Gas Mileage and Shifting

[CougarGuy1802]

downshifting uses engine compression to slow you down

[Rembo]

I drive about 60% highway and 40% city and normally get around 8 to 9 L/100km (26.5 to 29 mpg) and guess I could do even better if I wanted to. I use to shift around 3000. I normally drive between 60-65mph on the highway and at that speed your instantaneous consumption is around 6.8L/100km (34.5mpg) so it helps alot to lower the average and compensate for the city drive.

Using the cruise control on flat highway will help get better fuel economy because it's steady. When you go over hills you should manage yourself and let the car accelerate while going down to get more speed at the bottom and leave the car slow down when climbing without giving more gas.

To add more on the fact that driving 55 should be better than 65, theory proves it true. In fact the drag formula involves density of the fluid (air for instance, which you can't do much about),surface exposed (so avoid big wings), the drag coefficient (once again avoid big wings or anything that breaks the aerodynamics of the car) and finally square of the velocity (V²). So in the formula going 120 km/h instead of 100 is not going to drag only 20% more, it would drag 44% more. So it pays to drive slower.

There are alot of other quick tips to help fuel econmy such as:
Driving windows downs instead of running the AC
Windows up and only normal ventilation is even better, but you could sweat on hot days
Tires to maximum pressure
less braking before cornering

Some people say they get better milage on high octane fuel instead of regular gasoline. I never tried myself but since it's more expensive is it worth it ???

We could discuss that all day. It 's only a matter of behaviour and conditions ( highway/city, average speed, temperature, etc). In fact the less you step on the gas and less it should burn. So never be in a hurry, be gentle with the pedal.

Drive every day like if it was sunday.

[EricF]

Originally Posted by work_in_progress

Oh, and we talking about v6's here?

Oh yes, mine is a V6...

[SlowCat]

In normal drive I averaged about 24mpg. When I actually tried to get good gas milage I would average 27-28mpg. The best I ever got was just over 30mpg over 2 tanks of gas. But I hated driving.

For best milage...

Around Town -
1) Light on the throttle.
2) Shift at 2K.
3) Coast as much as possible, i would even kill the car coasting up to red lights, then drop the clutch if it turned green while coasting to get going again.
4) Kill the car at every light you think will be more than 10 second.
5) If you have an ATX let the idle of the car start it moving before you give it gas.

Highway -
6) Accelerate smoothly onto the freeway, don't floor it, but also don't go super slow.
7) Always try to stay behind someone and always stay under 65. I'm not a fan of 50-55 on the freeway as I think it can be a hazard to other drivers, but will follow others going 55-65.
8) NO AC, keep the windows up & just use the blower for circulation if you can.

General -
9) Over Inflate the tires slightly, 4-6psi, but not above the tires max.
10) Make sure you're up to date on all maintenance.
11) Remove everything you can from the car, such as junk, spare tire, jack, trash.
12) Add any mods that will increase the VE of the engine, IF you can keep your foot out of the gas they will give you better fuel economy. ( such as SVT Lite + I/H/E)

[work_in_progress]

Originally Posted by AliasJerk

another thing I remember hearing about on top gear, is when you let your foot off the gas and coast while in gear the engine is actually running off of the stored kinetic energy that it has built up from accelerating

I"m not up on my phsysics, but wouldn't that still use up more gas than dropping it in 5th or N and just braking normally? Your RPM's are still high from the GRADUAL slow down, burning more gas. Side note: I love the people that downshift all the way to 1st when coming up to a light. What a waste of gas.

Hasen't that A/C myth been busted? I coulda sworn that multiple times it's been said that there's either a negligable amount of MPG loss or nothing at all, AAA tests and that Hypermiling link had something on that too.

Originally Posted by Rembo

Some people say they get better milage on high octane fuel instead of regular gasoline. I never tried myself but since it's more expensive is it worth it ???

Premuim Gas Explained //Another interesting Premium Website
Just googled this cause I was interested what Premuim gas REALLY did. Premuim can take a higher compression and heat than Regular, helping combat knocking. Only if your car has a high compression ratio would you need premium. Octane sounds super duper fancy, but just another term for anti-knock-index, NOT related to power output at all.And all those special cleaners in premuim...all quality gas has them in it. If you're really concerned buy a bottle of your favourite gas additive. Doesn't make sense to me to fill up with premuim unless you were having problems. Ethanol doesn't make sense to me either. You fill up more often, it's messing up the food markets, and it's not the solution. ND is investing waaaay to much in ethanol methinks.

One interesting random article from the Hypermiling:
Traffic Waves
A lot of thought went into this it seems. Better on gas milage too instead of the usual stop and go stuff. Wish more people would drive like this, but it just feels so wierd 'sunday driving' 7 days a week. So sloooooow.