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I have always been a little nervous about what type of gas I put into my car, I mean I have put all that time and money into it, I would hate to ruin it with some lame fuel. I'm curious as to what you folks prefer? Does it really matter? I am using Shell's V-Power at the moment. What do you trust to put in your baby?

Thanks. :patriot
 

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I always put 92 minimum or highest available in all my vehicles.

Newer engine technologies will detect fuel octane based on engine perf and adjust accordingly. There is a lot of stuff out there that performance differences are a myth, but nowadays there is engine technology that WILL adjust performance based on fuel (or the effects which it can detect, such as knock).

I also had a friend that worked for an oil company, and he said that the higher octane fuels (I think his company supplied Amoco at the time) do have some detergent and anti-corrosion additives that the 87octane fuels didn't, and also usually contain a bit of ethanol, which helps for water absorbtion and anti-freezing.

Being the geek I am, I ran a reasonably controlled experiment with 1000 miles in a cavalier. 1000 miles at 87 octane, 1000 miles with 94 octane shell. The result? about 36 1/4 gallons used for the 94 octane, vs. almost 38 1/2 gallons for the 87 octane. Driving style (me!) and basic route was as identical as practical.

Is that much? prolly not. But the interesting thing is that the cash amount was nearly identical, with the 87 octane at about $1.85 a gallon and the 94 octane at $2.02. Funny, eh?

Supposedly, according to an acquaintance at Powertrain, the Cavalier powertrain is not as advanced as today's ecotec, and there shouldn't have been a difference UNLESS the 87 octane was creating knock.

So, if there is a performance difference (which newer motors do seem to have the capability of making), and there are some added detergents and stuff so I don't have to put STP gas treatment in, it is just easier and makes me feel better to put in the hi-octane stuff.

JMHO, myth-busters out there, fire away. But be prepared to back up your retorts with DATA! :lol

BTW, all it takes is one bad sulfur-contaminated tank of gas to fu*k up your fuel gage, which can make you run out of gas a couple of times, or run your fuel tank low, which uncovers the fuel pump which relies on the gas to keep it cool, which wears out in the most inconvenient place and time, and you get to WALK 5 fu*king miles to a phone in the middle of a snowstorm, 'cause you're in the middle of nowhere where your Nextel phone can't pickup a signal... :mad
 

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I generally go with 87 Octane, and a brand name station (Mobil, Sunoco, etc). My vehicles run fine on the 87 so I have stuck with it. On a recommendation by my POntiac dealer, I did switch to 93 in my Fiero for a time. Probably a few months. But I didn't notice any difference with mileage or performance, and switched back.
 

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Well my feeling is definitely different. On cars spec'd to run 87 min., I don't believe from limited experience that the base timing and fuel maps are aggressive enough to take advantage of higher octane. I do understand that under certain conditions (under load, high temps) the ECU will retard the timing because of knock, which higher octane would have prevented, but I'm not sure I believe the typical vehicle is programmed to advance the timing due to higher octane. That would require the ECU to advance timing almost infinitely until knock was detected then retard over and over. I can't see an OEM programming to live on that edge an still offer warranty. As far as getting better mileage from your test, well calculating sample size for testing in DOE's is what I do for a living so I won't comment on it's validity. LOL It is possible, but unless something has changed, higher octane fuel in and of itself doesn't contain higher energy potential (BTU's) so I can't see it being more efficient. In fact the higher octane is more resistant to detonation so could potentially leave more unburned fuel. Having said all that I admit to owning a vehicle spec'd at 87 that definitely responded to an increase to 89. :thumbs
 

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Actually that's what my Ford ZX2 S/R does. But it takes 2-3 tanks of 91+ octane for it to revert from having 87 octane because it does it very slowly to prevent excesive knocking. The difference is amasing too for my car. However the S/R package option for my car added an upgraded PCM to the car to handle 91+ octane. So since my car uses 91+ octane I put 93 octane in (it's what we get here in FL). In general I use what the car is reated for.
 

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I do a lot of work for Chevron, and they tell me that the only differences between name brand gas and generic gas is in the additives. Generic stations actually purchase surplus gas from major refineries with out the propritery additives, so the quality of refining is about the same. However a generic brand is free to add whatever they like and many of them cut the fuel with ethenol which if used in too high of a quantity can cause deposits.

