Fuel Consumption on the 4 cyl

[fowljesse]

Actually, the ZE IM causes less drag in the air under the hood, and... AHAHHA!
Yeah, the car with the ZE is low, and that accounts for alot. PLus it's just been rebuilt. And those figures are actually the average. The GS got 35, at best, and the ZE, 33. I think an RS could get 40+.

[SuperK]

The RS, DOHC, is capable of 40+

Mine is, at least. however, you have to destockify it a bit to do so.

I ran 40-42 on a 4 hour trip doing 65-70 the whole way, getting stuck in atlanta traffic for a while as well. I have some modifications done to the engine, but none to the body, so it's not sitting any lower or anything.

And that's without using acetone.

[Volones]

I also use the EOC method (engine off coast), and it helped me improve my mileage to 38.7mpg with snow tires installed. Now that I have my summer tires back on, I'm hoping to get just over 40mpg. These numbers are in mixed driving, at about a 50:50 ratio.

If you're not comfortable with the EOC method, by all means DON'T DO IT!
Also, if you've never tried it before, you should practice in an empty parking lot first, as I've heard of people that just turn the key off and their steering locks. Don't be that guy!

Other things that can be done are:
slow/moderate acceleration
coasting to stop sign/lights
giving a gap in stop/go traffic so you can keep a constant speed
timing stop lights so they are green when you get to them
inflating your tires to the max sidewall pressure (this is also controversial, but I feel it is safe)
slowing down to 55mph-60mph max

good luck,
Vol

[fowljesse]

Speaking of switching tires, you could get skinny low-resistance tires for better fuel efficiency.
I also do the methods described by Volones, but I cruise at 65.

[Sortin]

I also use the EOC method (engine off coast), and it helped me improve my mileage to 38.7mpg with snow tires installed. Now that I have my summer tires back on, I'm hoping to get just over 40mpg. These numbers are in mixed driving, at about a 50:50 ratio.

If you're not comfortable with the EOC method, by all means DON'T DO IT!
Also, if you've never tried it before, you should practice in an empty parking lot first, as I've heard of people that just turn the key off and their steering locks. Don't be that guy!

Other things that can be done are:
slow/moderate acceleration
coasting to stop sign/lights
giving a gap in stop/go traffic so you can keep a constant speed
timing stop lights so they are green when you get to them
inflating your tires to the max sidewall pressure (this is also controversial, but I feel it is safe)
slowing down to 55mph-60mph max

good luck,
Vol

I see nothing controversial about inflating tires to their maximum pressure. The tire, not the car, determine the maximum pressure, and that's printed right on the sidewall. Inflating to the maximum just makes sense.

If you don't do those things listed...I can't imagine you'll be getting 40+ mpg. The most I've gotten was just shy of 38mpg on a full tank (with just under 175,000 miles) so getting 40+ would be quite a feat. Of course, mine was commuting to work and home, not pure highway driving. I've yet calculated a trip like that, but I imagine if I found a semi to draft behind, I could get 40+ mpg.

[npspears]

wow, can ze Mx-3 really get 33 mpg? I mean dang. That is pretty awesome if it is true. 33 mpg in a 200 hp car.

[fowljesse]

Yeah, that's on the Freeway, with cruise set at 67, and 2 3/4 oz. of Acetone on the tank.

[Volones]

I see nothing controversial about inflating tires to their maximum pressure. The tire, not the car, determine the maximum pressure, and that's printed right on the sidewall. Inflating to the maximum just makes sense.

Some people are saying that by inflating the tire beyond what the auto manufacturer recommends, it will decrease the contact patch and make driving the car dangerous due to less control around corners and when emergency braking. I think that's total BS, but they still claim it's true.

[npspears]

Don't inflate your tires too much beyond the recommended amount or hitting bumps will feel like you hit a pothole. Believe me, it makes for an unpleasant ride.

[nate2k5]

haha, I thought the same thing about ze being aerodynamic...

he means the car that has the ZE installed itself is more aerodynamic, as he's done mods to the body to reduce drag. Haha, it's too bad he wasn't calling the engine aerodynamic. I needed a good laugh

ha

[SuperK]

ha

Best quote of the day award?
At least use two words in your posts, that way people (like me) aren't like, "wow, that's not upping your post count AT ALL!"

For example... you could have said...

"Aerodynamic.... HA!"

or...

"ICANHASCHEEZBURGER, Meow!"

but anything more than "ha". Seriously, I got an email saying, "there's a new post in the thread!"
And I'm thinking, "goody!"

...open it up....

"ha"

and I feel my morning's been wasted?




*BIG EDIT!!!!*



FowlJesse has wasted my afternoon!

SEE BELOW FOR DETAILS!

[fowljesse]

Ha

[Ryan]

So I just did a 3 hour straight highway drive, 100km/h (60mh) all the way there, and then drove about 8km each way to work and back for 5 days. 32mpg.

What should I be looking at changing up? I can think of... filters, air, fuel. injectors. O2 sensors? Drive nicer (I CAN spin the tires on my SOHC, just around corners and in 2nd and on bald tires)

[Leedeth]

To coast in a manual, put it in neutral, turn the key back, wait a second, then turn it forward. Don't start the engine. You still have steering and brakes. If you need to brake hard, then you shouldn't have been coasting. I coast with no traffic in front of me. No reason to brake, no reason for a sudden lane change. You can still change lanes without power steering.

Wait, I thought all EFI equipped cars have the injectors cut fuel when you're above a certain rpm and off the gas?

[shameem]

Wait, I thought all EFI equipped cars have the injectors cut fuel when you're above a certain rpm and off the gas?

That is what most *modern* ECMs do - if you are in gear (no clutch and no neutral) and step off gas the injectors shut off to varying degree (lower their duty cycle) to help with coasting - once it gets to idle RPM they start their default duty cycle to keep the engine at idle. ATX will be a little different (because the shift solenoids are trying to shift at the same time) - but same principle. *Some* OBD2 cars consume a bit more fuel during coasting to keep the cat from cooling off.

But the caveat is nobody knows if mx3s do that - unless we hook up an oscilloscope to the injectors and calculate the duty cycle during coasting - we will never know...

http://video.aol.com/video-detail/fuel- ... 1281397758" onclick="window.open(this.href);return false;