basis, only when there IS a problem with that pump. Trust me on this one. Never ever fill your tank, when a tanker is there stirring up all kinds of crap in the tanks below ground. Drive away to a new location, out of your comfort zone, just this once... and your Kappa will smile like you do all the time.

LAC
 
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