Gas milage..?

[Peer]

Usually I drive with the top down, even when it's cold, but for the heck of it I decided to check my gas-milage with the top up. (Well, this was actually the first time I checked the gas-milage) And yes, mine is a none-opt model.

After depleting one tank of gas on 70% freeway, 20% city, and 10% high-rev canyon roads, I ended up with 23.4 MPG.

Is this about average for a '98 Box with its top up?

-- peer

[CJ_Boxster]

Well, i filled my tank to the brim and i drove about 120-135 miles before using half a tank of gas, So i would be getting anywhere from 240-270 miles per tank full...... topup the entire period. whats that equate to in mileage per gallon?

Edited January 2, 2007 by CJ_Boxster

[bcc]

Usually I drive with the top down, even when it's cold, but for the heck of it I decided to check my gas-milage with the top up. (Well, this was actually the first time I checked the gas-milage) And yes, mine is a none-opt model.

After depleting one tank of gas on 70% freeway, 20% city, and 10% high-rev canyon roads, I ended up with 23.4 MPG.

Is this about average for a '98 Box with its top up?

-- peer

I drive 80% suburb and 20% freeway with a 98 boxter and according to the onboard computer (I didn't redo the computation myself) I do 24.3 mpg with the top down as often as I can.

When driving on a 5 day trip in the smokeys (blue ridge parkway mostly so not too quick but a bout on the tail of the dragon) with a drive to and from Charlotte (4 hours freeway) the first and last day I got 26 MPG, that was also with the top down as much as possible including on the freeway.

Your number seem a bit on the low side.

Benoit

[bcc]

Well, i filled my tank to the brim and i drove about 120-135 miles before using half a tank of gas, So i would be getting anywhere from 240-270 miles per tank full...... topup the entire period. whats that equate to in mileage per gallon?

A good way to know your mileage is the following:

1) fill your tank

2) reset your trip odometer (or note your mileage)

3) drive

4) when it is time to refill, fill your tank completely and note the number of gallons

5) divides how much you drove in 3) by how much you filled in 4)

I am afraid that "half tank" or "full tank" are not very good measures as they are never really half or full tanks as you never know what is left in your tank

Benoit

[Peer]

bcc wrote:

> A good way to know your mileage is the following:

> 1) fill your tank

> 2) reset your trip odometer (or note your mileage)

> 3) drive

> 4) when it is time to refill, fill your tank completely and note the number of gallons

> 5) divides how much you drove in 3) by how much you filled in 4)

A good way..? I didn't think there was any other way...

-- peer

[rsfeller]

This winter I'm getting 325 miles out of a tank with 90% freeway drive, top up and mid octane gas. I had two tanks of 350 over the holiday with long runs to family at moderate speeds...

on average I'm doing 300 miles before the light comes on with 70 highway 30 city with lots of high rpm sprints for fun...

Shawn

Ohio

PS my main car is in the shop so I'm driving my 986 7 days a week (100 miles per day) to work for the last month, ouch!!

[bcc]

bcc wrote:

> A good way to know your mileage is the following:

> 1) fill your tank

> 2) reset your trip odometer (or note your mileage)

> 3) drive

> 4) when it is time to refill, fill your tank completely and note the number of gallons

> 5) divides how much you drove in 3) by how much you filled in 4)

A good way..? I didn't think there was any other way...

-- peer

Well that was a reaction to another post which I quoted, I was trying to point out that

the info CJ_boxster gives are not sufficient to compute the MPG value.

About another way though, the onboard computer on my boxster has a function that gives the MPG average since the last reinitialization.

That is what I usually use. I don't know how accurate it would be but probably same as the above method. Talking about that, the real problem about the way to measure that I described is the odometer reading, I noticed that my speedo is always showing a higher speed than what I am running at according to my GPS and I wonder if this reflects into a higher number of miles on the odometer. I have been wondering about that for some times actually as the difference is significant (maybe 8%) and car prices depends on the number of miles. I am really not an expert but I assume that odometer and speedometer both rely on the number of turns from the wheel and they could both be off if the assumed wheel perimeter is incorrect.

Benoit