To premium or not to premium.........?????

[NightRiderQ45]

I've ran both in my car and I've actually gotten better mileage with 87 due to the fact that octane is "moving" out of the station quicker than the "cut with unleaded premium 91" here. When I was back home, I always ran 93 octane and got the best mileage out of my car. My car even runs differently when I travel back home. But this garbage 91 premium here is horrible. I filled up on 91 Shell V-Power yesterday morning to try out the nitrogen junk and I'm sitting on half tank today after I pulled into the plant !

[TellarHK]

You're talking about using 93 octane in a car for which 91 octane is recommended. You'll probably get as much out of 93 octane in the Q, as a Chevy Malibu would get out of 91 octane. If you're paying $.33 extra for 93 octane when you could be paying $.20 extra for 91, that's your choice but the car shouldn't notice.

At my altitude (4500 feet above sea level) I can tell a distinct difference in the power of my Q whether I feed it premium or regular.

[maxnix]

First, one has to realize that these engines were designed around a certain combustion process involving certain fuel and ignition device.

Second, the culmination of that design is specified in both the FSM and OM.

Any variance is at the consumer's own risk!

Does anyone think anything like the test fuel quality of the late 1980's is avaiable today from a retail pump?


Modified by maxnix at 4:05 PM 6/25/2009

[NightRiderQ45]

What are you talking about Tellar!? Back in Alabama they sell 87 89 93 octane gas with .10cent difference between octane. Here in OK they sell 87 89 91 with .10 cent difference with no choice of 93! Where are you getting you numbers from!? I'm not speaking of "probably" I'm speaking of actual facts. I could clearly see my mileage drop after moving here to OK using 91 after I've spent ALL of my life using 93 gas. My gas of choice when I go home is BP and Cheveron and since I've been here in OK, I've never seen either of the two stations here. Both have given my car over 300miles to fill up but I haven't seen that mileage since moving here.

[GThreat]

I think one of the problems with the argument stated was the oil execs have pulled off a big rip off. I am not sure who actually listens to them when it is time to add fuel to the engine. I side with the engine designers here and I doubt they are getting kick backs from the oil companies.

[maxnix]

The only thing you will "break even"ly is your engine which is designed for 91 octane Tier 1 Premium.

In this context, ethanol is a contaminant. Heath's experiment with after market made in USA injectors has gone well for 3 months.

[TellarHK]

What are you talking about Tellar!? Back in Alabama they sell 87 89 93 octane gas with .10cent difference between octane. Here in OK they sell 87 89 91 with .10 cent difference with no choice of 93! Where are you getting you numbers from!? I'm not speaking of "probably" I'm speaking of actual facts. I could clearly see my mileage drop after moving here to OK using 91 after I've spent ALL of my life using 93 gas. My gas of choice when I go home is BP and Cheveron and since I've been here in OK, I've never seen either of the two stations here. Both have given my car over 300miles to fill up but I haven't seen that mileage since moving here.

I'm talking about Carson City, Nevada - Bangor, Maine - Manchester, New Hampshire, and pretty much everyplace I've ever lived in between (Houston, Texas - Peoria, IL - Modesto, CA) where gas typically comes in 87-89-91 octane options. 93 octane is a fairly rare sort, and primarily only common in your oil states - Texas and Oklahoma, where the distance to the refineries is shorter. I've seen 93, but it's far from the common "Premium" blend.

And a $.10 difference from one octane to another is what I'm saying. Base price is for 87, then another $.10 up to 89, and another $.10 up to 91 = $.20 extra, per gallon.

Now I'm not saying anything about getting better mileage, I'm talking about power. Actual horses on the pavement. I do almost all my driving at high altitude, and a significant number of trips across the mountains into California that take me across I80 or highway 50 at 7-8000 feet. On those drives in particular, the Q feels a lot more responsive when I'm giving it 91 octane as opposed to 87.

[TellarHK]

I'm one of the folks around here that typically complains about people who say "OEM only, FSM specifications or just sell your car to someone who cares!" and the like, but I'll go out on a limb here and agree with maxnix.

These cars are designed and built for a very specific market, the high-end luxury performance sedan. As such, these engines are designed with very clear tolerances and preferences, as are most "Premium Fuel Only" models of car. In the case of the Q45, you're far, far better off playing it safe and sucking up the extra $4 per fillup than you are risking an engine problem that may or may not happen ten, twenty, or even thirty thousand miles down the line simply because it's going to be damn expensive and in one big lump sum.

