Fuel question

[Fiat500USA]

unclelaverne wrote

I'll probably fill up once a week or so.  The difference for me will be about $10 - $12 a month.  I'm not made out of money but if $10 a month becomes a concern for me, I should think I better be taking the bus.

I got a chuckle out of that

It's true, you may not miss 5-10 lbs.ft  of torque in a car with 200 lbs.ft in everyday driving, but in a car with just 98 lbs.ft, that's a different story. Personally, I'm paying for and want the 98 lbs.ft Fiat 500 not the <93 lbs.ft version.

To each his own, and I guess it's a matter of priorities. Some days I might drive with the sport button off, but when I press it, I want it to work.

[Gavin]

I'll be filling up once a month...probably can afford the 24 bucks a year for 2 years...then I go electric and never buy gas again :)

So maybe my 24 bucks will help those poor oil countries...hopefully they put that money toward alternative energy...cause in 20 years almost nobody will be buying gasoline...

Gavin

[CaliberSRT4]

MrJones wrote

Fiat500USA wrote

Besides, on a 10 gallon tank, it's only $2 ...

I suppose if you're made of money you won't miss the nearly $300/year.
As far as I can tell, for most driving conditions you won't get any benefit from using premium fuel. (unless you own a lot of stock in the petroleum industry)

I didn't check on the figure, but assuming the price difference for filling up with a tank of premium is $2, then $300 per year would be 150 fill-ups. At EPA combined, that's 50,000 miles per year. I guess you would be made of money to drive that much per year, or else have a job that involves a lot of driving and probably pays for your gas anyway.

Not sure what you are basing your second statement on. Fiat recommends premium fuel, and at the moment we have no data on exactly the differences in power and fuel consumption. Also, "most driving conditions" can have a very different meaning from person to person. For example, the majority of one's driving could be occupied by freeway cruising, city driving, or rush hour stop and go. Besides the driving conditions, the person's driving style and preference toward lower cost or higher performance would help determine fuel choice.

Of course, you can also switch between the different grades of gas at will. So it's not like you have to pick one and use that 100% of the time. Feel free to experiment.

[MrJones]

You are right about the extra cost. I hastily made a miscalculation. I am sorry. It should be more like $80 more per year. (10,000 miles/year; 10 gal capacity; 33 combined mpg; $0.26 current premium fuel cost over regular). I will double check my numbers before I post next time. Still, I can think of a lot of things I would rather spend my money on than making petroleum companies richer.

My second point is not based on Fiat, but all vehicles in general. Based on the little research I have done on the subject (and I admit, it is not a lot), "most driving conditions" is exactly what you have stated: "freeway cruising, city driving, or rush hour stop and go." I hardly think the average driver will notice a difference in performance. Of course, your results will vary and you are free to use whatever fuel you like.

@Gavin: "So maybe my 24 bucks will help those poor oil countries." Those people don't see hardly any of that money. Do you think it has helped the people of Libya, or Nigeria, or Colombia? The ones making the money are shareholders and CEOs of BP, Shell, etc.

[PE#454]

CaliberSRT4 wrote

...Of course, you can also switch between the different grades of gas at will. So it's not like you have to pick one and use that 100% of the time. Feel free to experiment.

Are there any noticeable or "harmful" effects to mixing? If you do so, is it best to do so with a near-empty tank? That would be alternating more than mixing. Mixing would be like topping off a half-tank full of regular with premium, or vice versa. I wonder what the effects would be either/both ways?

[Gavin]

MrJones wrote

@Gavin: "So maybe my 24 bucks will help those poor oil countries." Those people don't see hardly any of that money. Do you think it has helped the people of Libya, or Nigeria, or Colombia? The ones making the money are shareholders and CEOs of BP, Shell, etc.

which is why I'm going electric as soon as either the Fiat 500 EV or Volvo C30 EV is for sale...I hope those countries have prepared for a quickly decreasing oil revenue...sadly I doubt they have and I doubt the people saw any of the money anyways...

So in some ways the people won't see much change, just the sheiks and robber barons...who already have more money than they will ever need for 1000 lifetimes...

Gavin

[prima 109]

No not really.  What you could do is alternate between octanes at each fill up or use 89 octane fuel.  If Fiat says it's ok to run reg (87), then wouldn't be concerned.  I plan on mixing and I don't expect any problems.

[Giallo Edizione]

Mixing doesn't matter. The beauty of the variable timing and computer control is the engine knows what's coming through and adapts. So you can fill with 87 for long trips on the highway and 91 or even 93 if you want blast around town and any mixing won't be a problem.

