Jump to content

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

Improve my gas mileage

#1 User is offline   ronblanford 

  • Topic Starter
  • Group: Gold Member
  • Posts: 2,235
  • Joined: 24-August 02
  • Location:Poway, CA
  • Country: United States
  • Interests:J.R.R.Tolkien

Posted 20 July 2003 - 03:42 PM

My S is my daily driver. My commute is about 40 miles each way, mixed surface streets and freeway. Depending on my mood I will sometimes drive casually and sometimes aggressively, and generally vtec at least once a trip.

I calculate my mileage almost every fill-up. It usually averages out around 23 mpg. This has been for casual interest, and I've never cared much to improve it, but when I heard people on this forum talk about getting 30 mpg or better it made me wonder how they do it. Out of curiosity, on my most recent tank I decided to see just how much better I could do. It turns out not very much.

So maybe you guys can give me pointers. I figured the most important thing would be to keep the rpms low and accelerate very gently. I began shifting below 3500 rpm, and cruising as close to 2500 as I could get. I never really pressed on the accelerator, just caressed it as I entered each gear and let the engine take its own time getting up to the next shift point. All this had the effect of making it feel like driving a semi: accelerate gradually for a couple of seconds and shift, accelerate and shift, okay I'm across the intersection now in third gear. Accelerate and shift, accelerate and shift, accelerate and shift, and I'm in sixth going about 45. This has all taken about 30 seconds and the car behind is tailgating. Don't even think about vtec. Approaching every corner and red light, put it in neutral and coast.

That felt like the longest week of my life. Driving lost all its excitement. The car was just transportation, no different than my old VW Rabbit. And guess what? When I finally was able to fill the tank, at 270 miles, it took 10.5 gallons, for a measly total of 25.75 mpg. Okay, it was better but not the dramatic improvement I hoped for. What a disappointment. But now that I've done it, I won't ever again feel bad about not trying for better mileage, since I can't make it that much better anyway. I'm driving for the fun of it again and loving life.

So what did I do wrong, aside from thinking it mattered in the first place?
Ron Blanford (http://www.blanford.com)
Posted Image

#2 User is offline   RM 4 2 

  • Group: Guest
  • Posts: 929
  • Joined: 21-February 03
  • Location:Fairfax, VA
  • Country: United States

Posted 20 July 2003 - 04:52 PM


I did the same, bro. I even took off my spare tire(keep the tools, though) and fill up only half a tank!!! I still got 26-28 MPG at best, all medium trafic city VS. 21-22MPG with spare tire and full tank of gas.

My answer is "HALF TANK ONLY PLEASE!!"

Maybe those 30MPG and up are the mileage from highway?

#3 User is offline   ralper 

  • View gallery
  • Group: Gold Member
  • Posts: 24,701
  • Joined: 23-August 02
  • Gender:Male
  • Location:Randolph, NJ
  • Country: United States
  • Interests:None, just a boring accountant.

Posted 20 July 2003 - 05:30 PM

I keep extensive records of my milage, and I can tell you from my experience that at 25 to 27 mpg in mixed driving you are probably doing as well as you can. I have only been able to top 27 once and that was exclusively freeway miles.

In general I get about 21.5 mpg in mostly rush hours but mixed driving. Just enjoy the car. The difference in the mpg is not significant. You bought it to enjoy it.

I keep track because I like to know.
New Jersey's favorite son

2002 Honda S2000 Sebring Silver/Black
1987 Bertone X-1/9 White
2012 BMW 328i Sport Edition 6 Speed Manual/Navi Imperial Blue/Black
2012 Honda CR-V Urban Titanium (Whatever that is)
2009 Acura TSX Tech Package Vortex Blue Pearl
2006 Honda Civic Si Navi Alabaster Silver
2005 Honda Civic EX Special Edition Magnesium/Black

#4 User is offline   jojipoji 

  • View gallery
  • Group: Guest
  • Posts: 1,642
  • Joined: 09-August 02
  • Gender:Male
  • Location:West Hartford, CT
  • Country: United States
  • Interests:Beer, sports, cars and spelunking