As far as your mileage of 275 goes, that's incredibly low. You have a 22 gallon tank in that car, and at that rate you're not even pulling a solid 15 miles per gallon. If you're that much of a leadfoot, then you can expect to keep getting a sore backside at the gas pump. It's fun to drive these cars a little heavy, but it's expensive compared to something like a Honda Civic that weighs half and has half the horsepower running on regular.

I don't know what my "new" mileage is going to be running premium now that the seeds are out of my intake, and I suspect it wouldn't compare all that well considering my high base altitude. I ran a bit over 300 previously, however, and usually fill up with 3-4 gallons left.

Ethanol, by the way, is best thought of as just an octane booster. If you're running at 93 with 10% octane, it's likely the base fuel is a lower grade and the ethanol is what jacks that up to the equivalent of a proper premium fuel. If I'm wrong about this, I do hope someone will correct me, though.

[macmanks]

Very interesting commentary. Keep in mind these facts:

The octane rating on the fuel each of us purchases by law MUST rate at or above the MINIMUM rating posted at the pump. That means if you are buying 87 octane the octane rating of the gas is at least 87 and likely higher because as a supplier it is a major no-no for your tested fuel to fail to meet the minimum rating.

Also does anyone really think there are four or more larger pipelines running from the refinery to the storage tanks: an 87 line, an 89 line, a 91 line, a 93 line, etc? HA!!! Wrong if you do. The fuel all flows through the same line.

Ethanol/alcohol has a much higher octane rating = more power. More power equals greater acceleration by using the energy but less mileage because the energy was expended on a quick start. Heavy feet yield worse mpg no matter what fuel you use due to the same principle.

Lastly, aside from the mix of additives such a s cleaners or ethanol there is absolutely zero different between the gas you buy at the "cheap" station vs. BP, or Shell, or QT, or Citgo, or Marathon, or Speedway or any other brand for that matter AND the 87 rated fuel will pass the 91 test almost without exception.

Fuel blends during the summer have to produce lower emissions which means it is a cleaner fuel (more diluted with additives) and everyone's mpg will decline during the summer. The hotter the air temp, the more gasoline expands but you will have less energy in your tank compared to a cooler day. Always fill up at the coolest time of day to ensure you get the most gas for your money.

Most of you will refuse to believe these simple truths, but hey - most of us live in denial about any number of things every day...

[NightRiderQ45]

Macmanks....FINALLY someone one here who actually knows about the process of gas! That's why I made the statement earlier stating that "91" is seriously cut with regular unleaded gas. If you can get 93, that's what you need to use. I'm glad that you made the statement because this site is full of people with no petrochemical knowledge but speak like they are masters.

Lastly, aside from the mix of additives such a s cleaners or ethanol there is absolutely zero different between the gas you buy at the "cheap" station vs. BP, or Shell, or QT, or Citgo, or Marathon, or Speedway or any other brand for that matter AND the 87 rated fuel will pass the 91 test almost without exception.The statement about is soooo true!! I listen to people scream "top tier" and I laugh at their statement! That is marketing 101! Tell me why the heck do you think the largest oil company in the world Exxon-Mobil ISN'T on the top tier list??? Are you saying that their gas/products are inferior!? Heck no it isn't! They don't need to PAY to have their brand listed on this "top tier" list because they are already #1! I have friends who have over 30 years of experience with petrochemical (midstream, upstream, terminal) and ALL DIFFERENT BRANDS of gas comes out the SAME PIPELINE!!!!!!!!! There is NO DIFFERENCE! They add "additives" to the base product to make it their own product. Its just like oil, ADDITIVES are added to the base product. These "additives" are a complete joke to tell the truth. I know FOR SURE that they add less than 1 gallon of their "additives" to an 8500 gas tanker before it hits the station! I tried to find out the exact amount but he wouldn't tell me but even if it's 1 gallon, what effect do you think that its doing to a 8500 tanker?? V-Power, Techron...please! If you are counting for techron and v-power gas to keep your injectors clean by the gas itself, you are seriously kidding yourself. Stick with otc products to help with clean injectors.

Macmanks...you don't have to sell the FACTS to me, I already know.

[aces805]

macmanks: What kind of gas do you put in your car?

[Infinitiguy19]

I am still waiting to hear from Q45tech on this one before I make a Judgement.

[TBrack]

wow I get like 440 miles off of a tank with Conoco 93 octane. Then again, all my driving is interstate travel...

[BadQ45t]

Well the CA guys know we have not seen 93 octane in the last 10-15 years.

