Honda Car Forum

What are you getting around town in your Civic? What's considered
"normal" for gas mileage? My son says he's getting around 17-18 mpg with
a/c use and 17's mounted as wheels, and a fart bomb exhaust ('99 Civic
EX coupe). As we didn't mount the wheels, I am guessing the speedo gear
wasn't changed when the new wheel and tire size were mounted, so the
actual mileage may be off from that, as well.

Also, can you get a true reading of MPG when you fill up at half a tank?
The reason I ask is it always seems like the first half of the tank is
used more quickly than the second half? Myth, or true?
TIA.

"ravelation" <ravelation@webtv.net> wrote in message
news:19168-3F818147-83@storefull-2336.public.lawson.webtv.net...
> As we didn't mount the wheels, I am guessing the speedo gear
> wasn't changed when the new wheel and tire size were mounted, so the
> actual mileage may be off from that, as well.

Assuming the correct tire size was chosen for these larger rims, the
speedo/odo should not be affected. Althought your gas mileage will be
affected as the larger rims are most likely heavier and have a larger
contact patch (higher rolling resistance).


> Also, can you get a true reading of MPG when you fill up at half a tank?

No. How do you know you're at half a tank? By looking at your fuel gauge?
There's no way you'll get an accurate measurement that way. Fill up with
gas. Drive. Fill up with gas again. Then divide miles driven by gallons
purchased (at second fillup of course).


> The reason I ask is it always seems like the first half of the tank is
> used more quickly than the second half? Myth, or true?

Quite possibly. The fuel gauge is just an estimate at best. It's not 100%
accurate. That's why you cannot calculate gas mileage based on it.

Cheers,

Pete

escape2music@hotmail.com (Pete)
wrote:

>>Also, can you get a true reading of
>>MPG when you fill up at half a tank?

>No. How do you know you're at half a
>tank? By looking at your fuel gauge?
>There's no way you'll get an accurate
>measurement that way. Fill up with gas.
>Drive. Fill up with gas again. Then
>divide miles driven by gallons purchased
>(at second fillup of course).

That's what he's been doing--dividing miles and gallons used. I guess
the point I'm driving at is if you drive more miles on the tank, does it
give a higher MPG than if you fill up often? IOW, will a longer useage
period with more miles and gallons used create a better average?
Is it possible the full tank of gas creates more drag at the first half
of the fill up because of the added weight?

The average weight of the car will be less if you drive longer between
fill-ups. This will, as you suggest, lower your gas mileage, but I doubt
you can measure your fuel consumption accurately enough to catch this.
What I have found to be the biggest source of inaccuracies is that the
point at which the pump at the gas station shuts of varies wildly from
pump to pump. After noticing this, I always fill up at the same pump
every time (if at all possible). This gives me very consistent numbers.

ravelation wrote:
>
>
> escape2music@hotmail.com (Pete)
> wrote:
>
> >>Also, can you get a true reading of
> >>MPG when you fill up at half a tank?
>
> >No. How do you know you're at half a
> >tank? By looking at your fuel gauge?
> >There's no way you'll get an accurate
> >measurement that way. Fill up with gas.
> >Drive. Fill up with gas again. Then
> >divide miles driven by gallons purchased
> >(at second fillup of course).
>
> That's what he's been doing--dividing miles and gallons used. I guess
> the point I'm driving at is if you drive more miles on the tank, does it
> give a higher MPG than if you fill up often? IOW, will a longer useage
> period with more miles and gallons used create a better average?
> Is it possible the full tank of gas creates more drag at the first half
> of the fill up because of the added weight?

My '94 Civic Si has gotten 30.7 MPG over the past 12 months. This is
with virtually no highway driving.

ravelation wrote:
>
> What are you getting around town in your Civic? What's considered
> "normal" for gas mileage? My son says he's getting around 17-18 mpg with
> a/c use and 17's mounted as wheels, and a fart bomb exhaust ('99 Civic
> EX coupe). As we didn't mount the wheels, I am guessing the speedo gear
> wasn't changed when the new wheel and tire size were mounted, so the
> actual mileage may be off from that, as well.
>
> Also, can you get a true reading of MPG when you fill up at half a tank?
> The reason I ask is it always seems like the first half of the tank is
> used more quickly than the second half? Myth, or true?
> TIA.

