iamhomin

Considering one gallon weights less than 5 pounds, does those extra 30~35 pounds make THAT much of a difference?

sauceman

They will somewhat, but it depends if you're willing to stop every 100 miles or so to fill up, lol.

Belzebutt

On an automatic, should you also put it in neutral when coasting? They don't seem to be as friendly for going in and out of neutral smoothly...

sauceman

For as far as I remember, it wasn't a problem shifting in and out of gear on my auto Accord. When I came back into gear though, I rev-matched as I shifted back into D4 to ensure the smoothness.

iamhomin

By the way, one stupid question.

My cruising on neutral, you would have to do a neutral drop for a 6MT right?

sauceman

No?..

I'm not sure I understand what you mean...

iamhomin

Okay, say you're traveling at 70mph when the RPM is at a 3k.

In order to cruise on neutral, don't you have to shift back down to neutral, which will result in a "neutral" drop?

sauceman

Yes, but that is not a neutral drop.

A neutral drop is when you're in an AT car, and you rev the car in neutral at a stoplight, then slam it into drive and screech your way down the highway. Kinda hard on the tranny.

But in your case, as long as you rev-match your way back into drive, or into gear there would be but very minimal wear to the drivetrain. Nothing out of the ordinary.

gogozy

how do i rev-match in AT??? thanks !!

biker

Same as with an MT - raise the RPM level in neutral to where the car would be had it been in D and then put into D.

Dan Martin

jpooncanada

Glad to hear that 70 mph (112 km/hr) is still good for 5AT. I will be driving everyday on the busiest Toronto highway (401) in my new TSX starting Wednesday. I bet if I drive 55 mph (87 km/hr), I will be honked all the way for an hour throughout my drive... because if that's the case, I will then be driving even slower than the slowest truck on the highway and it will be too dangerous to do so.

Thanks for the great tips! Also happy that TSX has its power but it is also pretty fuel economical as comparing to other luxury sports sedan.

Jac

sauceman

Glad to hear they are of use once in a while.

BTW, even though the optimal speed is 55mph, you definitely should be driving no slower than the speed limit, if not for the sake of being a total annoyance to all other drivers

Choose your road for economy testing. In Ontario, most secondary roads have a 80kph speed limit, so 90kph shouldn't be unrealistic speed.

cpurick

This is an interesting article, but I can't say I agree with everything it says.

Proper downshifting causes less wear and tear than braking.

Coasting is very fuel efficient, but be aware that it is frequently illegal.

Most of the time cruise control saves gas over hoofin' it.

Use the highest tire pressure that applies to your driving conditions.

Your car does not need a prolonged warm-up, but when it's cold you should give it at least 30 seconds before touching the gas.

"To keep the heat inside the hood, it is good to insulate it. (will be discussed in the cold weather section) This is especially true with most Hondas since they have engines that don't produce much heat. Keeping the engine bay hot will let parts like the exhaust and cat do their job right, the O2 sensor will be able to command a more accurate air / fuel mixture. Also, and this goes against the laws of performance, but the more the intake air is hot, the less dense it is, so the ECU will adjust the ratio and end up needing less fuel. You will slightly lose power this way, but also save up on gas."

This is not just incorrect, it's also dangerous. Heat is the enemy of everything under your hood, but it's a necessary byproduct of combustion and friction. If a Honda generates less heat than other cars it's a testament to how efficiently the drivetrain converts fuel energy into motion. Unless you're operating in arctic conditions you don't want to contain any heat.

The ECU will maintain the proper fuel-air mixture all the time. If you want to use 2% less fuel, then lift your foot and let 2% less air in.

Air conditioning costs the same amount of power whether you're accelerating or not.

Fuel comes from underground tanks that are not subject to diurnal variation. If you pump your car full of cool gas in the morning and let it sit in the sun, the gas will expand and you might even lose some as a result of venting. Your best bet is to avoid "topping off" your tank.

If you fill up at night, you will reduce the surface area inside your tank that might be subject to condensation as it cools at night, which could result in your fuel becoming contaminated with atmospheric moisture.

When driving in a really stiff headwind or tailwind, consult your trip computer. Making adjustments to your speed can dramatically affect your fuel mileage.

"Drafting" too closely behind other vehicles is both dangerous and inconsiderate.

psteng19

I'd like to add a few thoughts as well.

Skinnier tires have less rolling resistance, which is better for fuel economy.
Different tires have different characteristics (tread design, materials, size, weight) that give it better mpg than others. Do some research.
I also run at a few psi higher than recommended, enough so that it wouldn't cause uneven/additional tire wear.

Lightweight rims for less unsprung weight at each corner will require less power to start rolling as well as stopping. Better for quicker and easier acceleration (use less gas to start) and braking (save brake pads and rotors), as well as overall handling.

To see a measurable gain in gas mileage by drafting, you would have to be dangerously close to the vehicle in front.
Do NOT do it. It's not worth the risk.

In addition to using synthetic oil, using a lower viscosity means there is less resistance inside the engine. Don't deviate too much from the recommended though. Use the right oil weight for your climate. The purpose of oil is to lubricate and protect the engine.

Anything object that protrudes from the exterior of the car will create unncessary drag (antennas, flags, ornaments). Remove it.

Finally, weight reduction does not always have to come from the car.
Go on a diet

feliz

I recently read where if everone in the US drove the speed limit they could be self sufficient in fuel and the price of gas would be half what it is now.

I'm only posting this for interest sake, not advocating it. I mentioned this on another forum and really took a beating for trying to take away peoples civil rights, freedom etc. I guess the same could be said for a lot of countries, not just the US!!

psteng19

Maybe if we get rid of SUV's too

feliz

That would do it as well!! Guilty as charged.

vidgamer

I'd like to see more proof of this. This just sounds like one of those things that someone comes up with because it sounds good, it gets repeated, and all of a sudden everyone believes it! No flame intended. It's hard for me to get worked up over highway speeds because that's where most cars are going to get the best milage.


A couple of my coworkers said the same thing as others did here -- you don't have to be real close to the semis to still get a lot of the effect. So, sure, don't get too close, and you still may get some benefit. Most of the time, I have my own target speed, and semis aren't exactly the safest things to be near at any speed or distance , so for myself, I don't go out of my way to do this often.

If you're talking about drafting off of another car, I completely agree. I see that as pointless as well as dangerous.


I seem to be getting just over 25mpg whether its highway or city. I'm pretty happy with it, although, I think I should be doing better when 1/2 of the tank is highway....

feliz

I actually agree and hesitated to even post the comment but did it for interest sake. I remember reading years ago if you gave a monkey a typewriter, a computer now days, he or she would eventually type every piece of literature know to man. It was probably 40 years ago I first read that and have seen or heard it several times since and always wonder what basis the person that originated the remark had to make it!! Sorry to get sidetracked, it comes with senility.

sauceman

cpurick, this article was written two years ago and based on my own experience of driving only.

It does need to be updated and I will do so when I have some time for it. I will also be discussing some of your points, some others I will be arguing against.

As for the "dangerous" driving techniques, I seem to recall having mentionned at many different parts that if it was dangerous (depending on the situation and environment conditions) then don't do it. I really don't see why such an issue should be made of it as this is an article talking about the theory of what can be done to get the best mileage.

blktsx23

Great post that helped alot!!

pearltsx2007

I've got a question. What do you know of the Fitch Fuel Catalyst?