Thread: 91 octane benefits in N/A 3800?

I had the overkill 91 octane tune on my GT last year and it suppose to add some power but my car ran excellent with the tune plus I had full bolt ons.

I feel like my car is a little more spunky when it's running 93. Whether it's just a placebo effect or not, I've never been able to test.

i have the supercharger. i bought the car about 2 months ago from a girl who used 87. it ran like a champ. i put 93 in it (the two stations i can find anything higher than 91) and runs the same as far as I can tell. same mpg. i've put 4 or 5 tanks in it now and used seafoam in the first tank. i can't tell any difference.

maybe i'm just lucky, though.

i put 91 in my 89 regal 3.1L. made no difference at all.

Originally Posted by Shiftingshaddow

i have the supercharger. i bought the car about 2 months ago from a girl who used 87. it ran like a champ. i put 93 in it (the two stations i can find anything higher than 91) and runs the same as far as I can tell. same mpg. i've put 4 or 5 tanks in it now and used seafoam in the first tank. i can't tell any difference.

maybe i'm just lucky, though.

i put 91 in my 89 regal 3.1L. made no difference at all.

i got my 04 from the dealer and immediatly noticed it has 87 in it when i test drove, i went to the gas station and filled up with 93 cus it was basicly empty and as i was driving(my dad was in the car and heard it too) you could hear and feel the 93 kicking in. The car started running so much smoother and had more of a roar to it.

Our pcms sense what octane gas we are burning and run accordingly unless obv tuned otherwise. So you would def see gains from 93, i would try a tune up, replace pvc clean maf wire plugs fuel filter air filter ect.

Originally Posted by Grimsin

And for the supercharged guy I hope you know you HAVE TO run atleast 91.

yeah. i know. i was saying previous owner ran it on 87. it seems to have little or no effect. she apparantly wasn't hot rodding it around.

Originally Posted by Grimsin

For all you n/a guy's without a tune running on 91 it wasting your money

Couldn't agree more.

Originally Posted by smoke14

Couldn't agree more.

disagree....Girlfriend has a malibu and my sister has a G6 both with the 3.5L. scanned both on 87 and seen 7-9*kr filled em both with 93 and rescanned 0* across the board . While its not as beneficial as it would be with a tune, it still helps

Originally Posted by djrepoman

disagree....Girlfriend has a malibu and my sister has a G6 both with the 3.5L. scanned both on 87 and seen 7-9*kr filled em both with 93 and rescanned 0* across the board . While its not as beneficial as it would be with a tune, it still helps

Yes in cases such as that (where you see a lot of KR), 93 would be benificial and you WILL see performance gains because the computer wouldn't have to pull timing.

Otherwise, putting premium in an N/A is pretty much worthless. And it WILL decrease your gas mileage.

Originally Posted by djrepoman

disagree....Girlfriend has a malibu and my sister has a G6 both with the 3.5L. scanned both on 87 and seen 7-9*kr filled em both with 93 and rescanned 0* across the board . While its not as beneficial as it would be with a tune, it still helps

That's a 3.5L not a 3800. Either way, kinda a waist of money . I still agree with blueguy and Grimsin.

Originally Posted by Grimsin

For all you n/a guy's without a tune running on 91 it wasting your money,.

This.

Most people still don't understand what octane does.

Octane is NOT a power adder.
Higher octane does NOT burn cleaner than lower octane from the same place.
Running more octane than necessary will HURT gas mileage.

It really depends on the car. The 04+ cars definately benefit from it because they had a lot of extra timing and would knock easily on 87. Using higher octane reduces some of the knock and gives you more power.

When I filled up last friday I put in a tank of 93. I just filled up this morning and got 18.6 MPG vs the basement 17's I normally get. My driving style didn't change at all from normal, in fact there were probably a couple of extra WOT pulls in there to see if the high octane made a difference. I wonder if it's a coincidence.

We had this thread last week: http://www.grandprixforums.net/91-oc...bad-75738.html

I always run 93 octane in the Gtp. Always.

Depending on the amount of ethanol content in the fuel (its different everywhere), A higher octane rating can decrease your gas mileage.