Ive been reading up things and learned that the btus of the gas of old is 25 percent higher which would mean we would be getting 50 plus in our cars. I also read that high octane can be burned in a low compression engine as long as there is turbulence which our cars have, and that the highest compression was 8 to 1 80 years ago. Ethanol raises the Volumetric efficiency and has a lower flame temp. Denotation is cause by 2 things 1 the end gas burn before the flame front gets there and 2 the fuel burns too fast and uncontrolled combustion happens. Here is a good summary.

Quote from The-High-Speed-Internal-Combustion-Engine-by-Sir-Harry-Ricardo
Liquid fuels carried out on behalf ofthe Asiatic Petroleum Co. may be summarized as follows :— (1) It has been proved that the tendency of a fuel to detonate is the one outstanding factor in determining its value for use in a constant-volumeinternal-combustionengine.Compared with this, most other considerations are of secondary importance. (2) There appears to be little doubt as to the correctness of the view, now generally accepted, that detonation is largely dependent upon the normal rate of burning of the fuel and is less the lower the rate of burning. (3)In all cases it seems that a low rate of burning is advantageous. No fuel has yet been found whose rate of burning was too low to permit of maximum efficiency being obtained in the highest speed engine yet tested. (4) Fuels capable of standing a very high compression will operate in a low compression engine, equally as efficiently as those whose normal rate of burning is high—provided that there is a reasonable degree of turbulence in the combustion chamber. (5) Apart from the limitations introduced by detonation, the power output obtainable from all volatile liquid fuels, with the exception of the alcohol group, is the same at the same compression to within less than 2 per cent.Such variations as occur, within this range, are due rather to variations in the latent heat of evaporation than to any other circumstance. (6)Owing to the high latent heat and low boiling point of alcohol and certain other bodies, the weight of charge per cycle is greater and a higher power output is obtained in consequence. (7)The efficiency with which all volatile fuels, other than alcohol, &c., are burnt is practically the same, atthesamecompressionratio, irrespective of rate of burning, provided the compression is low enough toavoid detonation under any circumstances.In the case of alcohol, the efficiency is slightly higher, on account of the lower flame temperatures.(8) The useful range of burning is, to all intents and purposes, the same for all volatile liquid fuels, (9) The unavoidable losses due to the combined influence of dissociation and change of specific heat at high temperatures are substantially the same in all cases. (10) All the experimental results indicatethat the performance of any combination of hydrocarbons as regards detonation, and therefore the power output and efficiency obtainable, is the mean performance of each of the components.The performance of any complex fuel such as petrol can therefore be predicted,once the nature and proportion of its constituents are determined, or conversely, a fuel can be prepared to give any required performance, within the limits available. (11) The highest useful compression ratio for, and therefore the power output obtainable from, any petrol is governed by the relative proportions of aromatics, naphthenes, and paraffins it contains—the smaller the proportion of the latter the better from almost every point of view. (12) To judge of the quality of a fuel by its specific gravity is entirely misleading.If naphthene and aromatic fractions are present in any large proportion (as is frequently the case), then a high specific gravity is a substantial advantage.

 

30.6 mpg, same station, same route and the weather has been about the same,although it was a little over 60 yesterday. My OBC started out on this tank at 38.9 mpg, but I never take that as gospel anyways and then it just went down and down. Is there any chance the stations are switching back to spring/summer blends and the OBC is making corrections

I thought I was turning the corner a couple tanks back with that 36.0 mpg but since that I've been down to 31.5 and 30.6 mpg. I did have about a half a tank this morning when I filled up and had a full tank of 93, so I put in 89, couldn't pay that $4.09 price, although its only .20 cents more than the 89, I guess I couldn't bring myself to do it....yet! Next tank I will "bite the bullet" so to speak and top off with 93

Any thoughts on this guys?

 

Not sure what's up... I just did a switch to Ultra93 and am also seeing a slight drop in MPG.
Not sure on the blend change - I do know I live in a RFG area but can find no info on the winter/summer info.

My pessimism tells me it's all part of oil's smoke and mirror campaign - but that's only me_

 

I can see by your use of the term "smoke and mirrors" that you are a conspiracy theorist.... You wear many hats, don't you?

 

What's the conspiracy on this one, worse gas products to spend more money

 

I think to an extent it is healthy to have your skeptic's hat on, and in some sense we all subscribe to some sort of conspiracy theory or suspicions at some level.

