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post #1 of 13 Old 01-28-2009, 12:23 PM Thread Starter
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Header questions

This is kind of random but I guess from what I've read we don't benefit too much from headers since our stock ones are pretty good...Here's where the question comes in a buddy of mine has a integra n/a and he just got headers and was saying that he would see like 20 or so whp from them is that true? I was always under the impression that 4 cylinders in general don't really gain as much of bolt-ons like v8's do.

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post #2 of 13 Old 01-28-2009, 01:07 PM
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Any time you free up your engine from having to work harder, you'll see gains. The easiest way to do this is to make it flow better on the intake(giving it more air/better flow) or the exhaust side(making it easier to get rid of spent exhaust). The engine has to do less work to get rid of the exhaust with better flowing headers and so the output is increased.

Honda's are different animals. Mostly bolt-ons for them are plug and play. WRX's can definately benifit from a good set of headers, but they need tuned to see the gains.

But 20 at the wheels seems retardedly high...maybe 7 to 10?

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post #3 of 13 Old 01-28-2009, 02:12 PM Thread Starter
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Yeah thats what my theory was as well, thanks for clearing that up, I mean hes got a intake/headers/exhaust so I guess its kinda quick but I didn't think those numbers sounded to right.

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post #4 of 13 Old 01-28-2009, 02:30 PM
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those damn ricers.

they like to believe those advertisements and they (low hp car owners) call it whp, instead of hp at the crank.

jk. lol

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post #5 of 13 Old 01-28-2009, 03:30 PM Thread Starter
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haha nah no need for the jk I agree...I mean I am friends with the guy but hes one of those as I call "bubble civic people" who think that weight is all that matters, and that holes on the rear bumper are cool >_<

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post #6 of 13 Old 02-01-2009, 05:14 PM
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haha nah no need for the jk I agree...I mean I am friends with the guy but hes one of those as I call "bubble civic people" who think that weight is all that matters, and that holes on the rear bumper are cool >_<
EWWWWWWWW lol sometimes i just don't understand the world
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post #7 of 13 Old 02-01-2009, 09:16 PM
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Your friend will be lucky if he even sees a 5hp gain.

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post #8 of 13 Old 02-01-2009, 11:53 PM
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Headers are usually a good way to get low/mid/high increases depending on the motor/type of header on an NA engine.
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post #9 of 13 Old 02-02-2009, 09:58 AM
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This is kind of random but I guess from what I've read we don't benefit too much from headers since our stock ones are pretty good...Here's where the question comes in a buddy of mine has a integra n/a and he just got headers and was saying that he would see like 20 or so whp from them is that true? I was always under the impression that 4 cylinders in general don't really gain as much of bolt-ons like v8's do.
The problem is don't compare N/A engines to turbocharged ones.Yes gains can be had by getting a header but everything has there pros and cons.Equal length headers will provide the best power output.And yes,you can see gains of up to 20whp and 20 ftlbs but they will probably not be "peak" numbers.You will see the biggest gains in the midrange.Turbocharged cars won't really see the scavenging effect like n/a headers due to the turbo canceling that out.

Header FAQ: Read if you are thinking of buying one! - NASIOC
Interested in a stock manifold/ported/ported + crosspipe/equal length header comparo? - NASIOC

As for Honda's being plug and play,not so true.Most Honda's are "speed density" or MAP based fueling.MAP based fueling cannot account for changes in VE like MAF based fueling can(Subaru's).Changes in VE = engine mods.Header,intake,heads,cams...you will see barely any gains without tuning for them due to zero compensation in fueling or timing.MAF based fueling can account for this somewhat,but don't fool yourself into thinking that means the cars can "self tune"

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post #10 of 13 Old 02-07-2009, 11:40 PM
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yea for sure get some headers i have the gt spec i think ver 2 with uppipe with a intake and downpipe and a CBE and my friend that work in east cost greddy before they close down help me install my bosst contr at 16psi and um liking it a lot i mean for a wrx u gain some nice power but the downfall was the headers i got was more high end power i lost some low end ... so make sure u do some research of what kind of power u looking for low or mid or high
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post #11 of 13 Old 02-08-2009, 03:19 PM
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DumDum is right as most always.. LOL, The thing to keep in mind is that NA motors work by vacum. They actually suck in air. As the piston is in it's down stroke the intake valve opens. The movement of the piston sucks air through the intake system into the piston chamber. Now on the other hand our turbos overcome this by forcing air into the motor thus adding power. Now when you free up the flow of air out of the motor it makes it easier and faster for the air to enter the motor allowing the NA car to make more power. A turbo car will also benifit form the header just not as dramatic as the turbo is already forcing air into the motor. This is one of those situations where power is overlapping so you don't gain as much..

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post #12 of 13 Old 02-08-2009, 06:23 PM Thread Starter
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Don't you need back pressure though? Like I know to much is no good hence getting more free flowing exhausts and what not, but when my friend got a exhaust on his Integra I told him not to get to big of a exhaust (He has 2.5 inch piping, 4 inch tip) because I figured if it was to free flowing it'd just be a giant air pump essentially...Is that true?

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post #13 of 13 Old 02-08-2009, 08:33 PM
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Don't you need back pressure though? Like I know to much is no good hence getting more free flowing exhausts and what not, but when my friend got a exhaust on his Integra I told him not to get to big of a exhaust (He has 2.5 inch piping, 4 inch tip)
No,you don't want any back pressure.It has to do with exhaust velocity.To big an exhaust kills the exhaust's velocity.There are a ton of articles on line about exhaust systems.

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