What kind of fuel do i use for the hemi 5.7?
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What kind of fuel do i use for the hemi 5.7?
I was looking in the manual and it says 89 fuel is to be used with the hemi. I have been using the 87 is that hurting performance and what not. I know this is a newbie question.
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RE: What kind of fuel do i use for the hemi 5.7?
The manual recommends 89 but says 87 is acceptable. If it isn't pinging use the 87. I have only put the 87 in it, even in 100 degree weather without any detonation.
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RE: What kind of fuel do i use for the hemi 5.7?
If you are not familiar with the "pinging" noise and are still concerned, any good shop can scan your PCM (computer) for KR. KR is "Knock Retard" or how may degrees of retard your motor is needing to accommodate the lower octane gas.. The computer is able to adjust some for the lower octane gas..
Admin formally known as 94rt10ohio
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From: Curtice, OH
RE: What kind of fuel do i use for the hemi 5.7?
ORIGINAL: twiztidz
I was looking in the manual and it says 89 fuel is to be used with the hemi. I have been using the 87 is that hurting performance and what not. I know this is a newbie question.
I was looking in the manual and it says 89 fuel is to be used with the hemi. I have been using the 87 is that hurting performance and what not. I know this is a newbie question.
Look at it this way. DC recommends 89. 89 will cost you an additional .10 on average, or 2.60 per tank. Worst case I can imagine is filling up once a week, which I think is extreme, when I did drive mine daily I could get 10 days out of it. That would be just over $130 a year (weekly fill) you would be saving by not running the recommended. Is it worth it? I would say for $2.60 a tank get the recommended. Run 89.
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RE: What kind of fuel do i use for the hemi 5.7?
ORIGINAL: 94rt10ohio
I run 89, changing to 91/93 in the summer as I will have some programming done that will require it.
I run 89, changing to 91/93 in the summer as I will have some programming done that will require it.
Who told you a new program requires a higher octane?
Does the programming advance the timing so much that a higher octane is required?
Save your money and run 87 there is absolutely no advantage to a higher octane, especially a 93.
I drove up mount washington, towed a boat way too big for my truck in 100 degree weather and just generally pound on my truck everyday. Never had a ping on 87.
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RE: What kind of fuel do i use for the hemi 5.7?
ORIGINAL: HemiBuell
I am pretty sure this is false. The higher octane number just prevents detonation. Gas is supposed to burn in your engine not explode. I was told by a very succesful engine bulder that a higher compression ratio or a hotter air/fuel mixture are the only reasons to run a higher octane.
Who told you a new program requires a higher octane?
Does the programming advance the timing so much that a higher octane is required?
Save your money and run 87 there is absolutely no advantage to a higher octane, especially a 93.
I drove up mount washington, towed a boat way too big for my truck in 100 degree weather and just generally pound on my truck everyday. Never had a ping on 87.
ORIGINAL: 94rt10ohio
I run 89, changing to 91/93 in the summer as I will have some programming done that will require it.
I run 89, changing to 91/93 in the summer as I will have some programming done that will require it.
Who told you a new program requires a higher octane?
Does the programming advance the timing so much that a higher octane is required?
Save your money and run 87 there is absolutely no advantage to a higher octane, especially a 93.
I drove up mount washington, towed a boat way too big for my truck in 100 degree weather and just generally pound on my truck everyday. Never had a ping on 87.
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Admin formally known as 94rt10ohio
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From: Curtice, OH
RE: What kind of fuel do i use for the hemi 5.7?
ORIGINAL: wreckless123
Yes programming DOES require higher octane. When you buy a programmer you have a few different programs that are created with different octane ratings in mind..
ORIGINAL: HemiBuell
I am pretty sure this is false. The higher octane number just prevents detonation. Gas is supposed to burn in your engine not explode. I was told by a very succesful engine bulder that a higher compression ratio or a hotter air/fuel mixture are the only reasons to run a higher octane.
Who told you a new program requires a higher octane?
Does the programming advance the timing so much that a higher octane is required?
Save your money and run 87 there is absolutely no advantage to a higher octane, especially a 93.
I drove up mount washington, towed a boat way too big for my truck in 100 degree weather and just generally pound on my truck everyday. Never had a ping on 87.
ORIGINAL: 94rt10ohio
I run 89, changing to 91/93 in the summer as I will have some programming done that will require it.
I run 89, changing to 91/93 in the summer as I will have some programming done that will require it.
Who told you a new program requires a higher octane?
Does the programming advance the timing so much that a higher octane is required?
Save your money and run 87 there is absolutely no advantage to a higher octane, especially a 93.
I drove up mount washington, towed a boat way too big for my truck in 100 degree weather and just generally pound on my truck everyday. Never had a ping on 87.
Now, another thing to consider. Many new cars will say 87 is OK but 89 is best for optimal performance. The computer can actually adjust your timing for lower grades of gas, resulting in less power.
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Joined: May 2005
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From: Fort Lauderdale, FL
RE: What kind of fuel do i use for the hemi 5.7?
I don't know about ya'll, but my '03 gets a hell of a lot better mileage running 93 octane than it does running 87 octane. For the first 6 months that I owned the truck (got it used in April '05) I was using 87. I was averaging about 9-10mpg city, and maybe 12mpg highway. I then tried 93 octane. My mpg went up to approx 12-13 city, and 14-15 hwy.
I didn't have any problems running the lower octane besides crappy mileage. I didn't do anything other than using 93 octane to get the better mileage. No different gas stations (whatever is nearby when I need gas), or anything. It works for me, so I'll stick to it.
I didn't have any problems running the lower octane besides crappy mileage. I didn't do anything other than using 93 octane to get the better mileage. No different gas stations (whatever is nearby when I need gas), or anything. It works for me, so I'll stick to it.