[sketch]

Sacred Bezel wrote

I'm not expert ( on this or much else for that matter) but the lore I read is that higher octane will give better mileage per gallon ( think about it-if you get more power per gallon then fewer gallons needed to do the same work), but not enough to make up for the difference in cost over lower octane fuels. There is a fun-factor in the pricing spread.

In the interest of clarity, this is indeed true, but only for engines which recommend (and are designed to run on) higher octane ratings, like the 1.4 MultiAir in the 500.  A higher octane rating basically means a higher resistance to autodetonation (knocking), which is important in high-compression engines like the 1.4, and especially important in forced-induction engines (like in the Cooper S) which essentially operate by creating high compression.

You'll get more power and better efficiency out of a high-compression engine like this one using the recommended 91 octane, but if your car recommends 87, there is no benefit to using a higher octane rating.

[Giallo Edizione]

sketch wrote

Sacred Bezel wrote

I'm not expert ( on this or much else for that matter) but the lore I read is that higher octane will give better mileage per gallon ( think about it-if you get more power per gallon then fewer gallons needed to do the same work), but not enough to make up for the difference in cost over lower octane fuels. There is a fun-factor in the pricing spread.

In the interest of clarity, this is indeed true, but only for engines which recommend (and are designed to run on) higher octane ratings, like the 1.4 MultiAir in the 500.  A higher octane rating basically means a higher resistance to autodetonation (knocking), which is important in high-compression engines like the 1.4, and especially important in forced-induction engines (like in the Cooper S) which essentially operate by creating high compression.

You'll get more power and better efficiency out of a high-compression engine like this one using the recommended 91 octane, but if your car recommends 87, there is no benefit to using a higher octane rating.

Agreed.

[sjmst]

Other Fiat competitors, and their respective 2011 city/highway fuel mileage ratings, include the
Chevrolet Aveo (27/35),
Honda Fit (27/33),
Mazda2 (29/35),
Mini Cooper (29/37),
and Toyota Yaris (29/36).

[Leo Pagliei]

If your car calls for premium, use it. The primary difference between hi and low octane is the fuel burn rate. The higher the octane, the slower the fuel burn rate...or time it takes the explosion to take place. The reason an engine that calls for hi-octane knocks when lo-grade fuel is used, is that the fuel fires too quickly...while the piston is still on the way up in the engine, thus trying to push the piston back where it came from before it reaches the top. Normally, before it reaches the top, the burn begins, but the burn is completed when the piston reaches its downward progression, increasing power, and running smoothly. Enough hammering on the piston towards the wrong direction...knocking, can actually bend the connecting rods and seriously hurt the engine...and at minimum, lower the fuel mileage significantly.

[Leo Pagliei]

If your car calls for premium, use it. The primary difference between hi and low octane is the fuel burn rate. The higher the octane, the slower the fuel burn rate...or time it takes the explosion to take place. The reason an engine that calls for hi-octane knocks when lo-grade fuel is used, is that the fuel fires too quickly...while the piston is still on the way up in the engine, thus trying to push the piston back where it came from before it reaches the top. Normally, before it reaches the top, the burn begins, but the burn is completed when the piston reaches its downward progression, increasing power, and running smoothly. Enough hammering on the piston towards the wrong direction...knocking, can actually bend the connecting rods and seriously hurt the engine...and at minimum, lower the fuel mileage significantly.

[Mr500]

I bought a new Fiat 500 Pop two months ago and reviewed all the information I could find about using the lower 87 Octane gas.  After a little hesitation and a talk with my Dealer I decided to try the lower Octane gas.  Absolutely no problem - no knocks, no hesitation, no difference in performance noted at all.  Of course I live in Florida highways are flat,  and speed is a minimum of 70 mph.  But even with four adults in this little car performance was the same.  Of course, I do have the 5-speed and know to get this car really rolling in the performance category you need to hit at least 3000 rpm.  
In my gasoline research to boost the octane rating up on most brands they usually use more alcohol (ethanol). Almost all gasoline can have up to 10% alcohol in Florida by law.  Alcohol may boost octane ratings but it actually delivers slightly less miles per gallon.  So mpg on regular or premium is going to be about the same and my little research is proving this to be true.  
However, I have not pulled the spark plugs yet to check how the burn looks on the electrodes.  I planned to use a high grade premium like Chevron or Shell every third or so tank to keep the engine and plugs clean.  These two brands have the best cleaners mixed in their gas blends from independent labs I checked out.  
It also use to be true that premium was only 20 or 30 cents more per gallon.  Not anymore, I have seen price differences of 60 cents or more in some Tampa area stations.  One interesting surprise item noted in my gas research is how fast gas can degrade (lose octane value) in about 3 weeks.  So if you fill up every couple weeks I don't see any problem using regular but if the car sits for longer periods than  premium would be the better option.    I hope this information helps.