Lasoyahfan, overall 400 miles on a tank in a 1st gen, I had a 92' for 6 months (my dad's old car) that was in very good working shape and never got close to that. Was that just totally 55mph? If not keep doing whatever you doing, I got it to 375 with the warning light on once or twice...than again I have not seen 93 in a long, long time...nor has AMOCO ever sold gasoline in CA in my lifetime.

[sebvox]

The 76 on Herndon in Fresno, CA used to sell 100 octane. But that's when they were the official gas of NASCAR a few years ago.

[lino]

Well the CA guys know we have not seen 93 octane in the last 10-15 years.

Esso gas stations (Canadian version of Mobil) use to sell 92 but bumped it down to 91.

Most gas stations here sell:

Regular - 87 octaneMid-grade - 89 octanePremium - 91 octane

and there is: Super premium - 94 octane (Some Petro Canada gas stations in Montreal)Ultra 94 - Sunoco in Ontario (up to 10% ethanol)

Gas stations in Canada selling ethanol-blended gasoline have a label on the pump indicating the gasoline may contain up to 10% ethanol.

[TBrack]

Well the CA guys know we have not seen 93 octane in the last 10-15 years.

Lasoyahfan, overall 400 miles on a tank in a 1st gen, I had a 92' for 6 months (my dad's old car) that was in very good working shape and never got close to that. Was that just totally 55mph? If not keep doing whatever you doing, I got it to 375 with the warning light on once or twice...than again I have not seen 93 in a long, long time...nor has AMOCO ever sold gasoline in CA in my lifetime.

I cruise at 80mph almost everywhere. There's a warning light?!?! Mine has never worked I guess. The only thing really different is I have the early model ecu, custom cai, and custom exhaust. The stock mpg is supposed to be like 21 on the highway so 440 from a 22 gal tank is pretty right on.

[Victor]

Some facts1. The higher the altitude, the lower octane rating you need in your car. That's why regular at high altitude gas stations is usually 85 or 86 octane, but go down to a lower altitude and it goes up to 87. The reason is air is less dense at higher altitudes, so the amount of air in the cylinder of a high compression engine at high altitude would be close to the amount of air in a low compression engine at sea level of the same displacement.2. It is possible to put several grades of gasoline, or even diesel, through the same pipeline from what I read. They keep them separated by a balloon of some sort that travels along the inside of the pipeline, going with the flow. There is probably a little bit of mixing, but after they load it into a 500,000 gallon tank a the end of the line the mixing effect is negligible. I'm not sure if the balloon is to actually keep them separated, or whether it just serves as a marker to tell them when its time to switch to a different pipeline of storage tank.

[TellarHK]

That's some interesting information. The "balloon" trick is pretty clever, you could almost say it packetizes the flow.

Not sure I'd agree with "Usually" in regards to high-altitude gas stations being 85-86 octane, unless high-altitude is significantly more than the 4500-5000 that I live at. I can't say I've seen a gas station with grades other than 87-89-91 since I lived in Houston, save for some racetracks. And one specialty station that sold 100 octane in Haverhill, Mass.

It's always seemed to me that you mainly found the 93+ octane levels in areas serviced by nearby refineries or racing facilities, or a few stations in a major metropolitan area catering to a specific market.

Regardless, this business of having winter and summer blends, three to five grades of fuel and different variations per state is just nonsense. We need three grades, a national standard for fuel blends - you can even keep winter and summer blends if you insist - and a cutting of all the red tape and production throttling that screwed New Orleans over during Katrina. Remember all those shortages? That wasn't a lack of refinery capacity, that was a lack of refinery capacity using a blend for Louisiana's state-required mixture.

89, 92, and 100 octane. Should be enough cost savings to bring the price of 89 down below today's 87, and 92 should cover any reasonable non-boutique private vehicle. 100 (or whatever the most common rating is) for racing.

Our wallets, Q's, and supply mechanisms would all be happy.

[Infinitiguy19]

N/A

[NightRiderQ45]

Lasoyafan...how the heck are you gettting those miles!?! I wish I was in your situation because my car gets 275miles from full to 1/4 tank. I don't know how many miles it can get until the warning light comes on...really because I don't never let it get below the 1/4 tank.

Oh Paul Wall, you can wait for Q45tech all you want but he isn't the "all knowing" person on every subject. Yes he knows a lot about our cars, but I think that I'll trust people with over 30yrs experience in the petrochemical field over what tech thinks.

