Ya, my parents are back there, too, and my first wife and my older son.

 

I'm looking forward to it.

 

It's not just a claim, it's a fact. My civic was completely stock for the 3 years I had it until I put on my intake. So pre-mod, at best, it got 30mpg. Then after the mod, it increased to the low 30's. 3 weeks later I put on a new exhaust system, and after watching the miles tick by for every tank of gas, I estimated that the mods boosted my mpg to about 36 for my car and how I drive it. I never mentioned power, but I did get a noticable increase in HP too. Believe me, I wish these nicer features came stock with the civic too. Would've saved me some time and $!

 

I'm not even going to argue to the person who claims 20% increase in fuel efficiency out of simple bolt-ons to already highly efficient engine. Auto makers spend billions of dollars and tens of years on R&D to achive such numbers in reality. You can re-read my self-quote above and think about what part of it refers to you, if you wish.

 

99 EX Manual, Stock with ~45,000 miles - about 36mpg highway.

Same car, with~55,000miles, AEM CAI, and MR Cat-back = 40mpg.

Proven

You will not see insane 20% gains, that's for sure, but every little bit helps.

 

Dude, it's just like Forty said. I'm not claiming an insane amount of gain here. I'm just saying it's true that your mpg improves as you mod on a performance intake and/or exhaust system by stating my own first-hand results in general. Personally, I like being able to say I get the same gas mileage as all the hybrid cars people nowadays are freaking out over, but you don't need to call someone out on being a moron when they are giving you actual test results. I'm being honest, man. And as far as the decisions of the car companies, I can't speak on their behalf, so don't ask me unless you want an opinionated response. Peace.

 

Yes it is true. Hell one guy turbo charged a hybrid prius and managed to get 3 more mpg.

 

Getting about 5-7% fuel improvement out of the turbo sounds just right to the best of my knowledge

 

IHE makers do not care about fuel efficiency. Let me try to explain why I think so. Why do you, or anybody else for this matter, buy IHE? I believe ONLY for the full throttle power gains, be it HP or torque. Why do I believe so? Because I have yet to see a partial throttle dyno chart or a dyno chart showing fuel consumption in any IHE ad or manual. Forget about charts, show me at least a single fuel efficiency number advertised in relation to IHE, I might change my mind then. One has to advertise something in order to be able to sell it, right? Obviously nobody is selling fuel efficiency with IHE, and nobody is buying it.

So, if IHE makers do not sell fuel efficiency, why would they put any money/effort into improving it? They don’t. Those who tried are out of business already or stopped trying. Businesses are run on a slim margin, and expenses that do not translate into revenues do kill businesses on the spot, especially small businesses. If IHE makers didn’t try to improve fuel efficiency, this improvement could happen only accidentally – means it would be rare and in between, if any, and you should not count on it.

Let’s try to see what are the chances of accidentally improving fuel efficiency. Auto makers put literally billions of dollars and corresponding time and effort into R&D to be able to design their engines for the most efficient operation over the widest possible interval of engine speeds and loads, centered around most frequently used engine speed and load numbers. This is what translates into real-life fuel efficiency. And when some automaker manages to squeeze REAL extra 2-3% as a result of several years and many dollars spent on R&D, he is happy to advertise this and we are happy to buy. Now, do you think Honda engineers are dumb *** morons and do not know a **** about what they are doing? Do you think they are just too lazy to consider and test CAI, headers, and catback among hundreds of other things they are testing everyday? Do you think they never heard of those high-tech things in this retarded Japan? Do you think they and their managers just do not care about fuel efficiency? Fine. Then please give me an example of just one mass production car from any automaker worldwide, which uses things like CAI and catback to improve fuel efficiency. Can’t? Me neither. Is the whole auto industry staffed with uneducated idiots? I can hardly believe this. This tells me that chances of measurable fuel efficiency improvement from IHE are not just slim, they are non-existent.

By now I hope I was able to convince you that even if you do not understand why IHE things do not deliver fuel efficiency improvement, there is a serious reason for them to fail on this.

To Kedawei and others who want to understand this reason – sorry, I did not compile the post on this yet. It appeared to be much harder than I expected, because I really did not touch the subject in depth for about 15 years already, and now I have to recall this in the minute detail, and to decide which details are relevant to the topic and which are not, and to compile those details with corresponding logic into something of reasonable length in the foreign language. It’s doable, but it will take some time…

 

I think when you start modding a car gas milage should be your last concern. Like me I could give a rats *** about milage.