View Single Post
Old 04-15-2012, 12:44 PM   #135 (permalink)
steffen707
Master EcoModder
 
Join Date: Oct 2009
Location: Midwest
Posts: 337
Thanks: 4
Thanked 37 Times in 21 Posts
Quote:
Originally Posted by Christ View Post
Even at $200, that's 50g fuel, so if I get 3% better fuel economy than my current 53mpg, that's brings me up to 54.5mpg.

53mpg * 50 = 2650
54.5 *50 = 2725, an extra 75 miles per tank.

75/50=1.5 gallons saved per tank based on previous mpg
50*1.5=33.3e tanks before I start saving from the mod's benefits.

This is with fuel at $4/gal. It's $4.25 or higher for me, so payback time is less.


Realistically, most p people only use 75% tank capacity between fills. Scale the figures accordingly.
I think your math is off. Consider this
10,000miles / 53mpg=188.6 gallons to travel 10,000 miles
10,000miles / 54.5mpg=183.48 gallons to travel 10,000 miles

saving you 5.12 gallons per 10,000 miles or $20.48 saved per 10,000 miles
$200 could have bought 50 gallons of gas / 5.12 = 9.76 multiplier

so in 97,600 miles this mod will pay for itself. From a strictly financial standpoint for most people a break-even point of 97,600 miles from now is a horrible return on investment. Imagine all the scenarios that could happen that make you sell the car, job, kids, car accident, ect. That's a long way into the future for most.

Although that's just a financial standpoint, there's external benefits from earth friendly, personal happiness, braggin, being a tinkerer, ect.
  Reply With Quote