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Thats what the manual says. Is there any drawbacks, besides performance, to running 87 octane? I'd sacrifice the litlle bit of performance for the savings in fuel cost if it will not harm the vehicle.

Thank you in advance.
Murunga
 

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The 5.7's are designed to run on regular unleaded fuel. It will make little if no difference going from regular to mid grade fuel. Save your money. If you are talking about the 6.1 Hemi, then you MUST use premium fuel according to the recent articles.
Hope this helps. :cool:
 

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numerous threads about this on LXforums and 300cforums.... the result....

most are running 87 octane, and no ill results... some are even seeing better fuel economy with the hemi on 87 oct..

I plan to run 87 oct. in mine unless I know I want to have some fun IE: day at a track or something....

edit: the hemi has a compression ratio of 9.6:1 so 87 oct would be fine... I would actually see those that have the V6 having to run a higher octane sooner with a 9.9:1 compression ratio on the V6

Over 10:1, I would not run anything less then midgrade

but... the above are my personal opinions... someone else might disagree with me.... but I based this on experience, and reseach... so someone would have to be very convincing for me to stray...
 

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Wow I hope that 87 is OK, 91 here his up to 2.70 a gall. but if the car doesn't like it, it will get 91.
 

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I emailed Dodge technical about 87 vs. 89. They replied 87 is ok but that mileage would be slightly better using 89. I also asked about Ethonal 85 (E85) that is getting much attention and selling about $1.86/gal. E85 is 104 octane. Dodge technical said don't use - but it is my understanding that with a fuel sensor change E85 can be used.
 

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Don't use the E85, as there are other issues, but in many Midwestern States Ethanol blends are 89 octane and usually the cheapest of the three grades.
 

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I`ll use 91, because I want to eliminate knock COMPLETELY!
 

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AZCHARGER said:
I`ll use 91, because I want to eliminate knock COMPLETELY!
with the engine design and compression ratio of the 5.7 Hemi.... the only thing you will accomplish with 91 is a lighter wallet...
 

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the only thing you will accomplish with 91 is a lighter wallet...
LOL! :lol:
 

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All cars now days and YES your new Dodge Chargers etc. etc. are included will run fine on 87 or 89 or 91 or if you have 93 octane like we do here. The computer will make the adjustment and you should never hear a ping. You will lose some horsepower ( i was told you may lose around 10 horses if you run the cheap stuff) and you'll lose some of your gas mileage. But the newer cars of the last several years will run on the cheap gas or the expensive stuff.

Car companys try to get you to use more expensive gas because this was the way they got the gas mileage printed on your window stickers.
Probally getting a cut from the gas companys too... :wink:


have fun with your car
 

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look at it this way the difference between 87 and 89 is 10 cents a gal so if you use 1000 gals it cost you 100 more so go with the 89 not worth it to use 87.
 

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Yea, if you are lucky enough to have 89. Here in the part of Co. where I live we have 85, 87, and 91.
 

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Lets not forget what a higher octane actually does. Higher octane does nothing to increase power, rather the higher an octane rating, the more resistant to burning a fuel is. Thus motors with higher compression or power adders may require a higher octane to prevent premature detonation (ping). If your car does not ping on 87 octane you are wasting your money with anything higher. The best fuel for any car is the lowest octane you can get away with while avoiding pinging, this is true with respect to both power production and wallet protection.
Incidentally, as mentioned here, I too found better fuel economy by ~2mpg on 87 octane than I did with 89.
 

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so the final verdict is 87, unless you have some spare paper to throw at 89 or 93? I've been using 93 myself simply because I assumed the Hemi would need it. Im ashamed to say I dont know much about cars.. thats why I am here.. to learn.. thanks for the $$ saving information all!!
 

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elcapitan87 said:
Lets not forget what a higher octane actually does. Higher octane does nothing to increase power, rather the higher an octane rating, the more resistant to burning a fuel is. Thus motors with higher compression or power adders may require a higher octane to prevent premature detonation (ping). If your car does not ping on 87 octane you are wasting your money with anything higher. The best fuel for any car is the lowest octane you can get away with while avoiding pinging, this is true with respect to both power production and wallet protection.
Incidentally, as mentioned here, I too found better fuel economy by ~2mpg on 87 octane than I did with 89.
Not sure if that is true, on my wifes Tahoe, gets around 2MPG less if I run 85 instead of 87. Never really tried 91 though.
 

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shrinkydinx said:
how come people say "dynoed at 400hp on 103 octane"?
they running ridiculously high compression ratios?
Likely. Old car needed higher octane fuel or leaded fuel to prevent detonation. Due equally to high compression ratios and poor combustion chamber design. Our motors have neither.
I'd bet that your typical 400hp Chevy smallblock would dyno the same at 91 octane as it would at 104 octane.
 
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