Bert

No, he means less as compared to what you would get with the 2.73 gears on the highway

Reason being that on the highway you want to cruise in the top gear and you want lower RPM for better fuel economy -- the 3.31 rear end effectively gears the whole thing lower so you will be turning higher RPM at highway speed than you would with the 2.73's. In the city it doesn't make much difference because you are not cruising in top gear anyway.

OAC_Sparky

A few points from someone in the industry.

1) Ford's "advertised" rating means different things depending on the market it's trying to reach. A V6 Mustang advertisement is targeted more to people that wouldn't normally buy a Mustang in the first place because the preconception is that it isn't very good on gas. So the advertising that the V6 makes "305HP and 30MPG on 87 gas" has value because it makes people believe that they can get their cake and eat it too. The example is the advertising with the Ecoboost engines. When Nissan and Lexus and Ford advertises close to the same power numbers in their SUVs Ford can point out that they make their numbers on regular gas, as opposed to the other two that needs premium to make their numbers. So the gist is that buying the Ford will save you 30 cents a gallon.

So to summarize:
V6 Mustang market target = economy with some power, good mileage
GT Mustang market target = max HP numbers

2) Gas rating does have more of an effect on mileage now; but not from an octane perspective but an ethanol perspective. Most gasoline now is cut with ethanol, to keep the greenies happy. Unfortunately, ethanol when burned in a relatively low-compression internal combustion engine actually produces LESS power (as opposed to alcohol-burning race engines designed for it). While it may reduce greenhouse gasses some when you compare it per gallon of gas used, it also produces less power per gallon used! An analogy: you want to get stinking drunk. What do you drink? Well you can drink a case of beer, or a bottle of JD. If you look at it, that's a lot more beer to drink to get the same amount drunk. When the oil company cuts the gas with ethanol, it's a win-win-win for them. They look like they're saving the planet, they sell more gas (with no drop in price even though ethanol is cheaper) and they pass on more tax money to keep the government happy. But the consumer gets screwed because they get stuck with the lesser gas mileage.

When you look at many gas pumps today, the sticker will usually say that "this gas may contain up to 10% ethanol". The truth is that regular WILL contain 10%, but premium will contain at most 5% because you can't reach 91 or 93 octane with higher than 5% ethanol in the fuel. It would be like saying you can take 180 proof rum, replace it with 10% water and say that it's still 170 proof rum. It just doesn't work.

So you WILL get better mileage on premium. It may take a tank or two for the computer to adjust the curve but it will. When I traveled the border often, before the US started putting ethanol in their gas but Canada did, I could get an extra 50kms per tank using US gas. That's a 10% improvement!

3) All Ford cars have adaptive spark technology and have for quite some time. What they don't all have is variable cam timing.

Bert

interesting point about the ethanol -- however I have checked my mileage on Massachusetts pump gas (which always has the ethanol sticker since the greenies are in charge here) 93 versus 87, and I get the same mileage with the 87 or perhaps a hair better than with the 93

WhiteBird00

I was with you for most of that but there are a couple of misconceptions:

All grades of fuel will have about the same percentage of ethanol. Ethanol raises octane so it's easier to reach 91 or 93 with an ethanol mixture than it is with pure gasoline. The reason the signs say "up to 10%" is strictly for legal and regulatory reasons. For a variety of reasons, it is not always possible (or at least practical) to maintain an exact 10% ratio. Part of this has to do with expansion rates - the percent by volume varies based on the temperature. Also a measure known as relative vapor pressure takes into account the different evaporation rates. So the mix is designed not to exceed 10% ethanol and is usually less than that.

Yes, you will get better mileage on pure gasoline than on E10 but it has nothing to do with octane rating. As I mentioned, all grades get about the same amount of ethanol. Ethanol has about 34% less potential energy than gasoline. So, all other things being equal, using E10 will reduce gas mileage by about 3.4% compared to using gasoline. That percentage can be significantly higher for a variety of reasons including engine computer calibration, driving style, etc. For example, when we were first switching and real gas was still available at some locations, I would notice an immediate increase in performance when using real gas. That allowed me to be more conservative with the "go" pedal so my mileage probably increased proportionally.

I'm not at all surprised that you could see a 10% change in mileage between gasohol and gasoline but it has nothing to do with octane.

JScottGT

There are some stations that sell non-ethanol blend fuel. it may depend on what state you are in though. I know that in MI, typically BP fuel is not blended, and I do typically see an increase (1-2 MPG) in everyday driving mileage using BP fuel in my car. Maybe this is why the Ford placed the label on the fuel caps of most of their cars recommending BP fuel.

OAC_Sparky

What I said*:
*But you were correct about octane rating (ie resistance to preignition) in ethanol is higher.

It may be different in your state, in Canada the concentration of ethanol decreases in the higher grades. Between the higher octane and lower ethanol is why you see the marked difference in mileage. Now, is it enough to justify an extra $.60-.80 a gallon? Hard to say, when gas is already over $4 a gallon here (ie $4.10USD/gal vs $4.75USD/gal)

WhiteBird00

I don't know where you heard that. I work for a Shell jobber and I just checked with our Shell rep. There is no difference in ethanol blend percentage between the various grades - if regular is getting 8% ethanol then premium is also getting 8% ethanol. The same applies to both the US and Canada. The only difference (other than metric versus standard measure) is that Canadian dispensers (pumps) must be temperature compensated whereas US dispensers generally aren't.

