Convinced my car is sucking gas harder than it should.

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ShawnD1

Lifer
May 24, 2003
15,987
2
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I think most of those hypermiler types with i4s in that range use decent-quality 5w20 oil, which makes a small but real improvement in fuel economy over 10w30, and the operating temperature in Washington state should be no problem for it.
Haven't civics used 5w20 for over a decade? 10w30 is too thick. It can't fit those tight vtec tolerances, yo.

The auto definitely penalizes things a bit, particularly being a 4-speed. Those things typically have your motor turning over at a higher rpm to go the same highway speed than 5th gear in an econobox manual.
I don't know about year 2000, but right now it's the opposite of this. In the Corolla, Civic, and Impreza, the automatic top gear spins slower than the manual even when the manual has more gears. I think it was only the 3 speed automatics that spun really fast like that.
edit: I guess not. Manual was slightly better that year. Auto should get 24/32
http://www.fueleconomy.gov/feg/compx2008f.jsp?year=2000&make=Honda&model=Civic&hiddenField=Findacar



It gets even worse if you're in a situation where the thing keeps shifting from 3rd to 4th (you may have seen this going up a sustained incline).
Sounds like my car. Gear 4 is waaaay up there. Very slow spinning, has no balls at all. If a butterfly in China flaps its wings, it drops from 4 to 3.



Mythbusters also showed that a dirty car got worse fuel economy than a clean car, but a slight but real amount. Hilariously enough, once it was covered in golf ball shaped clay, it improved further :p
Maybe this idea could replace "inflate to sidewall" as a way of improving fuel mileage :awe:


Oh yeah, another weird thing that I don't recommend really, but I have a friend who delivers stuff for an oil company, he drives an old VW hatch, he actually got narrower tires and improved his fuel economy a bit. I don't necessarily think that's a great idea considering the tradeoffs that has, but it's another crazy thing people do.
This would theoretically make the car accelerate faster as well because it reduces the amount of rotational inertia. It's similar to making the car lighter. Rotationally lighter.
 
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Arkaign

Lifer
Oct 27, 2006
20,736
1,377
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Yeah the 4-speeds were spin-happy. Not as bad as the horrendous 3-speeds, but still bad. The newer 5-speed autos are a huuuuuuuuuuuge improvement :)
 

disappoint

Lifer
Dec 7, 2009
10,132
382
126
Oh yeah, another weird thing that I don't recommend really, but I have a friend who delivers stuff for an oil company, he drives an old VW hatch, he actually got narrower tires and improved his fuel economy a bit. I don't necessarily think that's a great idea considering the tradeoffs that has, but it's another crazy thing people do.

I don't see what's weird or crazy about reducing rolling resistance. Even car manufacturers do this. It improves fuel economy at the cost of handling.
 

TridenT

Lifer
Sep 4, 2006
16,800
45
91
I find out tomorrow how well my car did with the tires pumped up to about 38PSI and 75% of highway driving and 25% city.
 
Mar 11, 2004
23,250
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I think the only logical step here is to buy a new transmission, and you'd better make sure that its geared specifically for a single hill, this way you can get to the gym and work out.
 

Bignate603

Lifer
Sep 5, 2000
13,897
1
0
I think the only logical step here is to buy a new transmission, and you'd better make sure that its geared specifically for a single hill, this way you can get to the gym and work out.

Only do this if you know more than a korean automotive engineer about fuel economy, otherwise you'll screw it up.
 

hanoverphist

Diamond Member
Dec 7, 2006
9,867
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People usually pad their actual MPG...

i dont. when i got my 98 civic (same motor as the EX i think) i got 28.7mpg. a good tune up, new fuel pump and putting tires to listed psi and it went up to 34mpg. i regularly get 34 on it, depending if im driving it normal or like im on a track. if im being a douche driver for a whole tank the mileage drops under 30mpg again. right now it doesnt go anywhere, since i blew the head gasket in it.
 

TridenT

Lifer
Sep 4, 2006
16,800
45
91
Pumped tires up to 38 PSI. (Up from 26-28 PSI (I think they deflated over time because I usually do 29-30)) I got 33.9mpg with Portland to Seattle trip + about 90 more miles of various city/highway driving. (Those trips regularly get me 28-31mpg)

I am looking forward to my next Seattle to Portland. I want to see my true highway gas mileage. :awe:
 

Arkaign

Lifer
Oct 27, 2006
20,736
1,377
126
I don't see what's weird or crazy about reducing rolling resistance. Even car manufacturers do this. It improves fuel economy at the cost of handling.

It generally works best when left to professional engineers though. Reducing traction for the pursuit of ~1% fuel economy and making the vehicle less safe to operate is a poor trade off.

Even in my current car, which came with stock LRRs, they were a damned death hazard in the rain, so I dumped them asap and got all-seasons which produced a dramatic improvement in handling and braking performance, with no notable difference in fuel economy at all.
 

pimpin-tl

Senior member
Jan 24, 2010
293
2
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Our 2008 Civic EX-L gets 38mpg highway. The other cars a 09 Acura TL 32 highway, and 2011 VW GTI 32 highway.
 

MovingTarget

Diamond Member
Jun 22, 2003
9,002
115
106
Meh, that sounds about right for real-world driving conditions. Honda Civics are decent cars, but they aren't anything magical.