mileage readings

Every now and then I'll be too aggressive filling the car to get every last drop in, especially on long trips but lately I don't worry much about it and stop filling it at a safe level. An extra 10 oz in the tank doesn't compensate for a spill.  I get it close to the top and stop. 

All my MPG figures are a little different even driving the same kind of roads at the same speed so I just average the MPG numbers for several tankfulls and let it go at that.

I have  adiffeent situation than Carl though---he is still experimenting and I am pretty much finished tweaking my tires, jets, etc, etc.  I just drive it now!   Lots.

Carl, I run it down to around 1/4 tank and then add 5 gallons and average it out over 2 or 3 zillion km. Close enough for me and I'm usually ready to get out and unkink anyway.  Your car runs fine and looks great ! Stop worrying about that stuff.  (and don't forget the AAA gold)

Tom,

A year n' half ago when I first parked this VS in my driveway I realized that despite previously owning a '59coupe and a '61roadster that I had a steep, daunting, learning curve ahead of me...and as Jack commented "I'm still experimenting"

Anticipating potential problems or diagnosing existing ones was (is) nerve wracking. The more I understand, the more comfortable I sleep at night.

Al, you make me smile. 

With that AAA gold card in my pocket I don't have to medicate myself now when venturing beyond the city limits!!!!! 

If you're really that concerned about mileage then do what some race teams do.  Go to Home Depot and buy a wood dowel rod about 3/8" in diameter.    Empty your gas tank then start adding fuel in measured amounts.  Stick the tank and with a pocket knive, notch the dowel and record the quantity.  Later, after the gasoline has dried on the wood dowel, you can use a wood burner or soldering iron to permanently mark the lines and quantity.

It's a lot of initial work but again, if it's a "must know" then this will work.

Larry --I always did exactly that with my airplanes.  Then I would correlate the actual fuel in the tanks with what my fuel gauges read.  Mighty nice to know the truth.

Jack,  

It's always nice NOT to run out of gas in an airplane..

Speaking of airplanes, the similarity between a parachute and a gun:    If you need either of them and don't have them, chances are you'll never need them again.

This...  

""This"" WHAT?????

What?

Honestly, now......I have never paid a whole lot of attention to what Pearl gets for gas mileage.  It's somewhere in the upper 20's, but that's about as close as I get.  After all, even with high-test (which ain't so "high test", anymore), at six gallons and $24 to fill it once a month or so, I'm not gonna get too awful excited about it.  

What's WAY more important is how much is left in there when the gauge needle hovers around zero (or in my case, the big "R").  At that point, I have about a gallon left, or about 20 miles with a cushion (however small that cushion might be) so when it's kissing "R" it means, at least on my car; "Hey.....Dumb Ass!  You should Really fill me, and NOW!"

I am with several....  Close enough is fine for me....

I reset my trip and can get about 140 to 7 gallons around town unless I am hot rodding it.  Highway, about 180 and I had better have a gas station close because if I hit 200 I am on borrowed time.

It seems my question on mileage readings has been misinterpreted.

I'm only vaguely interested in gas mileage.

But I'm very interested in the possible difference in gas mileage between spark plugs and jetting combinations,... between mechanical and electric fuel pumps... between BTDC of my 09 dist. and the fuel burning difference at the BTDC setting of my soon to be installed 050 dist...between my present Yokohama 185's, and the Michelin 175's I have waiting in the wings.

This intent of these comparisons isn't a maniacal quest squeeze the best possible MPG out of my 2110...it's simply to know if there is any difference!!! 

For this information I need accurate fuel consumption data...which will require a very precise, repeatable, tank filling proceedure.  

That seems like a whole lot of thinking to know you will be + or - 1to2 mpg.

In the 8 gallons of gas, that is not that much difference in mileage. + or - 8to16......

good luck.

If you really want that type of measurement, get a flow meter and install it in the line between the fuel pump and the carb(s). I'm assuming you do not have a return-style fuel layout. You could start with something basic like: http://www.boatersland.com/farffm027.html But of course, how accurate you want to be depends on how much you want to spend.

You'll never get repeatable results just relying on a tank reading. Simple traffic changes just on the way to the gas station could easily mask the differences you are trying to see.

Thanks Justin for the heads up. But my curiosity doesn't warrant purchasing a flow meter.

And you're absolutely correct in the difficulty of arriving at repeatable results...but over time, once I perfect a reliable fuel tank filling technique, the accumulated data will smooth out inconsistentcies and a trend will become evident IF there are fuel efficient combinations...To what degree is immaterial...I just want to know what they might be. 

To get valid results that way, you'd need to keep your driving as consistent and repeatable as possible over the entire duration of all your tests. Do you really want to spend all that time concentrating on your driving habits instead of enjoying the car?

Justin,

I won't be concentrating on 'consistentcy'. Being a creature of habit, my driving - where I go and how I go - is very similar from tank full to tank full. All I'll have to do is keep an accurate record of each fill up (mileage & fuel, under component that's being tested) and then go on my merry way!

When I eventually install the EJ22 I'll 'crunch' the data in that notebook to see if there were any variations in the feeding and care of my 2110...Results will be interesting one way or the other. 

For what its worth.....   I have always kept a log in my truck in which I log all my gas purchases.....   Quantity, price per gal, milage between fillups, and miles per gallon....

This has helped me spot some approaching problems in the past as well as teaching me how to stretch the mpg....  I had an '85 Toyota long bed 5 speed that averaged 27.5mpg +/- even  though it was flogged mercilessly from day of purchase....  My Nissan only averasged 25.7mpg....  Both of these trucks went in excess of 200,000mi.   The current Toyota 4 cyl. 2.7L. is getting about 27.5 on the open road and 25 "in town"....  It helps...  

has anyone found a decent app for the the iPhone that they use to track fill-ups and mileage?

Tom,

An infallible, tamper proof fail safe and inexpensive 'ap' consists of a pencil and small notebook. 

paper and pencil I have...but looking to upgrade 

Carl, you just make me smile too .

If you want to upgrade from paper and pencil,  try a fountain pen and parchment??

Go old school - a clay tablet and a sharpened stick.  Hey, it was good enough for the Phoenicians.

Who you callin' a Phoneician?????  I might resemble that remark....