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89/90 Octane?

  • Thread starter Thread starter 92Frankenstein
  • Start date Start date May 5, 2004
9

92Frankenstein

New Member
Apr 25, 2004
223
0
0
Minnesota
May 5, 2004
#1
  • May 5, 2004
  • #1
I know I have ran 93 and it does nothing at all.. I usually only run 86/87 octane, but I was curious if i would get better mileage with 89/90 octane? anyone else run this? I would be glad to know, thank you.
 

bhuff30

Founding Member
Dec 11, 2001
6,037
35
129
Olathe KS
May 5, 2004
#2
  • May 5, 2004
  • #2
It won't make a difference unless you have a problem with detonation, and on your car, you shouldn't have any problems at all with that.
Ironically, lower octane gasoline actaully has more engergy in it, so you could theoretically get better gas milage with it.
 

jbtelfer

New Member
May 3, 2004
23
0
0
Winnipeg, MB Canada
May 5, 2004
#3
  • May 5, 2004
  • #3
My understanding about octane is basicly higher octane prevents detonation and if your not having detonation problems then the lower octane is fine... and with gas prices the way they are now save your money. Now if your increasing your combustion chamber pressure ie higher compression, turbo etc, then you will need higher octane.

Thats my opinion anyway if im wrong someone please let me know but thats how it was explained to me in school. I'm an aircraft mechanic.
 
K

ka0tyk

Founding Member
Oct 10, 2001
1,610
0
0
Los Angeles, CA
May 6, 2004
#4
  • May 6, 2004
  • #4
unless you're running high compression or have your timing pumped up around 15+ then theres absolutely no need for high octane and in some cases you CAN have higher MPG with the correct octane gas.
 

Bearded Forever

Type O Danzigative the Dark
Founding Member
Sep 4, 2000
4,927
3
98
Vinland
May 6, 2004
#5
  • May 6, 2004
  • #5
Back when I first got my car in 2000 I tried 87 VS 93 and I lost about 3 mpg using 93.
 
1

140cilx

Founding Member
Sep 7, 2001
2,385
0
0
GA
May 6, 2004
#6
  • May 6, 2004
  • #6
Run the lowest octane your car can handle. The higher the octane, the slower the burn, the lower the energy output is. High octane is necessary for high compression and boost applications to help with pre-detonation.
If your n/a requires mid or hi octane, do a radiator flush and put in a 180 degree thermostat and tuneup. This should allow you to go back to regular unleaded.
 

Lex

Founding Member
Mar 2, 2004
248
0
16
Halifax NS. Canada
May 6, 2004
#7
  • May 6, 2004
  • #7
This is defintely a confusing subject. I was told so many times to use high octane (to get better miliage) and now to use low octane. Perhaps this was from people who owned turbos Anyways Judging by the experts here I will lower the octane and see what happens. You guys helped me out in so many ways, I almost swear by Stangnet now
 
L

lxturbo

New Member
Mar 26, 2004
17
0
0
May 6, 2004
#8
  • May 6, 2004
  • #8
Dude.
High octane is good for one thing.COMPRESSION!! If you are not having detonation problems, do not bother and in some cases it will hurt performance on a lower compression motor by slowing the burn down too much!!
 
9

91_4ourBanger

New Member
Feb 8, 2004
255
0
0
May 8, 2004
#9
  • May 8, 2004
  • #9
isnt higher octane gas usually cleaner too???? so your fuel filter wont be clogged up as easily?
 

nomuffler

Member
Aug 20, 2003
330
0
16
Awash in a sea of decedant luxury and meaningless
May 8, 2004
#10
  • May 8, 2004
  • #10
Run the regular, it don't make no difference with a simple stock engine. I can't imagine gas being at different levels of cleanliness, I mean why would they clean the premium more than the regular? Maybe they achieve a higher octane by isolating the combustible material more and that gets interprited as cleaner?
 

bhuff30

Founding Member
Dec 11, 2001
6,037
35
129
Olathe KS
May 8, 2004
#11
  • May 8, 2004
  • #11
no difference in how clean the gas is.
What can make a difference is when and where you buy your gas. If you buy gas right after the truck comes, all the debris in their underground tank has been mixed up, and hasn't settled to the bottom yet. Also, older gas stations ussually have more debris in the tank.
So if you want good gas, buy from one of the newer stations and don't fill up right after the truck has come.
 
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