As long as none of K_C's hats are made of tin foil I think he'll be just fine

 

Tin hats for the Tin Man _

 

Hell, I have at least 2 dozen hats and all of the ones I frequently wear are lined with a couple of layers of foil unless I am driving to the big city when I add another layer... It's hard to have lived 61 years with an open mind and not be aware that things aren't as they appear to be...AboveTopSecret.com - Real-Time Headlines, Picks, and Replies

 

Crank it up brother - JOE CROCKER

 

I am with you on the confusion, gas prices should be 2.50 because of winter gas. I have a feeling you did not fill your tank up all the way and the station also could be cheating you too. Stick with 89 and wait till mpg drops and then try 93. I will continue to use 93 because of the high speeds I drive on the highway. 93 was 3.89 here. I think they start the move to summer gas in a few weeks. March 15 and probably that a week before they get fuel so closer to April. May 15 I believe they start using summer gas. You will start to see driveability problems soon until the summer gas come into play. http://ethanolrfa.3cdn.net/dd9e74ce1..._rbm6bdgh3.pdf is good article but confuses people on engine knock.

 

I go to the same station and usually the same pump even but the boss could be messing around. The OBC today was down to 29.7 mpg but made it up to 30.7 mpg when I pulled into the driveway, I just don't get it

I just want it to warm up so I can get the very most out of this expensive ass gas we're paying for right now! $104 a barrel and its already $4.00 a gallon, 4 years ago it was $148 a barrel and I remember paying $4.25 a gallon for my 07' Mini Cooper S but that was back home in the D. Can't we just bomb the entire region, put a large straw in the ground and suck all the oil out

 

We can only do the best we can - I spent 16K to get 15MPG more than I was getting from my 14yr old Cadillac just for this reason.

Thing is there's plenty of oil out their. Issues involve getting it in this environmentally conscious time.

USGS Release: 3 to 4.3 Billion Barrels of Technically Recoverable Oil Assessed in North Dakota and Montana’s Bakken Formation—25 Times More Than 1995 Estimate

 

I dont get why price are high, the winter fuel is cheaper to make and we are getting burned. The prices went up in summer because mpg is up and there profits fell, so they raised prices to keep there profits. If the demand fell prices still would go up. Taxes would increase to keep prices where they are or higher. Its a catch 22 and no right answer.

Ive been see a lot of commercials for ethanol stabil Deprecated Browser Error if you look at the ethanol it stops corrosion, and absorbs water. I though ethanol was safe. I also reading that they are having problems passing E15-20 mixes because of engine failure.

 

I've been using Sta-Bil in the lawnmowers for years. They sit out a season in a cold garage. As far as their 'ethanol' claims... I'm not sure if a hit of dry-gas wouldn't do the same thing.

Keep in mind the phrase 'Snake Oil in a Can". Not to say it is, but... well, possibly it's just a marketing ploy for their 'new' product.

 

I am just pointing it out, That goes to the bad gas thread I started and every one said theres nothing wrong with ethanol.

Thats another reason I like premium, never had issues.

 

The pressure is on to increase the ethanol mix. Everyone is trying to capitalize on the trend. Think corn. The most expensive way to get ethanol, also the most subsidized crop our leaders are vested in.

New cars are safe w/ ethanol - to a point. The older models have issues with rubber seals, tubing and the such dissolving. I my mind it all boils down to corn.

 

Investors speculating that prices will rise because of problems in the middle east is what is driving the prices up... They are pumping big time in Oklahoma but have to haul the oil by truck to Louisiana to get it refined.. Lots of the old oil pipelines have been dug up because of deterioration and not replaced due to oil being imported in rather than being pumped here from existing wells.

 

To a point 10 percent has been here since the 70s and they had problems since. Heres what I found http://www.crcao.org/news/Mid%20Leve...Sep23_2010.pdf

I understand its 20 percent but Minnesota is trying to get this passed and not that much different to E15.

 

Saudi said they would keep the oil flow the same so no shortages. I understand that they also want to make more money so maybe after a while it will stabilize, but I doubt it. We have enough oil and the summer gas is just starting to hit the market. The refiners should have shut down for the switch to alyklates and reformed gas.

 

Here is more info about what the API has to say about octane. Gasoline -- Is It All The Same? What about Octane? Look how they havnt updated. MTBE has been phased out since 2007 and carburetors havnt been used in cars for 20-30 years.