could we estimate the gains expected from mods
 

hi

it seems to me there are loads of great mods on this site that we can do that will increase FE. they are listed on different stickys in the sections. however we have no idea what kind of gains to expect from these mods and so we cant plan ahead effectively.

could we estimate the gains expected from mods and list them next to the mods in the sticky threads? i know all cars are different but something must be possible?

If I were to estimate all my Metro mods, it would probable equal out to 1-3 MPG increase on each item I did. Tire inflation would be a definate 3 MPG (or better) increase where the antenna reloction would be more like a 1 MPG increase.

It's really hard to say what the increases are because it takes time to notice them.

If the FE increase for the mods should be based on a percentage of gain. that way you can quantify it.

% from EPA?

There are too many variables to give specific percentage ranges IMO. The ranges of efficiency increase would be all over the place. For example, what good are rear wheel skirts if you are doing all city driving? Do we then qualify each mod with circumstances? 2 mpg @ 60 mph? This is just one example. I think the more we think about it, the more involved it will be.

I think maybe a better way is to generalize it a lot. For example, we have three ratings for a modification; efficiency increase, difficulty, and cost. From there we can rate each of those sections with a general rating of high, medium, low. Something like this would be more possible I think.

Daox, I agree. The same mod on two different cars in the same circumstance could even be all over the map. Generalization is the best you can do. I would recommend a fourth catagory: safety. Many of the suggestions here do increase your risk and need for awareness on the road.

estimate
 

If you can find my installments,they will provide some quanta for which you can estimate.

I saw a definite 2 MPG increase by increasing the tire pressure to 44 psi on both a '97 2.5 liter Subaru and a '96 2.2 liter Subaru, both are 5 spds. I still got more than 70k out of the tires, so I saw no adverse wear characteristics. Hope this helps.

Can we make a sticky somewhere that points to all the A-B-A tests that anyone has done. That way someone can look through that list and link to page where the test was done. So someone looking for a grill block estimate can sort through all the A-B-A tests find the 2-3 "valid" tests come to their own conclusions. It would be a significant amount of work for someone.

No