Method to madness (Fuel Economy Testing)?
 

So, I've begun planning my modifications... What's got me stumped is how in the world, around the "Mile High City", I'm going to perform my testing. Between Wind/Weather/Temp, Traffic, hills & FRAKING MOUNTAINS... I know I need "apples" to "apples" tests, so Idealy I don't want to break my tests up over inconsitant periods of time.

so.... I'm Wondering...

Should I plot a simple "Repeatable" path? (instinct tells me yes)
How long should should the drive be? Approximate 1 Gal usage (i.e. Approx 30 miles), 2 Gal (60 miles)?
I'd think that for the best apples-apples comparison, I should attempt to fill up at the same station?

I know in the "scientific" world they have pre-metered fuel, measure distance and how long it takes to go through said amount of fuel... (or how much is remaining and figure out usage divided by distance)... I don't have that kind of luxury

Carbureted (so mpguino won't work)?

If so, where is the fuel pump located?

If you don't want to burn lots of gasoline just testing, I'm thinking a manually switched aux fuel tank - like a full sized pickup or suv with dual tanks - only a super tiny 2nd tank (1-2 quarts). Even at only $2/gal it won't take many test runs to pay for itself.

I do my testing using my fairly long (50 miles one-way) balanced (one-third urban, one-third rural roads, one-third Interstate) circuit for real-world MPG testing.

Since I don't have precision fuel metering equipment, I use long tests and all the inaccuracies average out.

As A result I think a valid MPG testinvolves about 1500 miles. Four fill-ups.

ScanGuage is OK for short-term comparative tests, but snapshots are NOT real world MPG

Mechanical CIS fuel injection... the fuel pump runs a super high PSI (75psi minimum), a minimum flowrate of 85L/hour, plus if it runs out of gas flowing through they tend to burn up ($185 new).... not to mention a significant air-bubble in the CIS system can lead to all kinds of issues.
There is no actual "ECU", only an Emissions Control Unit to fine-tune adjust the mixture.... saddly to Stoich (I've got my work cut out for me to hit my goals of 35/40 MPG)... so Scan Gauges and the like are no-bueno

hmmm... good point on the "mix", I think I can pull off a good 50/50 of Highway/City

Southcross, Just to get the context... What makes you persist with this old ghost of a vehicle?

:rolleyes:
becha I spend less on maintenance in a year than what you pay for insurance and bank note in a month ;)

Bravo. I averaged under $200 per year for parts and depreciation on old Toyotas for a decade. I think my cars are appreciating now, but it is taking more work. Considering what generating money does to the planet, no expense is unimportant - the fuel bill is just the hardest one to work on. Replacing a car makes a lot of factory smoke.

don't get me wrong.... if your going to buy a new car, get the most efficient one for your buck... but if your going to replace a carjust for the economy, it reminds me of the saying "The Prius is an Economy car for people who can't do math". A $300/month car payment + Insurance for 30% better gas mileage that what I'm getting right now.... I would have to drive 6,500 MORE miles per month to "save" money :thumbup: