As part of my daily update on Oldsmobile collectibles from ebay, this popped up today, and it got my attention. Probably not the most accurate, but a cool piece nonetheless.
Fuel mileage calculator

 

The flaw with fuel mileage accuracy has always been knowing exactly how much fuel you used. It's very difficult to repeatedly fill the tank to exactly the same level. This is why actual mileage tests use specially calibrated tanks. Add to this the inaccuracy in your odometer and you are compounding the problem. Both of those will swamp any accuracy issues in this calculator. Personally I just use division.

Actually, I lied. Personally I just don't ask the question that I don't want to know the answer to.

 

I think that is a cool swag item.

 

‘There is the correct answer. Nobody’s gonna quit driving these cars if you love them like we love them because they don’t get the fuel mileage thought they should get lol..😆

 

when I top off my tank to check fuel used , I always go back to the same station and same pump. fill till it clicks off, wait, let the fuel settle….then fill till it clicks off again.
it’s very simple…as long as you do the initial fill and refill the same way, it’s accurate

where are you having difficulty?

 

even if you don’t top off the exact same way..the MPG difference between topping off the same way or a tiny bit short is minuscule…it dont matter when you’re dealing with 15 or 20 gallons.

just make sure it’s near the max tank capacity

 

I thought about that piece for my collection. It is sure rare to find that, only one I have seen. I have a pretty large collection of Oldsmobile, REO, Fisher body (Lansing) and Motor Wheel. I never counted but a solid guess around 500 items. Short list of rare items Olds ave street sign, Oldsmobile serving tray, Golf shoe bags, Oldsmobile security jacket and 35 year Oldsmobile service ring.

Pat

 

I bought one of these many years ago, to add to my collection in the Olds curio. Had no intention of ever using it. It's a great item and it's not a space hog.

 

My '23 Chevy truck and my '24 Buick Encore both give me, as part of the million things that the dash will tell you if you push the right buttons, both the instantaneous and average fuel mileages. It's interesting, for example, to see the difference towing the trailer with a car on it makes. Drops the average mileage from the unfettered 21-22 mpg down to about 16 to 17.

Yes, yes, yes, now everybody jump on me and tell me how inaccurate the computers on modern cars can be and how older cars were always better and blah blah blah blah blah. There, I just saved you the trouble.

 

On a more serious note, no, you can't always fill to the exact same level. So tank to tank, your calculated fuel mileage will vary. But you can greatly solve this problem by simply making the calculation over time. Fill the tank and note the mileage. Next time you fill the tank, note the mileage and fuel used, and calculate mpg. Do this ten times in a row, average the calculated mpgs, and the value you get is probably a pretty good measure of the actual mpg your car is getting.

 

Except then you have variability of how you drove, temperature, traffic, etc, etc. Yeah, sure, the difference is maybe 10%. Like I said, I don't ask the question I don't want to know the answer to.

 

Yes, but this is why you make the calculation over 10 or a dozen fill-ups. And you don't need to know the mileage down to the third decimal point. To the ones place (20 or 21 or 19 as opposed to 15.556 or 20.257 or 21.348) is plenty good enough.

 

Great find, I have one from my Oldsmobile dealership days. I believe these were service giveaways in the mid to late seventies.

 

there's another on on Ebay right now, albeit not as nice as the one that sold a couple of days back.

https://www.ebay.com/itm/23670977624...Bk9SR6aP4de_Zw

 

I bought the one that sold a couple days back

 

That is a neat item to add to the collection. Odd the way this post went from showing a neat little Olds related trinket to a full blown argument about the accuracy of calculating fuel mileage.

 

LOL...yup...down the rabbit hole it went...

 

Out of all the items in my curio at that time, this was the one item that grabbed the attention of others the most.

 

Last year I took my 65 Starfire on the Power Tour. The drive was 4956 miles. I kept all my receipts for gas. My average was about 10.4 miles per gallon for all driving. That surprises me how many miles I was getting per gallon.
Now my 32 Ford three window coupe with a 350 Chevy and dual quads is a completely different story. It gets less than 8 miles to a gallon no matter what mood my foot is in!
HAPPY MOTORING!

 

I view mileage as a performance health metric. It doesn't matter if my car gets 12.2 doing 60 or so, it matters that it should be about there as that is typical performance. Similar to I don't care exactly what degree 40% of my temp gauge is, but I do care that the needle is about there to be showing typical performance.

 

whats preventing you from filling to the same level? the same pump clicking off at the same time while holding the nozzle into the thank the same….if you can’t figure that out..you shouldn’t be driving