Posted 20 July 2003 - 05:58 PM

Get a vafc and it will lean out your factory set air fuel mixture, which is set at a very rich mixture. Of course it will cost you lots of money to buy the vafc and tune it, which makes my suggestion pointless because you will probably vtec even more negating all of the gains in gas mileage, making this post irrelevant except for me to post more pointless and wise ass suggestions.
2009 GTR
2008 Yamaha r6
2008 evo mr fp green
"we all die sooner or later, might as well live like today is our last"

#5 User is offline   xviper 

  • Group: Guest
  • Posts: 37,303
  • Joined: 15-March 01
  • Gender:Male
  • Country: Turkmenistan

Posted 20 July 2003 - 06:01 PM

I think you have to report either city mileage or highway mileage. Doing a combination mileage is somewhat pointless because every individual will have a different combination of city/highway.
I'm guessing that those high numbers you have seen are from those who have taken a highway trip from one city to another.
For example, when I reported getting 39.9 miles per Canadian gallon, this was fueling up at the edge of the city, and immediately going out and driving on the highway till I fueled up again. Speeds rarely went below 55 mph. And this is with normal shifting up through the gears and some passing.
In the city only, I was getting about 26 (Cdn gallon).
The trouble with your calculation is that even though you do a 40 mile X 2 commute, you have all that stuff before, in between and after, where you are shutting off the car, going through traffic with lights, stop signs, parking lots, idling, etc. All these things can kinda screw up your car's apparent mileage when you compare to others who report mpg.

#6 User is offline   meriggi 

  • Group: Guest
  • Posts: 1,156
  • Joined: 25-December 02
  • Location:Hill Country, Texas!
  • Country: United States
  • Interests:Racing, Boating, Snowboarding

Posted 20 July 2003 - 06:28 PM

If we can VTEC and still get 23 mpg, why would you even want to get more boring miles to the gallon!!!
Just my smart-ass remark!
Arceo 18" whls w/Pirelli's

#7 User is offline   QPhox4 

  • Group: Guest
  • Posts: 429
  • Joined: 24-April 02
  • Gender:Male
  • Location:Panama City Beach, FL
  • Country: United States
  • Interests:Fishing the Gulf, enjoying being retired!

Posted 20 July 2003 - 08:33 PM

Hey, I'm really sorry that I get 29+ mpg average for 14 months and 12,000+ miles. I'm just unfortunate that I don't have a freeway nearby, where I can blast along at 75 or more. Of course, I don't have many stop lights around town either (I actually tend to avoid them by going a bit out of my way.) I think my mileage is pretty good because the major part of my commute is between 45 and 60 mph. I once read that the best mileage is attained at 30 mph (that was about 35 years ago in drivers' ed), but I feel that the old double nickle is a pretty economical speed also. I had two previous vehicles that had an instaneous mileage read out, and I guess I just got used to doing things to keep the number high. Maybe being at 4500' altitude also gives me less wind resistance ;) I definitely don't practice driving like you've used as your example. Maybe my car is just a jewel!:LOL:
'02 Suzuka S2000
'98 Suzuki VS800
'89 Chevy C3500
Mach 2 aint near as fun as VTEC!

Vets! Served Proudly? Get your's at geckocountry.com/milgraphics.htm
page 10

#8 User is offline   tritium_pie 

  • Group: Guest
  • Posts: 4,541
  • Joined: 17-May 03
  • Gender:Male
  • Location:LA
  • Country: United States

Posted 20 July 2003 - 09:10 PM

when I was poor and my CRX was my daily driver, I became fanatical about trying to eek out as much mileage from my car. call it a poor boy's hobby.

my overall average is 38.47 MPG in a '89 Honda CRX, with 172000+ miles that I've had since April of '00, bought with 137387 miles on the odo. I almost always filled up when the tank was near empty, kept the receipt, and was fanatical about putting everything into an Excel spreadsheet. by filling up when the tank was near empty each time, this allowed me to more easily divide the # of miles driven by the # of gallons I had to put in, and it didn't make the graphs all screwy. (although apparently, having a nearly empty tank means your pump is more likely to siphon up the gunk at the bottom of the tank, and your fuel filter will have to work harder. so if you're going to do this, pick a line on your digital fuel gauge, and fill up EVERY time it reaches that line)

the more money I started to make, the less concerned I was about fuel economy, so my average MPG used to be higher. and since it's next to impossible to figure out Hwy -vs- City miles, I'll just say that they were about 50/50. I can't really know for sure though. I kept pretty good notes tho on my spreadsheet whenever I took a long highway trip.

