Freaky Math Fun

Thread starter #1

Capt Quirk

Senior Member
For this post, you will need either a #2 pencil and piece of paper, or a calculator.

Your back, so let's get started! I just got a new truck a little while ago, it's an old 1970 F100. Due to it's age, it has some wear, and lots of time for ambitious folks with questionable mechanical skills/sense. One issue, is the fuel gauge only works part-time. After running out of gas a few times, I now keep a full can of gas, and check the mileage whenever I park.

This is where the math comes in-

I filled the tank at 37,581 miles. Yes, it would be fair to assume it isn't the first time it has seen 37k. I go to Wally world, and the fuel guage is working this trip. When I park, the mileage is 37,641, and the guage reads half full... Or half empty, depending on your own beliefs and outlook. But this is math, not philosophy.

Anyways, the tank holds 18 gallons. So, for the slower, or drunker, out there we have 37,641 minus 37,581, divided by 9 gallons.

I don't know which I should worry most about :unsure:
 

Batjack

member #1313
A little better than my 2000 van gets. 142 miles to my Brother's house, 30 gal. take, fill up before leaving...need to fill up once there.
 
I would say you can't trust that gauge to give you a true reading at any time
 
Running without a working gas gauge will bite you someday worse than the rust that caused it.

Fix it. Now later next month.
But fix it before it bites again.
 
You are okay as long as the gas can on the back of the truck is full. If you have to use the gas on the back, as soon as you get to another station, fill the truck and the can both up.
 
Thread starter #11
The truck in question, had a big 400 stuffed in it, and a big 4 barrel Holley carb. Somebody decided to make a race truck out of a respectable farm truck. You know, big motor, loud pipes, mag wheels, and then rig stuff and twist what wires you don't just hack off.

I'm in the process of tuning the carb in, but had to replace the fuel pump. Twice. It's hard to tune carbs, if it won't idle. There is a long list, it is a work in progress.

My main point, for those who didn't get the math, 37,641-37,581=60÷9=6.66 .
 

Crakajak

Daily Driveler News Team
Only way to make sure of you milage calculation is to run it out of gas...add 5 gallons and run it out of gas again.....measure the mileage and then you will know your mpg....because I am old,grumpy,slow and a retired drunk.:ROFLMAO:
 
we use to hook up a gallon gas can with a flex hose to the fuel pump, after disconnecting the line going to the fuel pump. You will know to the second just how far a gallon will take you.
 
I am no help.

I got in the middle of the same math problem when I was sneaking my dad's old car out for joy rides/drives when I was 13.

It didn't end well for either of us.

I can still smell smoking belt leather from that beating!
 

GoldDot40

Senior Member
The truck in question, had a big 400 stuffed in it, and a big 4 barrel Holley carb. Somebody decided to make a race truck out of a respectable farm truck. You know, big motor, loud pipes, mag wheels, and then rig stuff and twist what wires you don't just hack off.

I'm in the process of tuning the carb in, but had to replace the fuel pump. Twice. It's hard to tune carbs, if it won't idle. There is a long list, it is a work in progress.

My main point, for those who didn't get the math, 37,641-37,581=60÷9=6.66 .
6.66 mpg sounds about right for what it is.

On the tuning, make sure you have the timing spot-on before you even waste another minute on the carburetor. A lot of people will attempt to "fix" idling/starting issues at the carb when it COULD be a little out of time. A timing light is always your friend...then go from there.

Holley carbs are easy once you get to know your way around them. Biggest downfall to them are that they are very sensitive to the tiniest piece of trash. Don't skimp on a GOOD gas filter...or filterS.
 
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