OAC_Sparky

I usually don't buy Shell, but PetroCanada (one of the biggest chains here) advertises it as such.

rodmoe

So why are they temperature compensated in the Great White and not for a few hundred miles south near the frozen tundra ? Or in plain engrish why Canada and not the northern US. What does that compenstation do ?

OAC_Sparky

Temperatures in Canada have a greater range than most of the US, for example in Toronto can go from 105 degrees F in Canada in the summer to -25 F in the winter (not even factoring in wind). The change in temperature causes a change in volume so the pumps would never be accurate if they didn't change the calibration to compensate.

WhiteBird00

That is true but the reason is somewhat more basic - Canadians have more government regulation than Americans. Consumer groups have been pushing Congress to require automatic temperature compensation on dispensers for years but the fuel industry lobby has been powerful enough to block such attempts.

rodmoe

OK Thanks i can see where the wrong reading at the pump would give you wrong MPG readings if you did the math yourself. as for rules and regs i am sure they are coming.
i cant recall the last time we hit 100 deg F but i remember the week of -30's and that was rough i'll take the snow before the cold anytime !! sorry to hijak the thread ...

Itravelalot

Goverment regulation??? I live in the Phoenix, AZ area. Tell me, who benifits more from temperature compensation in Canada? Now how about in Phoenix??? As the temperature gets colder, generally gas should get denser and the oil companies will have to effectively give out more gas if they do not compensate for temperature than they would when they do. The oil companies have no reason to fight a government regulation that works mostly for their benefit. While it is true that Canada does have more temperature variation than the US, the average is still much lower. Since the tanks are a little under the ground, the relatively short periods of high temperature will have much less effect there than they do in Phoenix.

While the ambient air temperature in Phoenix rarely gets over 120 F in Phoenix, it does stay between 100 and 120 long enough that the ground where the tanks are stays very warm for a number of months at a time. When you add the heating effect that asphalt and concrete can have, real temperatures can be much higher There is a good portion of the year here where you just can not get cool water out of your faucet, once the water from the pipes inside the air conditioned part of the house runs out. The gas in the tanks here in Phoenix stays hot at all times day or night through much of the year here, and hot gas is less dense. I can not realy complain though, because it is all worth it for 365 days of good driving weather per year.

In Summary, I really do not think it just a stricter government that makes the difference between the policies of Canada and the US. The Oil companies would make money off of temperature compensation in Canada, and would likely lose money in most of the states in the warmer US.

Bert

here in the Communistwealth of Massachusetts, pure gas is illegal, immoral, fattening, and sure to cause extinction of the human race within the next few days if not sooner

KonaBlue5.0

I realize this thread is way beyond this point, but I just figured I'd fill you in. Remember, this was all based on the '11 GT, not the V6, as I had missed that part of the first post.

The gear spacing for the '11 GT is much, much tighter than on the '05-'10. 1st and 2nd gear are pretty much interchangeable, as from redline in first shifting to second only drops you like 2000 RPM. It's almost a waste to use both gears when not racing. 2nd gear in the '11 GT is only slightly longer then in the '05-'10 GT's, it feels almost the same to take off in 2nd in the '11 as it did in my '08.

The rest of gears follow the same path. 5th gear is our 1:1 gear, whereas 4th is for your 5-speed, so we are covering 5 gears in the same span of ratios as you are with 4 gears. Skipping gears with the '11 GT ends up being like shifting an '05-'10 GT normally.

WhiteBird00

The resistance from the industry has more to do with the cost of upgrading/replacing existing dispensers at all locations rather than the actual benefits/drawbacks of automatic temperature compensated dispensers.

But you're right - they do gain from the lack of temperature compensation at the retail level. This is primarily because fuel sales at the wholesale level are temperature compensated. Fuel at wholesale is compensated at a seasonally variable level but usually around 65 degrees F. So, in the south where temperatures are usually higher, the station can sell more volume than it buys (a pretty neat trick if you think about it).

OAC_Sparky

It's only neat when you're the seller not the buyer.

eric n

I might be wrong, OFTEN AM, but it would seem since they make no mention of requiring premium and in fact state that it takes 87 octane, the 412 would have to be at that octane rating.

Further dyno evidence seems to indicate that 87 octane produces number that would indicate right at 412 engine HP and that 91/93 seem to be producing more like 430 at the crank. Again I could be wrong and even if I'm not I'm sure someone will say that I am.

Fire512

The same in Fla. 10% ethanol by state law.

WhiteBird00

The 2011 brochure (page 13) has a little note 1 after the 412 hp @ 6500 RPM. The note at the bottom of the page reads "Figures achieved using premium unleaded fuel". There's no mention of whether that's 91 or 93 octane. I read somewhere else that it's rated 402 at 6500 using 87 octane regular gas.