False, I jumped about 4 mpg with just a CAI and Cat-back

 

You sound a bit flat for an administrator.

Think about it: if it would be as easy as a couple of bolt-ons to boost the mileage more than 10% while getting decent power increase (what you just claimed), why would Honda ignore this in all of its stock models? And in VX model, too? Americans obviously did not care about mileage till recent times, but the rest of the world did care a lot, and continue to care. Can you give any make and model worldwide which uses things like CAI and catback to boost mileage?

Usually, when people claim they get mileage improvement out of such a mods, they either lack facilities/equipment/knowledge/experience to do proper testing; or they did other repairs/maintenance/adjustments at the time of mods installation. If in the former case there is no real measurable improvement, in the later case improvement really exists due to bringing car back to original manufacturer specs.

 

It's really hard to get accurate results unless you have access to a controllable environment, but, those were the numbers that I came up with. Prove me wrong. Like I'd mentioned before, I did the absolute best that I could to make sure that all variables were as close as they could possibly be. However, I can't change the weather, so obviously temperature, humidity, and things of that nature contributed to the results I saw. I ran three tests prior to install, and two after, which was all we had time for that summer.

I never claimed to get a "decent power increase" from those mods either. And of course manufacturers aren't going to put stuff like cai's and 2.5" exhausts on their cars outta the box. IMHO, they're too close minded to do so. There are risks with throwing a CAI on an economy car, such as hydrolock. One car goes through too deep of a puddle, and WHAM,, theres a massive recall on all civics with OEM cai's.

Not to mention, like someone mentioned above, when most people get a CAI they hear that nice loud noise, and start flooring it everywhere they go. This will obviously decrease gas mileage, so why tempt people to drive like this with an outta the box economy car.

 

ya you can do all the improvements ya want..... BUT can you still drive the same.....LMFAO

i upgraded to both cheap intake and header... BUT i also added my system and i drive my civic alot harder now.LMFAO
with the car preaty much stock i got 38mpg highway 75mph on a road trip...
BUT havent done a road trip since the upgrades and addons...
but i typicaly get 27mpg now... and thats with my lead foot since that intake sounds cool.LMFAO


but for improved mpg its mainly your driving habits....
i drive to work every morning going 80-90mph..... and city driving back from work......
if i stuck to 65mph and didnt lead foot it im sure id get alot beter.LMFAO
when i got the car i was geting 33mph with preaty easy driving...

 

I can’t prove you are wrong (or, to be more precise, I can’t point out errors in your methodology) without knowing all the details of how did you perform the measurements and comparison. I can tell you how I would approach such a task, and you can compare for yourself.

If I had unlimited funds, an idealistic approach would be: I would take two identical cars (make, model, year, mileage), two identical fuel measuring systems, two drivers, and one set of I/H/E in question. And then have those drivers driving those cars side by side for a couple of months or so. I would swap drivers, measuring devices, and aftermarket/stock I/H/E every day in different combinations. And at the end average the results. Only this way I could be reasonably sure I took care of both systematic and random errors.

In real vehicle owner’s life such a precision is much harder (if not impossible) to achieve. The best methodology I can think about would be: You pick a gas station as close to your garage (or any other place where you will be swapping parts) as possible. You pick one pump at this gas station, and for the whole period of measurements you fill your tank only from this pump. For a couple of months (better more) you keep swapping stock and aftermarket I/H/E just before or just after you fill the tank (does not matter before or after, but when you pick one you have to stay with your choice). You try to use as much fuel as you can between fills. You always fill until the pump shuts off by itself and you never top the tank. At every fill you write down the number of miles since previous fill, the amount of fuel filled, and reset the odometer. At the end you just do your math – sum up four columns and perform two divisions…

And do not forget to calculate the error. My guesstimate for this method error would be not less than 2-3%, which significantly exceeds any theoretical gain you might be able to get from I/H/E… And this is the best method I was able to come up with.

I’m not going to believe you spent your bucks for nothing. And, I’m not going to believe you spent them purely to better your gas mileage, either.

So you was not able to find a single car that uses I/H/E for economy. Than see my new sig, please. It was for the different matter, but works fine here, too. Come on, there are still some bright minds in the industry. And, btw, I own two relatively modern cars, and both have sort of a CAI out of the box. It’s not shiny and does not have a cool filter hanging at the end, but it takes air from the best possible location – radiator grill, utilizing dynamic air pressure at high speeds, too. And it is not prone to hydrolock.

 

Seriously, read, I bought thatstuff for added throttle response. It also helped get me into turning wrenches on Honda's, as I'd never owned or worked on one before.

Stock intakes like that are restrictive. They have small intake points, tons of bends and are sometimes ribbed on the inside, which are all factors that will result in airflow being less smooth. Swapping that out for a smooth, 2.5" pipe with only one or two bends is anobvoius step in the right direction.

 

As for my testing methods, I told you that they were as close as they could possibly be, without going to any extremes. Same gas station, same trip, same shifting points, same weight in the vehicle, blah blah blah.

My results stand, no matter how impossible you think it is.

 

on my last tank of gas i got roughly 32 mpg and that was with some good 5-10 pulls of the turbo spooling im also semi tuned with safc-2 and some rc 310cc