I even did an experiment using 89 octane for some time, and saw ZERO benefit. it only cost me more $.

I filled up almost exclusively with Chevron gasoline, 87 octane.

here's how I did it:
1) when I anticipated that I would be having to come to a stop, or even to slow down, I put it in neutral and coasted. sometimes for a long time.

2) downhills, I often coasted. THIS IS VERY BAD-- if your brake fluid heats up and starts to boil, your brakes can fail. (Thx Car Talk guys on NPR for this bit of wisdom! :) ) I did not know better. now, I put it in 4th and take my foot off the gas. I don't know if this uses more fuel than just coasting (my suspicion is it does) but it is a heck of a lot safer.

3) accelerate slowly. no, even more slowly than that.

4) draft behind big semi trucks. (NOT recommended, else your S will be rock chip'd repeatedly) on top of that, some of them get kinda freaked when they know there's a car right on their rear, and they can't see it because you're so close. how close? close. I just kept in mind that I could brake faster than the semi so I just kept enough room to have enough time to brake. when I used to have a car with a sunroof (not my CRX), by putting your hand out the top, you can feel the wind resistance change. then you know you're really drafting. in an S, very easy to do also. but remember: rock chips.

5) get into as high a gear as possible in the shortest amount of time without bogging your engine down.

I stopped keeping track of my mileage in January when I realized I just didn't care anymore. if anyone is interested, I'd be happy to put a copy in a Yahoo briefcase for anyone to download. it's pretty rough-- just notes and graphs for my own benefit, but if you're curious I'll be happy to share it. just let me know.

#9 User is offline   Ron Jeremy 

  • Group: Guest
  • Posts: 685
  • Joined: 06-August 01
  • Location:Sooner Country
  • Country: United States
  • Interests:Women, beer, cars, golf, women

Posted 21 July 2003 - 08:45 AM

I normally get around 21 or 22 mpg with city and hwy driving. Did the same thing about driving like my grandmother and only got around 25 after that. Then took the car on a road trip to GA/FL and got on average 29 to 30 mpg.
Think I'm going to take my spare out too and see what happens.
'02 Sebring/Red
Lucid Door and Rear Speakers
K&N (That's about it)

#10 User is offline   Karl O. 

  • View gallery
  • Group: Gold Member
  • Posts: 759
  • Joined: 28-March 03
  • Location:Valdosta, GA
  • Country: United States

Posted 21 July 2003 - 11:13 AM

I got a little over 31 mpg once, interstate driving @ 65 MPH, cruise on, top up, a/c off (it was chilly).

Ordinarily I get in the low 20's with A/C and a little VTEC'ing here and there. I was getting 24 or 25 mpg before summer rolled around and I didn't have to run the A/C all of the time.
'15 TLX, 4 banger
'13 TSX Sex Wagon
'01 S2000

#11 User is offline   svatne 

  • Group: Guest
  • Posts: 293
  • Joined: 08-December 02
  • Location:Nevada City, Ca
  • Country: United States
  • Interests:runner, computer/digital photography buff

Posted 22 July 2003 - 08:40 AM

One of the things you need to do to get really good milage is to drive only on the freeway LOL
I have gotten 36 mpg two different times driving 120 miles on freeway with cruise control set at 68 - an not passing, etc. It works, but boy is it borying!!
"Heaven for the climate, Hell for the company"

1974 Alfa Romeo Spider
1994 3000GT
2003 S2000

#12 User is offline   simioen 

  • Group: Guest
  • Posts: 564
  • Joined: 25-November 02
  • Location:Lewsville
  • Country: United States
  • Interests:Computers and my Gal!

Posted 22 July 2003 - 09:23 AM

I get about 25 MPG on the highway. i gues I :rev: too much :) heheheh :eek3: :eek3: it's so worth it!
--My baby's--
1. 5'4''
blonde, blue eyes!
2. '03 suzuka blue!!!

Ain't life great!

