Cornezy

so far I've been driving my YB sexy beast like I stole it but I have noticed that it seems that my sexy beast has a bit of a drinking problem! Is it me or why does it not seem like the fuel economy is correct? So my question is what shifts are you guys using to preserve gas? (for ones that may have tried) what RPM level are you shifting at? I use premium too....my Blaze is a a V6 6sp with PP Also, does the PP 3.31 ratio burn more gas? just seems like I fill her up way too often...........i know i know........thats what she said! lol

Ltngdrvr

You haven't said exactly what the fuel economy has been, miles driven against gallons used, not what the dash readout shows.

Any car that you drive the wheels off of is going to use lots more gas than one you drive nice.

And the 3.31's will make it get less fuel economy on the highway than the 2.73's but won't make much diffeence in town.

And as far as shift rpm, to get the best fuel economy you need to shift up as soon as you can and use the highest gear possible for the speed you are running. The car will lug itself around at 1200 rpm at cruise so I would target that RPM when you are just running easy.

Bert

For comfortable every-day economical driving I use light throttle and find myself shifting right around 2000-2200 RPM. This gives acceleration that pretty well matches the typical flow of traffic and feels "comfortable" meaning that it is not bogging the engine.

In my 2010 GT, driving this way, around town stop & go I get low 20's (about 22) and on my 1/2-highway, 1/2 backroads cruise commute I get about 27+ MPG.

At a cruise it feels comfortable down to about 1500-1200 RPM, toward the lower end of that range it feels like it is going to bog if I try to accelerate. (easily cured with a downshift)

For the V6 you might need to shift a little higher in the RPM's . . . but you should get better mileage than I do.

Of course that is after break in and after you get tired of driving it like you stole it!

EDIT: Nope, you will never "get tired of driving it like you stole it" but maybe you can resist a little after the newness wears off!

JScottGT

Another trick you can try when driving easy, is to skip gears. Go 1-3-5-6 The gear spacing in the first 5 gears is pretty tight and with the 3.31:1 gears it should be able to do this pretty easily shifting at about 2500.

KonaBlue5.0

I find that first and second gear are basically interchangeable. 1-3-5-6 is nice, but for anything that is angled even slightly downhill, I prefer 2-4-6.

Even staying with low revs, this allows you to get up to around 20-30 mph before shifting, which is especially nice for things like making turns from a stop light that involves going across an intersection. If you are going 1-3-5-6, you end up going 1-3 in the middle of the intersection, left with low revs and possibly bogging to accelerate once you are going straight.


Edit: One thing you need to remember when skipping gears is to be kind to the syncros. For instance, going from redline in first gear directly into 4th without letting the revs drop is horrible for the syncros.

Ltngdrvr

You guys giving advice about skip shifting and taking off in 2nd need to realize that the OP has a V6 car and the drop between 1st and 2nd is greater than in a GT.

WhiteBird00

And nobody noticed that he has a V6 and is using premium gas for no good reason? That's 20 to 30 cents per gallon being wasted! Premium gas isn't better gas - it just resists knocking more. In fact, running premium in a car that only needs regular can cause worse gas mileage because of the fuel's resistance to ignition.

JScottGT

Good point, I didn't even notice that. There is no reason to be running anything more than 87 octane in a V6 car. There is no adaptive spark advance/retard like there is in the 5.0. It is just a waste of $0.20/gal. I'd say to try out a couple tanks of 87 and see if there is an improvement just from that.

Ltngdrvr

The 2011 V6 cars do too have adaptive ignition timing just like the 5.0 cars so premium gas will give a few more HP just like it does on the 5.0 cars.

Either car will run on 87, and either car will make more power when running 91 or 93.

Bert

Regardless of the gear ratio spacing, I just don't get this bit about skipping gears . . . yes I do understand what they are saying, but I don't understand why you would want to do it . . . you want the engine running in the best RPM band as much as possible; for my car this means about 1700-2200 RPM for normal everyday cruising, and if I shift 1-2-3-4-5 I can stay in that range . . . if I skip gears, I either have to rev it too high before I shift, or bog it way down after the shift. If I wanted to avoid the effort of moving the stick shift I would buy an automatic.

I'm not so sure about that, there have been some other threads on here about the new V6 making more power on 93 than 87 octane, not sure if it is correct. However for gas mileage the lower octane is generally better.

WhiteBird00

Yes, the V6 has adaptive ignition timing... just like almost every FI car made in the past 10+ years. It's nothing special, my 10 year old Trans Am has it. All it means is that the computer will adjust the spark advance to avoid knocking based on the quality of fuel whether because of octane rating, ethanol content, or whatever. In general (and up to a limit), the more you advance the timing, the more power you can produce. Conversely, the more you retard the timing, the less chance of engine knock and also the less power produced.