I personaly stick to major brands and use what ever octane is suggested by the manufacturer. My choice of brands is based more on conveinience and price. Sometimes I will run a tank of Chevron for the additives that help clean deposits, but it is way too expensive to use all the time.
 

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Is the Chevron really that much more expensive in your area then other gas? Because that's what I use all the time and it costs the exact same as all the other places in the area. Even for 93 octane.
 

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My 3.0 Vulcan in my Ranger pings like a Caribbean Kettle Drum band on 87, pings a little on 89, and runs good on 91, which hacks me off since it's supposed to run on 87 no problem.
 

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brentil said:
Is the Chevron really that much more expensive in your area then other gas? Because that's what I use all the time and it costs the exact same as all the other places in the area. Even for 93 octane.
Yeah, it's way more. Chevron does what they call "value pricing", meaning that they price thier gas in each market by what they think they can get for it. I live in the San Francisco bay area, and there are a lot of really rich people here, and Chevron likes to think of themselves as an upscale gas company, so they way charge more. Thier stations are generaly nicer, but I can't afford their gas.
 

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BTW, a half-assed attempt at repeating the experiment above a year or two ago in my old L-van, I got a similar change. Just kept track of tank mileage through about 6 or 7 tanks - a lot less formal, and a lot more highway miles (only use my van for hauling things reasonable distances). About 16.6 MPG with 87 octane, about 17.4 with 94 octane (Shell).

Not that I have an explanation, mind you. I jus' goes wit da data.

I've also heard there is a big difference after a tank or two changeover in the Saturn VUE, not in power, but in peak torque, for the Honda engine. That's from a semi-"inside" source.
 

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AeroDave said:
Yeah, it's way more. Chevron does what they call "value pricing", meaning that they price thier gas in each market by what they think they can get for it. I live in the San Francisco bay area, and there are a lot of really rich people here, and Chevron likes to think of themselves as an upscale gas company, so they way charge more. Thier stations are generaly nicer, but I can't afford their gas.
Wow, that really sucks. :(
With the 8¢ gas tax cut here in FL, plus rates have been slowly going down (hopefully the hurrican coming through my back yard wont make them go up) I'm paying $1.88 per gallon for 93 octane Chevron.
 

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Since most of my retirement's tied up in Phillips 66 stock (and we refine most of the gas in Northern California), I'm glad somebody's buying it. Actually, I work for at a place that's refered to as Chevron/Phillips so I'm hedging on both sides.

I use premium in a Honda that was spec'd for regular, but there's a reason. I found, on this particular car, I could fool the computer by physically advancing the timing (twisting the distributer) and get a measurable increase in HP. Think poorman's computer chip. It moves the center of the computers ignition timing parameters up.

In my car, MPG is about the same with either. I filed two marks on the distributer and, if I'm going on a long (1500 miles plus) trip, I retard it back to factory setpoint and use regular 'cuz in Podunk and Gilla Bend I've seen them ask an extra thirty cents for premium. But I'll pour a can of cheap (mostly alcohol and Varsol) additive in every third or forth tank 'cause ya takes yer chances on the open road.
 

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solsticeman said:
I always put 92 minimum or highest available in all my vehicles.

Newer engine technologies will detect fuel octane based on engine perf and adjust accordingly. There is a lot of stuff out there that performance differences are a myth, but nowadays there is engine technology that WILL adjust performance based on fuel (or the effects which it can detect, such as knock).

I also had a friend that worked for an oil company, and he said that the higher octane fuels (I think his company supplied Amoco at the time) do have some detergent and anti-corrosion additives that the 87octane fuels didn't, and also usually contain a bit of ethanol, which helps for water absorbtion and anti-freezing.

Being the geek I am, I ran a reasonably controlled experiment with 1000 miles in a cavalier. 1000 miles at 87 octane, 1000 miles with 94 octane shell. The result? about 36 1/4 gallons used for the 94 octane, vs. almost 38 1/2 gallons for the 87 octane. Driving style (me!) and basic route was as identical as practical.

