Thoughts on fuel economy

[Oldiron440]

Happiness is being able to watch your fuel gauge drop a quarter tank in ten miles!

 

[273]

I beg to differ.
If yur only targeting a couple of mpg, ok sure, I get you.
But why settle for sub-20s mpg, when it only takes overdrive to pump it up to, in my case, over 30, in point to point cruising. My GVod paid for itself post haste, and my engine has saved 28% wear over the first 100,000 miles that it has been idling down the road.
Cutting my fuel bill in about half, means I can drive to more places and further away, with the money that I saved. Plus it paid for my alloy heads real quick.
2mpgs is chicken feed. Aim higher.

My point if it’s purely to save money not enough seem to think of calculating the cost benefit of any mpg mod.

A lot of these cars are play toys that don’t get driven much, So depends on how long you’re likely to own your car, how many miles you’ll put on and what mpg you’ll gain and the cost for doing so. Bet a lot of the time it doesn’t work out so well.

 

[j par]

Fuel mileage ??.... lol...

 

[273]

Eg.. Look at going from my 5.9l jeep 12.5 average mpg to my Avenger 21 mpg, probably saved about a $1000 a year and paid $7,500 plus interest so it took 8+ years just to break even, that’s with an 9 mpg increase.

 

[mbaird]

We do all kind of stuff to our street driven Mopars to get another 40 hp that we won’t use on the street just because we can. . Why not try to optimize fuel economy? Its just another way to tinker .

 

[273]

We do all kind of stuff to our street driven Mopars to get another 40 hp that we won’t use on the street just because we can. . Why not try to optimize fuel economy? Its just another way to tinker .

That fine, no one is saying you can’t, my point is if you want to save money especially in a short timeframe, if it takes 5, 10+ years to recoup your investment your definitely not save anything in the short term or at all depending on the situation.

 

[mbaird]

I am putting a magnum in my 71 Dart, not sure if 318 or 360. It will have the complete fuel inj and 46re, dana 60 with 3.54 gears. I have changed the cam in the 360 to the 318 cam as it has more lift and duration, per the fsm. I will be using a 360 pcm. Any thoughts on the difference in fuel economy between the 2 engines? If only 1-2 mpg, I will use the 360. If 5 or more difference, I will use the 318. I know it may be a loaded question, but this will only be a cruiser. Tires size will be 275-295, if I can fit them under after moving springs inboard. thoughts are always appreciated. rick.

If you’re looking for mpg ditch the 275-295 tires and go with a 225-255. 275-295 is way more tire than that combo could turn (burn) and the extra weight/drag eats a lot of fuel .
Will they even fit under your Dart ? My 69 Swinger has 255/60-15 Drag radials and they barely fit .

 

[Oldiron440]

How you drive has more to do with mpg than the tinkering you do with your car. That old saying drive like you have an egg between your foot and the gas pedal can pay off.

 

[Jim Lusk]

How you drive has more to do with mpg than the tinkering you do with your car. That old saying drive like you have an egg between your foot and the gas pedal can pay off.

That works for the old carbureted stuff, BUT I have found that with modern (OBDII stuff) getting up to speed relatively quickly without flooring it gives better mileage in the cars that I have owned.