The 5.0 is rated 412 HP running on 93 octane. It will run on lower octane fuel but the timing will be retarded and less power will be produced. That doesn't mean that more power will be produced with higher octane. The timing with 93 octane may already be as far advanced as practical. Of course it's possible that Ford chose to rate at 93 octane because it's the highest octane commonly available so it's also possible that there might still be room for more spark advance and higher octane could produce more power... I don't know.

However, the V6 is rated 305 HP running on 87 octane. Ford has made a big deal about advertising this. This would appear to be the upper limit of it's power production. If higher octane and more spark advance would produce more power, it would have been advertised that way (Ford would love to say they have a 315 HP V6). After all, the ads don't say what kind of fuel - you don't find that out until you read the owner's manual.

I think it's safe to say that running 87 octane in a V6 gets as much out of the engine as you're going to get and that higher octane is just a waste of money.

Ltngdrvr

Believe what you want but you're wrong, the V6 is rated as it is because it is touted as the fuel economy leader and budget performer so it is rated with the cheaper fuel.

WhiteBird00

Do you have any data? Or are you just expressing your opinion? Has anyone actually run a V6 on a dyno back-to-back with different octane fuels?

Believe me, if Ford could give up say 1 mpg and gain at least 7 HP with nothing more than octane and timing, they would do it without blinking an eye. The Camaro V6 is rated at 312 HP and 28 mpg. Having a Mustang rated at 312+ HP and still getting 30 mpg would be an advertising coup for Ford.

Nobody looks at what kind of pump gas was used to produce the numbers so Ford isn't basing the numbers on 87 octane because it's cheaper and fits a "budget" image. They use that fuel because they know there is nothing to gain from using a higher octane fuel.

Besides, notice the difference in the way the owner's manual treats fuel use. For the 5.0, they make a point of saying that the car will run on 87 octane but performance will be better with 93 octane. For the V6, they only recommend 87 octane. If there was more performance to be had, don't you think they'd mention it?

Bert

not sure if it has much data, but here is another thread on the subject:

https://themustangsource.com/f726/hi...epower-487261/



So, what about the guy's original question about when to shift for fuel economy on the new V6 . . . somebody else here must have some experience with that . . .

Lancel

Actually I'm not sure Ford would. They've gone on record saying they're attacking fuel economy more than anything in marketing. Look at the commercials for their latest cars, every one of them makes huge mention of the fact that it gets good gas mileage. They basically just say "It does what you expect it to. Oh, and it gets good gas mileage." I mean heck I haven't seen a single 5.0 commercial that wasn't on the internet. Plenty of V6 Mustang "31 MPG + 305 HP" commercials on the other hand.

That said, it's hard to say if they'd mention it. The technology allows it though, and to be perfectly honest I'm pretty sure it's just knock sensors telescoping to the right spark timing until it detects knocking, then backing off until it doesn't detect any. That's how it's been explained to me, after all it has no way to figure out what gas you put into it. By that grace it would get slightly more power even if the manual doesn't mention it. It's a bit of a theory I suppose, but if you think about it, the only reason it's mentioned on the GT is probably because they rated it with 91 octane and wanted you to know that the car works with 87 octane but at reduced power. The vast majority of drivers understand that putting in less than the recommended octane is hard on the engine, but adaptive spark timing solves that issue, and Ford wants you to know that it's okay.

Heck they probably only mention the -10 ft-lbs of torque with 87 because they want to give you the false impression that you can save money and get the same power by putting in 87 octane.

But as with all things, it's just a theory until someone puts it on a drag strip or a dyno with 87 octane, then 93 octane.

WhiteBird00

Not quite... there is a practical limit to spark advance aside from causing knock. The adaptive spark will advance the timing up to a set limit beyond which it wouldn't matter if you were running 120 octane. There is a point of diminishing returns with spark timing - at some point advancing the timing more will result in less power. Taken to the extreme, advancing timing too much will lead to an engine that doesn't run regardless of fuel.

What I'm suggesting is that the V6 is already running at or near its timing limit so the adaptive spark system won't advance the timing any more despite an increase in octane. The GT and Taurus (V6) manuals both mention increased performance with higher octane but the Mustang V6 doesn't... that seems significant to me.

And to keep it on topic for the OP, saving 20 to 30 cents per gallon using regular is probably more than any driving techniques will gain him.

SD6

I thought it was rated 412hp on 91 octane?

Cornezy

yup thats what I have been trying to do! thanks!

Cornezy

wait! I get less economy on the highway?!?!? how is that?!?!? maybe thats why lol cause I use the interstate like for 97% of my trips because my job and my home is right off an exit

Cornezy

wow! I'm glad I asked you guys! I always fill up at 1/2 way (old habit) so next time I fill her up Ima put in the 87...thought 93 burned longer or whatever