Is that much? prolly not. But the interesting thing is that the cash amount was nearly identical, with the 87 octane at about $1.85 a gallon and the 94 octane at $2.02. Funny, eh?

Supposedly, according to an acquaintance at Powertrain, the Cavalier powertrain is not as advanced as today's ecotec, and there shouldn't have been a difference UNLESS the 87 octane was creating knock.

So, if there is a performance difference (which newer motors do seem to have the capability of making), and there are some added detergents and stuff so I don't have to put STP gas treatment in, it is just easier and makes me feel better to put in the hi-octane stuff.

JMHO, myth-busters out there, fire away. But be prepared to back up your retorts with DATA! :lol

BTW, all it takes is one bad sulfur-contaminated tank of gas to fu*k up your fuel gage, which can make you run out of gas a couple of times, or run your fuel tank low, which uncovers the fuel pump which relies on the gas to keep it cool, which wears out in the most inconvenient place and time, and you get to WALK 5 fu*king miles to a phone in the middle of a snowstorm, 'cause you're in the middle of nowhere where your Nextel phone can't pickup a signal... :mad
Fire away indeed! :lol I contacted the big three gas producers (for a job related issue) to inquire if there was any more detergents in the higher priced gas than with reg. gas and was told NO They use the same % in all their grades. The addition of ethanol to pump gas is illegal in Va. unless that information is displayed on the pump. I believe other states require the same disclosure as well.
 

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brentil said:
Wow, that really sucks. :(
With the 8¢ gas tax cut here in FL, plus rates have been slowly going down (hopefully the hurrican coming through my back yard wont make them go up) I'm paying $1.88 per gallon for 93 octane Chevron.
You're paying way less for premium then I am for regular. I think 87 is about $2.15 at the Union 76 last time. I'm a pilot, and not long ago the price for 91 car gas in my area was higher than 100LL Av gas for a little while! It's come down and Av gas went up, but that was a unique moment in time. It's not cheap to live here for sure.

Best of luck and hope all is safe and sound with that hurricane out there. Don't know why they didn't call those storms Bonnie and Clyde. The only good hurricanes are either airplanes or motorcycles, the wind kind sucks ass!
 

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Here in SO Cal, th high grade is 91 and the middle grade is 89... I always put on or the other in my S-10.... no problems for 15 years. Don't know if the gas helps or not, but I am not about to switch to find out.
 

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AeroDave said:
However a generic brand is free to add whatever they like
This is exactly why I stick with major brands. Not necessarily because they add ethanol, but we always have one station or another adding water to the gas around here, and it really shows up once the temperatures start freezing! :crazy The story will break on the news, but people will still buy for them. Their choice I guess, but its not like they are any cheaper. Only Mobil seems to be priced higher than everyone else around here, and even they are usually no more than .03 higher.
 

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Here I like to go to a reputable gas station that does a high volume in sales. I find the more gas they go through and the less it sits around in there tanks the better the gas.The price is always pretty close in price.
 

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Here in OKC, the only brand that carries the 93 octane is Sinclare (spelling?), the price is not high either, do you guys have any opinion on this brand of gas?
 

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gmmerc5 said:
Here in OKC, the only brand that carries the 93 octane is Sinclare (spelling?), the price is not high either, do you guys have any opinion on this brand of gas?
I never heard of them. There are no Sinclare's around this area. They might be ok. Are they a big chain down there? Do they have clean places, modern pumps, etc? I'd ask around with people you know and see if they would recommend them, or warn against them for whatever reason. Word on bad gas and/or stations usually gets around.
 

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Fformula88 said:
I never heard of them. There are no Sinclare's around this area. They might be ok. Are they a big chain down there? Do they have clean places, modern pumps, etc? I'd ask around with people you know and see if they would recommend them, or warn against them for whatever reason. Word on bad gas and/or stations usually gets around.
I wouldn't call them big chain, I personally only know 3 stations in OKC, from the way the stations looks from the outside, they are individually owned, none of them looks the same, the stations looks fairly clean, I don't know what you mean by modern pumps, they do have pumps that let you charge your purchased on your credit cards, I will check around with the local guys who drive Vettes, I know they searches for the gas stations that carries the highest octane.

By the way, Fformula88, still no news on the Saturn kappa?
 
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