Gas went up, cost per mile went down. Yay WAI
 

I did a partial WAI on my car by removing part of the air intake, I have averaged 37 MPG with the WAI and doing the speeds stated in my signature. Gas went up 40 cents overnight, my average MPG went up by 4 MPG.
Now to see if I can hit 45 MPG.

Great move even without the timing on the price increase!

Im still a bit confused on how the warm air benefits the mpg....shouldnt it hurt overall? Cold air is more dense, of course and produces more hp, seems like you would gear down less with more hp...

Seems like my 88' HF has the worlds easiest wai to assemble...just metal flex pipe it to the exaust shield and your done, but how does it work for mpg?

Warmer air fools the computer to open throttle valve more, cause less Oxygen in warm air.
Throttle valve is biggest restriction on a normal gas engine. Less restriction => less loss => better FE

This car has a throttle cable, so the computer reduces the amount of fuel to keep the fuel air ratio correct, other than that you are right.
There is also the perk that the engine warms up easier with WAI.

As for lack of power, downshifting is good in the sense that it means that the engine isn't too powerful, a big engine will use more fuel for a low power output compared to a weaker engine. My car's gearing is so low that I can take a 7% grade in 5th gear, as such more power would just make my FE worse. Your 1st gear is about as tall as my third gear is, your third is as tall as my top gear.
You have a civic that would be ripe for this mod: http://www.aerocivic.com/

I finally read the aerocivic, work has been killing my schedule. He's def got some goals for me to shoot for, if I ever get time lol.
I already replaced the timing belt, water pump and tensioner then work interviened. I gotta do the brakes next, and have a radiator on order...on and on.
No maintenance was done on the car by previous owner obviously... but its the original HF drivetrain and I scored it for cheap, so I can live with it...best of all, 80's tech is easy, and this car is simple by design.
After all necessary repairs, the WAI will be first after getting initial mpg test done on my 36 mile drive to work....if I ever get to work on the dang thing..lol

WAI works wonders on engines that struggle to make heat.

Interesting... I have a Cruze Eco with a 1.4T engine that takes FOREVER to warm up when it's cold, and it gets cold here in Ottawa. I wonder what kind of gains this could provide in warm up times?

I'm planning a full block heater install, so that should do it for the most part, but are the potential mileage gains worth the effort beyond that?

What is the theory behind the WAI increasing mileage? Is it simply that an engine pulls more manifold vacuum for a given torque output at lower intake air temperatures? My car is turbocharged, so I'm not sure if a WAI would do anything... any heat gained at the intake might just get lost through the intercooler.

Someone with a scanguage saw 14 MPG on a cold 4 cylinder engine. I can't remember where.

As far as losing the heat through intercooler, depends on where the flow sensor is...if the sensor was on the intake side of the intercooler, you would still fool the computer but not lose the hp..just a thought.
Or you could bypass the intercooler with a straight pipe...Compressing the air is gonna heat it enough to not even need the WAI...