What Octane gas do you use
 

What Octane gas do you put in your 3800 II Montes. I was told that my o2 sensor and cat went bad because of the octane and maby some of the additives used at some gas stations. I usually go to a SUNOCO and use mid 89 not reg 87 but they said i should use higher prem 93.
What do you use???

RE: What Octane gas do you use
 

i just use regular 87 octane and ive never heard of an o2 sensor goin bad becuase of octane, additives could b a problem

RE: What Octane gas do you use
 

You should be able to use 87 octane in a non-supercharged 3800 series II.
In my supercharged 3800, I prefer to use Sunoco Ultra. Which for some reason in Canada is listed as 94 octane. But I think it may be the same 93 octane the U.S. has, but with a better P.R. campaign. LOL.

RE: What Octane gas do you use
 

The Supercharged 3800 is designed to use 91 octane or higher.If you use lower octane you will run out of gas really fast. Don't know about the o2 sensor.

RE: What Octane gas do you use
 

I have a non supercharged 3800 II engine but I am going to see if it has anything to do with fuel additives but I fill up 99% of time a a sunoco but I going to try the citgo down the street it has no additives

RE: What Octane gas do you use
 

Sunoco 94 is the only gas I use on my Monte.

RE: What Octane gas do you use
 

i use Shell 93 octane


i would use sunoco 94 octane, but there arent many sunoco stations around me...there is a place near the local dragstrip that sells 102 octane

RE: What Octane gas do you use
 

Not sure about the U.S., but in Canada, Sunoco says they add "up to 10% Ethanol" to their gas.
They've done this for many years. I have always used Sunoco gas in all my cars. Except on rare occasions when a Sunoco station wasn't available.
Never had a problem with their gas, 87 octane or 94 octane. But there's always a first time.

RE: What Octane gas do you use
 

i use 93 from Amoco/BP and Shell, but not Exxon (get about 3 mpg less on Exxon for whatever reason).

I get 2 miles per gallon over the 87 octane from the same stations... so i use the 93, pays for itself :)

RE: What Octane gas do you use
 

I'm with Taz, I only use Sunoco for both my cars. Their 94 Octane is awesome!

RE: What Octane gas do you use
 

there shouldn't be any reason 87 octane would ruin the o2 sensor. i would keepusing it if i was you.if you have a NA monte it is useless to put anything more than 87 or 89 in your car. octane is the property of gas that resists engine knock(which is caused by compression among other things), so the higher it is, the more protection against knock you have.thatis why high compression race motors have to run 100 octane or more.your NA montes are designed to run on 87, due to the lowcompression ratio. i am not sure what the CR of the SC montes are, but if they are a little higher, then you should run a higher octane fuel.when i was shopping around for montes, i was always told bynumerous dealer mechanics you should run at least 91 or 93in the SC.basically you're wasting your $ if you put 93 octane in your NA montes.

RE: What Octane gas do you use
 

In a nutshell, that's pretty much what I heard too. Don't know what the compression ratios are for the SC either, but I do know the owner's manual and the sticker inside the gasoline door say "Premium Unleaded Fuel Only". Which blows when the price of gas is high.

RE: What Octane gas do you use
 

guess you guys missed my first post....

i don't knwo about your results, but those were mine.

RE: What Octane gas do you use
 

yeah cowboy6622 i saw your first post. if you got better mileage, it wasn't from the higher octane. octane has nothing to do w/ fuel economy.if you google it, my previous statements are confirmed.



http://www.gasforlessmoney.com/highe...r-gas-mileage/

http://www.wanderings.net/notebook/M...sWorthTheMoney

RE: What Octane gas do you use
 

I'm finding that octane isn't always the key to performance. On our two boosted cars, this Intimidator and the 07 Solstice GXP, they are both tuned for 93 octane, and run for crap without it. The Solstice doesn't even like 92 one little bit!
But the other 2, the 82 Olds Regency and the 99 Silverado Z71, we run 87 octane.

In ALL of the vehicles, we try to stay away from the cheap gas, and independents, which also have cheap gas. QUALITY and cleanliness is ALL important to me. I know of people running midgrade and premium because regular runs for crap in their cars. But where do they buy their gas? The CHEAP stuff stations. They spend more on gas to improve the octane rating, to offset the quality problems of the regular gas!

Case in point: We have had problems with the gas gauge sending unit in our Silverado for YEARS now. I did a complete brake overhaul on the Intimidator SS this summer, and drove the truck regularly for about 2 weeks. On my 1st fill up with it (I normally fill up at BP, or Amoco gas), the gauge started working again. I continued to use the Amoco 87 and it STILL works. An occasional glitch, but LadyT also runs Citgo or whatever in it (she can't run Shell, for whatever reason, cuz it is crap here). I fill it up with Amoco, and it works again. Also, I rarely have any problems with dirty injectors.

Point is, people spend extra for octane to compensate for crap gas, when all they really need to do is quit buying the absolute cheapest gas they can. They spend more in the end for loss in milage, and dirty injectors.

like NAPA says "BUY THE GOOD STUFF!"

RE: What Octane gas do you use
 

it's "GET THE GOOD STUFF", but thats a minor tecnicality

i think i failed to mention my car was dyno tuned on 93 octane, so it's timing and adjustments are all for 93 octane.

RE: What Octane gas do you use
 

well that makes more sense why you get bettereconomy on 93. do you put out more hp than stock then?i might have to look into that mod in the future.

RE: What Octane gas do you use
 

my original pull and my last pull showed about a 10 hp difference (to the wheels), so a little bit. i don't know if there are many tuning programs out there for your engine yet though but i haven't researched this statement, so feel free to prove me wrong.

as to the guys original question... somebody fed you some crap about octane throwing an oxygen sensor. teh only thing i can think of is if you use really cheap gas with some sludge in it alot.. and i seriously doubt that would even throw the sensor. i have heard of them just going bad though....

RE: What Octane gas do you use
 

I use 87 octane but try to only go with Shell, BP or Mobile. Every oil change I add Chevrons Techron fuel injector cleaner also. I have experimented with higher octane but didn’t see a difference in gas mileage so why waste the money?