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Any benefit to using 91 Octane as opposed to 87 on Hemi
Record Breaker
Joined: Mar 2006
Posts: 2,165
Likes: 2
From: Alberta
Every hemi made is not created equal, all engines are with in chryslers specs, but no where close to being tunned for the best performance and mileage.
Run 91 octane on a cool night, or tow a heavy load during the day and hands down 91 octane will net you a increase in mileage and h/p, over 87 octane in identical conditions..
87 octane is buying you trouble over the life of your engine, ya it burns real nice with carbon build up and fouling up the throtle body.
I run 89 for point a to b, towing or highway, I run 91.
Over the life of the engine, you will save with 91 octane ( facter in cost's of flue injector cleaning with 87 and your spending the same as running 91 )
as for the extra cost, on a 35 gallon tank 91 gives me the performance, but I don't pay it unless I tow, or a long distance drive.
Run 91 octane on a cool night, or tow a heavy load during the day and hands down 91 octane will net you a increase in mileage and h/p, over 87 octane in identical conditions..
87 octane is buying you trouble over the life of your engine, ya it burns real nice with carbon build up and fouling up the throtle body.
I run 89 for point a to b, towing or highway, I run 91.
Over the life of the engine, you will save with 91 octane ( facter in cost's of flue injector cleaning with 87 and your spending the same as running 91 )
as for the extra cost, on a 35 gallon tank 91 gives me the performance, but I don't pay it unless I tow, or a long distance drive.
Professional
Joined: Dec 2009
Posts: 150
Likes: 0
From: Medicine Hat, Alberta
worst post ever.
Every hemi made is not created equal, all engines are with in chryslers specs, but no where close to being tunned for the best performance and mileage.
Run 91 octane on a cool night, or tow a heavy load during the day and hands down 91 octane will net you a increase in mileage and h/p, over 87 octane in identical conditions..
87 octane is buying you trouble over the life of your engine, ya it burns real nice with carbon build up and fouling up the throtle body.
I run 89 for point a to b, towing or highway, I run 91.
Over the life of the engine, you will save with 91 octane ( facter in cost's of flue injector cleaning with 87 and your spending the same as running 91 )
as for the extra cost, on a 35 gallon tank 91 gives me the performance, but I don't pay it unless I tow, or a long distance drive.
Run 91 octane on a cool night, or tow a heavy load during the day and hands down 91 octane will net you a increase in mileage and h/p, over 87 octane in identical conditions..
87 octane is buying you trouble over the life of your engine, ya it burns real nice with carbon build up and fouling up the throtle body.
I run 89 for point a to b, towing or highway, I run 91.
Over the life of the engine, you will save with 91 octane ( facter in cost's of flue injector cleaning with 87 and your spending the same as running 91 )
as for the extra cost, on a 35 gallon tank 91 gives me the performance, but I don't pay it unless I tow, or a long distance drive.
Professional
Joined: Feb 2010
Posts: 101
Likes: 0
From: Dayton, OH
Since 93 is always 20 cents more than 87, I buy the good stuff when gas gets expensive. If reg was $1.00 per gallon, then 93 would cost 20% premium. When gas is $3.00 per gallon, it's only like a 7% premium! What a deal!
Record Breaker
Joined: Jan 2010
Posts: 1,400
Likes: 5
From: San Pedro, California
Run higher octane when temp is hot and towing
I run the 87 most of the time. The ECM monitors the engine and protects it so that 87 will work. But if you are towing and it is hot, run the 89 - it will help control the early detonation (pinging)
Veteran
Joined: Mar 2009
Posts: 498
Likes: 0
From: back woods of Chester County PA
390 hp rating with the recommended fuel, 89 octane. Run 87 and it just pulls a bit of timing back and you loose a some performance, probably not enough to notice though but you would see it on a dyno pull.
Rookie
Joined: Apr 2009
Posts: 64
Likes: 1
From: Gainesville, FL
In short, you run 89 you get the advertised 390hp. You run 87, the computer retards timing and you get less HP. As for carbon build up, fouling, etc there is no correlation to the octane rating. Run whichever you heart desires.
P.S. - Running anything greater than 89 octane does not improve performance with a factory tune on this truck, or any engine specifically tuned for a lower octane fuel. (aka You are wasting money)
P.S. - Running anything greater than 89 octane does not improve performance with a factory tune on this truck, or any engine specifically tuned for a lower octane fuel. (aka You are wasting money)
