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93 In 5.7L?

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Can a 5.7L R/T take 93 octane gas?
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2015 RT 5.7 M6
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5.7 manuals require 91 minimum
5.7 autos require 89 minimum (87 acceptable)

That said, 93 octane will help prevent pre-ignition which usually happens on hot days when you are running the engine hard. The engine detects pre-ignition using knock sensors. When knock is detected the PCM removes timing (reduction in time means less power being developed). So if you are not seeing much knock with 89 octane then no reason to go any higher.
 

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5.7 manuals require 91 minimum
5.7 autos require 89 minimum (87 acceptable)

That said, 93 octane will help prevent pre-ignition which usually happens on hot days when you are running the engine hard. The engine detects pre-ignition using knock sensors. When knock is detected the PCM removes timing (reduction in time means less power being developed). So if you are not seeing much knock with 89 octane then no reason to go any higher.
you can or you can make your knock sensors less sensitive.
 

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From Sea Level to about 2000 ft elevation, 93 Octane gas will be fine. 2000-3500 ft and 91 is about the same as 93. 3500-5000 ft 89 should be good. According to your manual, 87 is not recommended for long term use. The ANN will automatically adapt to it so no tuning is needed.
 

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From Sea Level to about 2000 ft elevation, 93 Octane gas will be fine. 2000-3500 ft and 91 is about the same as 93. 3500-5000 ft 89 should be good. According to your manual, 87 is not recommended for long term use. The ANN will automatically adapt to it so no tuning is needed.
That is not correct. 87 is acceptable on a 5.7 auto. Running 93 octane on a 5.7 auto is overkill unless you want to ensure little to no knock is experienced. I used to run 93 on my 2013 5.7 JGC and between 87 and 93 there was noticeable less fish bite feel (happens when PCM detects knock and pulls timing) when accelerating hard on a hot summer day or towing the boat.

 

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I have an 05 Ram, auto and have used 87 Octane from day 1. I now have 98,000 miles and never any knock or problems. My son in law tried 89 and saw no difference in gas mileage so why spend more $ if not needed.
 

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You run 87 long enough the PCM will store long term knock and pull timing automatically to avoid knock. You can reset adaptives by disconnecting the battery or pulling the PCM fuse. I have shown the amount of knock retard (6 degrees on average) my 2013 JGC 5.7 would experience on a hot summer day running 87 octane. When I fill up with higher octane fuel I usually reset my adaptives so PCM starts off with long term knock reset.
 

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Have driven my six-speed 5.7 on 89 for ten years with no issues. I only recently learned that the manual called for 91. The salesman had told me 89 and I guess when I read the manual myself I missed that.
 

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Can a 5.7L R/T take 93 octane gas?
Your not gonna gain anything but wallet burn, 89 is fine and if you can go with Non Ethanol...
Anything Higher no benefit on a total stock setup.
(y)

Nick.DeConto I don't even run 93 in my Redeye, I run 90 octane non-ethanol fuel.

It runs so much smoother and 98% of the Black nasty soot on the tail pipe tips is eliminated along with the 2nd to 3rd gear burping/gurgling is gone.
 

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How so with the knock sensor? resistor?
No, by changing the voltage tables in the tune.

Most people swear they don't feel a difference between 87 and 91 probably because their butt only detects the thickness of their wallet but do a log of long and short term knock in the summer and see how much timing is pulled. Every degree is worth maybe a couple of ponies.
 
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