"ravelation" <ravelation@webtv.net> wrote in message
news:19168-3F818147-83@storefull-2336.public.lawson.webtv.net...
| What are you getting around town in your Civic? What's considered
| "normal" for gas mileage? My son says he's getting around 17-18 mpg with
| a/c use and 17's mounted as wheels, and a fart bomb exhaust ('99 Civic
| EX coupe). As we didn't mount the wheels, I am guessing the speedo gear
| wasn't changed when the new wheel and tire size were mounted, so the
| actual mileage may be off from that, as well.
|
| Also, can you get a true reading of MPG when you fill up at half a tank?
| The reason I ask is it always seems like the first half of the tank is
| used more quickly than the second half? Myth, or true?
| TIA.
Make sure the parking brake isn't dragging or other similar easy fix
(tune-up, etc.). Also, those 17" boat anchors don't help mpg (or handling
or acceleration). The loud exhaust might encourage more aggressive driving
hurting mpg.

: What are you getting around town in your Civic? What's considered
: "normal" for gas mileage? My son says he's getting around 17-18 mpg with
: a/c use and 17's mounted as wheels, and a fart bomb exhaust ('99 Civic
: EX coupe). As we didn't mount the wheels, I am guessing the speedo gear
: wasn't changed when the new wheel and tire size were mounted, so the
: actual mileage may be off from that, as well.
:
: Also, can you get a true reading of MPG when you fill up at half a tank?
: The reason I ask is it always seems like the first half of the tank is
: used more quickly than the second half? Myth, or true?
: TIA.
:

95 DX 1.5L w/automatic and we consistently get 28-29mpg avg, mostly city
street driving (commute doesn't need to include freeway <grin>. However, a
recent run up to LA county (from SD) returned 32.5 mpg. And I attribute this
'low' number to returning Sun early a.m. at speeds averaging 80-85 mph. Only
mod I have are 195/65r15 tires that replaced the 13" that came stock...

As to the first half tank going 'faster' than the second half... My school
of thought is an either/or situation. Either I'm feeling "Honda + gas
economy + full tank = Heavier foot driving" I'm more apt to 'open 'er up'
(ergo waste gas) vs 'Oh shit, I'm getting low on gas = driving more
efficiently' Or, The tanks are designed in a pyramidical (made that word up)
fashion and the sending unit only measures the vertical drop as gas is
consumed, ergo the bottom of the tank has more volume than the top half...
One would hope that the designers would take this into account...

My guess if you were only getting 17-18 mpg around town, somebody's driving
that car pretty hard ;-) Or have your friendly mechanic take a look at it.

Rick

"ravelation" <ravelation@webtv.net> wrote in message
news:19168-3F818147-83@storefull-2336.public.lawson.webtv.net...

>
> Also, can you get a true reading of MPG when you fill up at half a tank?
> The reason I ask is it always seems like the first half of the tank is
> used more quickly than the second half? Myth, or true?
> TIA.
>

I observed the opposite. I figured the top half of the tank is larger than
the bottom, given that the top of the gas is always flat while bottom of the
tank has round edges. Also, if the level sensor is anything like the toilet
float, there's more vertical movement in the first half than the last.

I have a 95 DX 5 speed 1500 SOHC my wife commutes in 90 miles per day at 40-65
MPH, I run Conti touring AS tires 195's on 14 inch rims. The only real mods are
a low restriction air filter and the resonator is removed from the exhaust, the
car has 155k, only 50 k on the motor.. We get 38-43 MPG strictly commuting,
30-35 mixed driving. I've seen the kids driving the finned fart bomb civics, I
suspect the kid has a heavy foot. (hopefully he pays for his own gas!)
BTW we check the gas milage by toping off and driving down to about a quarter
than toping off and taking the number of gallons consumed and devide the miles.
We always use the same gas station.....

rec.bicycles.marketplace

pray4surf@nospams.net (pray4surf) wrote:

>My guess if you were only getting 17-18
>mpg around town, somebody's driving
>that car pretty hard ;-) Or have your
>friendly mechanic take a look at it.

When we bought the car, we had major tune upage done. The fact the boy
is 16-l/2....ding ding ding! We have the answer! (the fact he can
now drive 200 lb. friends won't help his bottom line either!)