syzygy

So I tried running down my "approximate range" to literally 1 mile left before I filled up gas, and I filled up 14.699 (~=14.7) gallons of gas.

The fuel tank capacity for this car is rated at 17.2 gallons. Had I let it run down to "0 mi," would something special have happened indicating that I (theoretically) should have 2.5 gallons of gas (50 miles) left?

Edit: Car is IS350, if it matters.

DLam

iTrader: (4)

no nothing special would happen. the longest ive went on "0miles" is about 25miles then i got scared so i filled up lol

XhyDra

iTrader: (8)

Yes sir. I've tested this to an extent to see how many miles mark up the reserve tank. So far at 30 miles past 0 I'm 16.100gal in use. I would say getting any closer could cause the pump to choke or be deprived if you make a turn hard enough to toss the gas around the tank.

L-S-D

iTrader: (-1)

Good to know lol

jackblack7

I think it's more like 2 gallons. I regularly fill up at 0 and typically put a little more than 15 gallons in.

Lexus@17

iTrader: (3)

wow good to know!
i went to 1mile one time and i was soo scared lol

edgeucated

iTrader: (4)

i havent tested this yet cuz im too scared to get air inside my fuel injectors

syzygy

Interesting to see the effects of going WOT on mileage. The range calculator started out at 9 mi left. I went WOT from 0 to merge onto a 65 MPH highway, and it immediately went to 6 mi within the span of a quarter mile.

I will say though, there is a noticeable difference in acceleration when you're running on a virtually empty tank versus running on even half a tank (and certainly full tank).

Gasoline weights roughly 6.5 pounds per gallon, our capacity is 17.2 gallons. If you shed 15 gallons of gas (i.e. you'd be around 0 mi left for the range), you've just lost 15*6.5 = 100 lbs of weight.

Drop more weight by getting rid of your spare tire, get some lightweight tires that have minimal rotational inertia, and you start to realize that it's very easy to improve performance in a measurable way via these weight reduction strategies.

100 lbs of lost weight (achievable just by running on low gas) has been proven to shed approximately .1 seconds from a quarter mile run, and you can definitely feel it.

I've ran 13.32 @ 104 MPH at the drag strip with 3/4 tank of gas in my bone stock IS350, and with my spare tire, and with a 60' time of 2.2 seconds

Just imagine, people have shown it's very possible to get 60' times of 1.9x. If nothing else, getting a 1.9x 60' time traction run would at least eliminate 2.2 - 1.9x ~= .2-.3 seconds from my quarter mile time.

Add on the fact that I could shed potentially .1 seconds more by running on just a few gallons of gas (via 100 pounds of weight lost), and more weight reduction by removing my spare tire, and even greater reduction with lighter tires (that have less rotational inertia), the possibilities are very intriguing.

syzygy

Oh quick caveat, the temperature, and more important, density altitude, were highly in my favor during that run. It was less than 40 degrees Fahrenheit outside.

syzygy

Ehh actually looking at my time slip, my 60' time was 2.13 seconds, not 2.2 seconds. there is still .1 to .2 seconds at least for improvement if you consider a 1:1 ratio for 60' time reductions : 1/4 mile time reductions. It's been shown that it's a 1: >1 ratio, usually (some argue it's 1 : 2 but I think that might exaggerating a little bit)

IS250TW

iTrader: (3)

yeah i heard someone wanted to increase the mpg so he always fills up with only half tank of gas just to reduce the weight
and i think that really does something.... but its pretty annoying that you have to go fill the gas all the time

uz07lex

iTrader: (14)

I normally dont take it pass 5 miles only because the fuel also keeps the pump cool.