With t he price of gas soaring around here, which octane do you use in the 5.7lL Hemi? The 87 octane is about 11 cents cheaper here with 89 pussing $3 a gal. The manual recommends 89, but also states it will pass emisions with 87-89 octane.

 

Do what your heart tells you. If the experts say 89 that's what I could use besides, you save a whole 2 dollars on a full tank of gas when using 87 instead of 89. Hardly seems worth it to me.

 

Oh yeah, it would really suck to go in for some sort of engine warranty repair and hear them say, you've been using 87 instead of 89, your warranty is void, have a nive day.

 

They can not void the warraty for that.The owners manual says87 is OK with 89 recommended.

With that said I run 89 in the Hemi

 

I use 91 or 93 with the Superchips, do you think that willcause any problems, using the higher then recommended octane? I don't think that it will since you are using a better quality fuel but I would like to hear some input... that and using the 87 with the superchips economy setting.

 

Using the higher octane is fine(91+), just not worth it if you are running stock. If you have a tuner, great, but you won't harm the engine by running higher octane even without it. Higher octane means nothing more then the gasolines ability to compress before it ignites on it's own. That's why our manual states use 87, then if your eng knocks, up it to 89. The higher the octane the the more it can be compressed. It has no other properties. It exists for high-compression ratio cars light sports cars, modded hemis, etc. It contains nothing else that will do any good for your car like detergents or additives. As a matter of fact, it may be better to buy a "quality" 87 gas, then a "budget" 91 gas because of the quality of the gas. About 15 years ago in Cali it was proven that am/pm gas had more "crap" in it then any other brand, but that was why it was cheaper. Who knows now-a-days?

 

As already stated, the cost difference between 87 and 89 octane gas is .11 cents a gallon. That works out to only $2.42 more if you put in 22 gallons of the 89 octane. For that little difference, I would run the 89 like the manual recommends. Red

 

That's my point, if doesn't need it, why even waste the $2.42? Would you drive across the street to save .05? You know you would, why not? That's only half the savings.

 

I always run kwik trip 89 octane. And the fact that its only 2 cents a gallon more here doesnt hurt my decision any either.

 

do any of you use an octane booster say on the 87 grade ? was thinking about doing this....didn't know if there would be any advantages/disadvantages. (?) its usually only $1 or 2 for a bottle.