#13 User is offline   negcamber 

  • Moderator
  • Group: Former Moderator
  • Posts: 8,822
  • Joined: 04-July 01
  • Gender:Male
  • Location:Jacksonville, FL
  • Country: United States
  • Interests:Autox and flying my sailplane

Posted 22 July 2003 - 10:12 AM

I actually found that my Comptech CAI improved my mpg. It was not a huge increase, but it went from averaging around 20mpg to 23mpg for city driving (full traffic driving with many stop lights, rarely above 45mph).

My highway mileage increased as well. Before the cai the best I'd seen was 28mpg. After it was installed the best has been 33mpg. I usually run 70-80mph on the highway.
Posted Image R.I.P. Red_MX5...I will miss you my friend.

#14 User is offline   lanbrown 

  • Group: Guest
  • Posts: 1,456
  • Joined: 31-March 01
  • Location:Farmington Hills
  • Country: United States
  • Interests:Motorcycles, Computers and Cars

Posted 22 July 2003 - 10:16 AM

I try not to keep the engine below 3000 while cruising. There is just no power down there and it feels like you are lugging the engine, which is not good.

I can get 30MPG on the freeway, not in the city though. Changing to synthetic will also boost your mileage by one or two MPG.
'01 Black/Black S2000 - Dark Fusion
'97 CBR1100XX Black of course
'99 CBR1100XX Black again
'00 RC51 Not black
'02 Daytona Silver

Posted Image

#15 User is offline   VTECS2000 

  • Group: Guest
  • Posts: 3,138
  • Joined: 15-March 03
  • Location:Ravenna
  • Country: United States
  • Interests:going fast, running from cops

Posted 22 July 2003 - 10:50 AM

6th gear.
Member, CNA
Member, USO
Member, S2KD
Member, AWA
Rocket Scientist 2

President of the Alleyway

Official Posted Image

#16 User is offline   pjkwong 

  • Group: Guest
  • Posts: 1,268
  • Joined: 23-May 02
  • Location:EB
  • Country: United States

Posted 22 July 2003 - 10:58 AM

I drive like the way Ron drives it.
And i do get a tab over 25mpg.
But i vtec once each trip i make in it.
So in 20miles of driving i vtec about 3 times.
And still get 270miles a tank or 10.4-11 say.
03 Suzuka
Clear side markers
Speed STB and Xbrace
Spoon mag. plugs, rad cap
amuse dual exhaust

#17 User is offline   bricktop 

  • Group: Guest
  • Posts: 1
  • Joined: 16-July 03
  • Location:SAN
  • Country: United States

Posted 22 July 2003 - 12:28 PM

Anybody ever heard or seen the diagram for specific fuel consumption/RPM?

It looks like a flat U (sort of) and with that you should be able to get the RPM's for minimum fuel consumption for those boring freeway drives... might as well get some gratification by saving fuel.

#18 User is offline   ronblanford 

  • Topic Starter
  • Group: Gold Member
  • Posts: 2,235
  • Joined: 24-August 02
  • Location:Poway, CA
  • Country: United States
  • Interests:J.R.R.Tolkien

Posted 23 July 2003 - 11:29 AM

Thank you. All that everyone has said here comforts me. On my subsequent tank, driving somewhat more like a maniac than a grandmother, I got 24.3 mpg. It did include a bit more freeway than usual, so next time I take a long trip I'll definitely try to measure that portion independently.

#19 User is offline   koala 

  • Group: Guest
  • Posts: 7,730
  • Joined: 29-November 02
  • Gender:Male
  • Location:Calgary, AB
  • Country: Canada

Posted 23 July 2003 - 11:35 AM

You'll find the best way to improve gas mileage in the city especially is brisk acceleration up to cruising speed.

If you drive like a granny, your gas mileage wont be any good either.

BMW did a big study on this a while back and they found this to be true.

'16 VW Golf R | '14 Mercedes-Benz GLK
'04 S2000 (Grand Prix White / Black-Red) - Picked up Mar 17.04 [ Pics ] - Sold Mar 19.07
'01 S2000 (Silverstone / Black) - Traded in Dec 9.03

Ads by Google   S2KI

Share this topic:

Page 1 of 1
  • You cannot start a new topic
  • You cannot reply to this topic

1 User(s) are reading this topic
0 members, 1 guests, 0 anonymous users