Is there a differnce in performance and gas mileage?
Nope! Gimmick. GM says to run 87 octane on these cars for a reason.
Unless you're running some form of forced induction, you don't need higher octane.
THANX, i was kinda thought that.
The only thing I can ever say from octane is a couple of times I have tried different levels. At the most I have noticed 1-2 mpg better in gas mileage from the 1 level up. However if you calculate that down to cost per gallon running the 87 octane is more cost effective. And as for performance based on 1/4 mile racing if it is improving my numbers it is below the 0.1 seconds in improvement which means yet again not worth the cost. This information is based on a 1985 Regal V6 2001 Cavalier 2200 and a 2005 Cavalier ECOTEC.
Defined Parts
no difference in gas mileage for me. other than burning a hole in my pocket. As said hight octane is needed for any forced induction or high compression ie 10.5:1
Also gas has to meet a certain industry standard with cleaning detergents, so one gas company saying it is cleaner when there is an industry standard is just a gimick. A lot of gimicks to get you to by shell vs chevron vs BP. Problem may come with the actual gas station itself not the company. SOme with rusty underground tank that have sedimentation in it etc..
Any 1-2mpg difference could be other factors did i drive less hard that when i had the 87.
2004 Grand Prix GTP (Competition Group)
SOLD-->1999 Z24 5M-#30 to register on JBO
"You can please some of the people some of the time but you can't please all the people'
all the time
I like sheetz and wawa gas
sheetz had to paint on the side of their trucks that their gas actually had detergents because their were rumors circulating that their gas didn't have any cool stuff to keep your engine clean.
The key to higher fuel mileage is a lighter foot and staying on the speedlimit.
My wife got 42 mpg once in my car on a road trip to see her parents.
I can't get anything above 38.
-Chris
I tried premium fuel once in my Noen, and I actually had a big drop, 36 mpg I got on the highway, instead of my normal 45 mpg.
My mom's Chrysler Sebring says in the owner's manual the engine is built for 87 octane, and premium fuel could be harmfull and Not to use it.
higher octane s just burn slower
was meant to drive on 87 so use 87
MY 2003 SUNFIRE 15.63@87.86mph
"A N/A ecotec is not gonna give Honda's and Mitsu's that much of a run for their
money unless their blown or bottle fed.GM is still smokin crack!"
~1QWKZ24
www.streetracing.org, 08/2001
it was designed to run on 87, But i suppose GM never figured people would modify them in any way. higher octanes do burn slower, this allows for more advanced ignition timing (which the pcm does on it's own, up to 50 degrees at WOT) the more advanced timing increases cylinder pressures which in threory creates a higher compression ratio. i got from pittsburgh to DC on 8 gallons of gas... partly because i was behind a rig all the way down 70's long @$$.
