inspyral

You can get a JDM DC header for about $300. The Mugen header runs about $800. I would go with the DC, personally.

ferrealb16

true, but...
headers are one of the first mods, but do it right. i wouldnt suggest dc, apex, mugen, or oem. save a little bit more money and get a custom header done, or look for an a&n pro header. there are 2 things a 4 cylinder header needs to make it worth money-no mandrel bends and telescoping collector. mandrel bends take away from the velocity of the exhaust, therefor you want a header with formed 90 d. elbows. read up, this was true 5 years ago in superbike racing. telscoping collector picks up torque as well, without sacrificing top end power. it picks up torque by increasing velocity. this has been proven effective in the enzo ferrari, a 250,000 dollar car.

1stGenCRXer

:eh: Bends period take away from flow velocity, but a mandrel bend is something to stay away from? You have to be kidding me. Ah, 5 years ago... sorry, I stay a bit more current. 90 degree bends are second only to 180 degree bends in their ability to rob the exhaust of heat by conduction, reducing velocity [not to mention the fact that the "formed elbows" you refer to are actually mandrel bent sections with just enough material for the bend, instead of the entire length of pipe most aftermarket headers have]. In fact, the fewer bends you can make, the higher the average velocity will be. A quick look at current superbike headers show that... yep, 2 bends total, one out of the head downward to clear the riders leg, and another up and to the back so as not to scrape the ground while giving the measured [and desired] length the engineers want to make power. For those keeping score at home, the first bend is 90, and the second is more in the neighborhood of about 80 degrees, with about 14 inches between the two. Even Ferrari's 2002 F1 engine had mandrel bent sections in it's headers, composed of 110 degree bends, and even some 45's, quite a range really. The most important thing is tuned and equal length though, not how much the bends are. and here... I just don't even know what you're saying here. The Ferrari Enzo was designed more as a technological statement than anything, and whatever isn't plugged into the system's computer was designed to make a visual statement while still being functional, and quite frankly, sharp bends catch your eye, and since a tuned length header is the most important aspect, you can get away with multiple sharp bends as long as the cross-sectional measurement stays the same.

-KangaRod-

nothing could be further from the truth. When you buy a header that two copies is made of, you can split the R & D cost by half, and so on untill you've sold thousands of them as DC has. History has proven mass production, as a general statement to be much more cost effective. If it is cheaper you can either save money, or get more bang for your buck, either way, you'd be better off getting a name brand one. I like DC.

qtiger

First, the Enzo sold for $650,000. If you are going to try and impress us with your knowledge, at least know what you are talking about.

Second, spending $1000+ on a custom header on a $3000-5000 Civic with a ~100 HP D series engine is generally not in the average Honda modder's plans. There are several brands who make very good mass produced headers, with power numbers similar to much more expensive products. The 1-5% gain a custom header will provide is nothing in comparison to the gains that could be achieved by spending that money on other mods.

If you want a good performance header and are willing to pay the price, Hytech Exhaust or SMSP can provide a very high quality product without the hassle of true custom work.

ferrealb16

wow, sorry i got the price wrong on the enzo. im not concerned about the price, just the technology.

bends take away from flow. mandrel bends creat an odd shaped figure. because of this, the exhaust flow doesnt flow as smoothly as it would if it were being pulled/pushed thru a constant radius bend. and how do you get constant radius bends? you contact a tubing fabrication house and buy either 90 deg bends or donuts.

you stay current huh and dont give history a second thought? ever heard the phrase history repeats itself or you could learn from your elders? well hello, learned something from highly competetive superbike racing and applied it to import racing.

take a look at ericks racing, check out his header that he has properly tuned and make your car fast.


what is up with the gang mentality on this board? i simply come here to ask a question, give my advice/opinion and you jump on me like i were a virus! you must all be liberal democratic dictators, meanin if its not what you think, its wrong.

MrFatbooty

The reason people have ganged up is because you show up out of the blue and your choice of words (at least to others) seems to indicate a condescending tone. Joining the conversation with a bit more tact and sharing your ideas and opinions without belittling others tends to be a better way of stepping in.

1stGenCRXer

:eh: A mandrel bend is accomplished by inserting a mandrel the same size as your exhaust and using it to guarantee the inside diameter doesn't change. Are you thinking of crush-bent tubing? The difference between formed elbows and mandrel bends is so slight it's almost laughable.Let me put it this way. If it was so great, it would still be used in racing. As far as engines and competitive racing goes, history is all apart of the recipe for making power, where you learn what to add and what to leave out. If you want to talk about highly competative, look into the world of kart racing. It's gotten to the point in 4 cycle karting that high HP engines have about a 15* bend coming out of the head on an otherwise straight pipe. Why? Because they figured out that's the angle needed for the naturally swirling gases to exit with the least back pressure, which is a necessity on a flat-head engine. If you get into the restrictor plate classes, they're using 360* bugle style pipes because they run stronger with the added length that you can only fit within the rules by turning that much. Back to motorcycles, or 2-cycles in general, to make the most power you need to be able to handle the sound energy from the exhaust port the most effectively, with your divergence and convergence cones after the tunable section of flex piping. The header pipes are still mandrel bent.My car does fine, it won't break any records, but it will get me to work with some fun, and still pull over 35 mpg. That's what we do here, talk about streetable engines because most people can't afford to spend all their money on engines that last less than 20,000 miles. Well, lemme see. You come in here spouting off things that no street engine builder would ever consider doing, trying to drop names and cite professional techniques, and pretty much use those as your only basis for your suggestions. I'm all for new ideas, but your suggestions just don't add up to logical thinking.

ferrealb16

how do you belittle someone thru a computer screen? i dropped the knowledge.

im the kid on the block who took apart the briggs and stratton engine on his minibike to tweek it so he could run a sprocket with less teeth, thus more top end speed. or im the teenager that sat thru drawing class creating a go-cart frame so he could use the 250cc 2stroke engine his neighbor used to have til he snapped the bike frame in half. studying sisters engineering/math books so he could create custom headers for projects such as the minibike and go-cart. in fact, im the guy who refuses to pay a college professor to teach me something that i can pick up a book and read/learn for myself.

just simply tryin to drop the knowledge and help create faster civics the world over.

MrFatbooty

That's great you're motivated to learn stuff. It's good that you want to share your knowledge. Attitude still comes through a computer screen. You type words and they convey that attitude. There's no need to get into a lengthy "I'm right, you're wrong" exchange. If you believe something is correct, show your reasoning and see what people have to say about it. If someone disagrees, fine, they disagree. It's only someone else on their computer, they don't know you and they don't mean to insult you. This is a pretty chilled out place, no need to be the supreme master of automotive theory or anything like that.