[Infinitiguy19]

Oh Paul Wall, you can wait for Q45tech all you want but he isn't the "all knowing" person on every subject. Yes he knows a lot about our cars, but I think that I'll trust people with over 30yrs experience in the petrochemical field over what tech thinks.

I know that he is no God, But he is one of the most knowledgeable members on this forum. And if you truly did read any of his posts you will see several discussed petrochemicals. No offence.

[NightRiderQ45]

I know that he is no God, But he is one of the most knowledgeable members on this forum. And if you truly did read any of his posts you will see several discussed petrochemicals. No offence.

I take no offense to your statement at all. Yes he knows a lot about our cars but why should I read his posts concerning gas when I have friends who have first hand unbiased knowledge about the subject. If tech has 30yrs in the field then I will listen but until then, I think that I'll believe what my friends say who works in the field everyday. Last I remember after reading tech's posts, he works for a repair shop daily right?

[Infinitiguy19]

Why don't your freinds post on NICO so we can all see what they have to say?

But I am always afraid to believe what I hear on a forum because after all a 13 year old can post what he or she wants.

[NightRiderQ45]

But I am always afraid to believe what I hear on a forum because after all a 13 year old can post what he or she wants.

So what is the point of actually joining the site? If that was the case, then we all are wasting our time posting right? First you say that you are waiting for tech to post so that you can get his approval then you turn around say that you are always afraid to believe what you hear on this forum because any age can post So have you been believing his post to date?

Maybe I'm reading your post wrong but it sounds like you just contradicted yourself. Oh, they are not going to join this site, I was just stating what was told to me. Like macmanks stated earlier...people live in denial everyday...you can choose to believe what you want. Trust me I won't loose any sleep.

[TellarHK]

Do you have any more info on this gas station please?

Absolutely.

Haffner's Service Station Inc‎.73 Plaistow Rd, Haverhill, MA‎(978) 374-2059‎

Google Maps street view: http://maps.google.com/maps?f=...,,0,5

[Infinitiguy19]

So what is the point of actually joining the site? If that was the case, then we all are wasting our time posting right? First you say that you are waiting for tech to post so that you can get his approval then you turn around say that you are always afraid to believe what you hear on this forum because any age can post So have you been believing his post to date?

Maybe I'm reading your post wrong but it sounds like you just contradicted yourself. Oh, they are not going to join this site, I was just stating what was told to me. Like macmanks stated earlier...people live in denial everyday...you can choose to believe what you want. Trust me I won't loose any sleep.

I believe Q45tech because he only speaks the truth, othere wise I doubt that he would post false facts over and over and over and over again.

And my point is that your getting your facts from someone who has never posted here himself so people can validate his facts.

[NightRiderQ45]

I believe Q45tech because he only speaks the truth, othere wise I doubt that he would post false facts over and over and over and over again.

But my point is you can't beleive Nala when he says he found a girlfriend (Nala is the General Chat dumbass) or when Unknown007 says he is going to restore his car to OEM performance standards. I can only trust people that have been here for a long time.

And my point is that your getting your facts from someone who has never posted here himself so people can validate his facts.

LOL @ your two examples...I understand where you are coming from though. Even though what I posted are facts, I can understand where you would be confused if were not in the circle of people with that knowledge.

Let me ask you this though, why do you think that Exxon Mobil isn't on the "top tier" list or better yet do you think that XOM's gas is worse than any of the other brands (especially the no name brands you haven't heard of) that's on the "top tier" list because XOM isn't listed?

[TellarHK]

To be honest, I'd prefer the input of someone who knows firsthand how our cars handle fuel, than any second-hand input regarding fuel branding. The exact chemical composition or additives or whatever relating to fuel, is completely irrelevant until it impacts on the performance of my car.

As far as I'm concerned, my experience tells me that my car, in my location and under the conditions I drive it, likes 91 octane so that's what I feed it. If I can get it without ethanol added, all the better. The extra $4 a tank doesn't really mean anything to me. It's simply the cost of a quality car.

[macmanks]

Aces, that is a humorous question. I put Gasoline in my car. Most often I buy it at Sam's Club because it is right by work. I always fill up at or before 1/2 tank so as to keep the fuel pump submerged. I stay away from older stations because I have no way of knowing how old the tanks are and I don't want the crud in my fuel system. I also NEVER buy fuel when a station is getting a drop (delivery) or shortly thereafter because the refill of the tank kicks up the crud. I always fill up at the coolest part of the day when the outside temp is above 55 F.