fbp_hatchy

Hello,

First off I'm sorry if this topic has been covered a bunch of times.

I just bought a DC sports ceramic header for my SiR and I'm wondering if its better to get the 4-2-1 or the 4-1. I've heard that the 4-1 is better for high end torque with the b16a2??

Thanks for any help!

Gunmetalef

4-2-1 is usually cheaper and more midrang to top end power good for street use and its much easier to install than a 4-1 header
and a 4-1 is a one pice with better flow... more power noticeable in topend of your rpm's generally used for track

B18C|

4-1 is for high horsepower cars, 4-2-1 is good enough for you, spend the extra money on hi-flow cat or test pipe

imported_JookSingKid

Search is your friend

There should be no price difference between a header that is 4-2-1 vs a 4-1

4-2-1 is more mid range power

4-1 is for high end power

I think mid range power is more imporant than high end power

most likely for your application, you won't notice a difference between a 4-2-1 vs a 4-1

Mugen Power

. think about it for a second. if 4-1 headers make more power than 4-2-1, then why are the best headers on the market 4-2-1? has anybody heard of SMS, Hytech or DTR? they are the most serious headers on the market, and they are all 4-2-1, yet, everybody says 4-1 makes more power? somebody needs to do some research.

bbarbulo

iTrader: (2)

someone needs to look at some dyno charts before they speak.

4-2-1 and 4-1 usually dyno about the same throughout the powerband, except the 4-1 makes 2-3 more hp in the upper rpm range.

Most headers actually lose power... only a couple of them make about 5-8 hp overall. They could prolly make a little extra if the engine gets tuned. But before you buy (too late in your case), you need to look at some Honda Tuning, old Sport Compact Car magazines. Some of them do header shootouts and show dyno charts and all. I remember back in 99/00 when the SiR came out, there were LOTS of these comparos, headers, intakes, exhausts, cams, etc etc. Dig through some old issues of SCC.

Gunmetalef

i have the best of both worlds.. i made my own flange to match my stock 4-2 piece header... but the "2" part begins at the flange.. but from there it goes to 1 i'll post a pic later.. but its really cool

imported_zc_hatch

dan its still a 4-2-1 lol its just the -2-1 is really close together

imported_My93Civic

Since you won't be able to tell the difference don't buy them at all. Everyone is just wasting money on a header.

imported_zc_hatch

you won't be able to feel the extra 2-8hp you get...
but its there
if you add alot of things @ the same time you might

Mugen Power

what? if the best headers, actually, the most proven, low 10 second drag cars use either SMS,Hytech or DTR. are you saying that if there design was 4-1 instead of 4-2-1, it would make more power? come on, Barbie, you can't be serious? i've seen header tests, dyno's and all that. 4-2-1 headers, when designed properly makes more power under the curve, peak hp & peak tq. anyway, Titanmotorsports had a shootout a while ago on HT. check it out if you think that i'm wrong. actually, i have an issue of SCC from 99' it tested most header on a mildly modded gsr. the dc 4-2-1 made the most overall power. it beat out Mugen, Greddy, Neuspeed, Rs*r, Pacesetter and a few others. believe what you want, the proof is out there. have you ever seen a dyno overlap of the T1-R 4-2-1 vs. JDM DC 4-1? the dc made 2 whp more at peak, but, from 2000-7900rpm the T1-R made a massive 6-8whp more. that was during the great header test that ep engineering did years ago. trust me on this one.

Mugen Power

he means, you won't tell the difference between the 2 aftermarket headers. a header is not a waste of money. it is if you buy a Ractive, but, if your head flows, it will make more power than the oem manifold. that was a whack statement, unless, you are saying its a waste because turbo is the only way to go. if that's the case, then yeah, a header is a waste.

1990da

i find the 4-1 sits lower den the 4-2-1. thas in my 90 da though. i dunno if its the same for other cars.

fbp_hatchy

hey guys thanks for all the info. I went with the DC ceramic 4-2-1. Should be at my door this week sometime!

imported_JookSingKid

Output numbers are never the most important thing in creating power.

Power delivery IS

the shape of the power band and the throttle response.
you can have huge numbers but if takes you forever to produce them and the response isn't snappy then its pretty useless power in my books.

KAMUFI

many other mods you can do than a header to make your car faster, more powerful, all that jazz.

cough, cough, hondata, cough

imported_kane2k

m power, why bring up 10 sec drag cars in response to a question about a daily driven Civic? The difference between 4-2-1 and 4-1 is a subtle airflow difference which can distribute power into different parts of the powerband. A 4-1 header would be least restrictive so at high rpm and high flow it shows modest gains. This lack of restriction though will hurt a little in the low to mid range when the added backpressure, but overall high flow rate, of a 4-2-1 gives it a boost in the midrange.

Back to 10 second drag cars. The engine in a 10 decond drag car runs significantly differently than a stock b16. If you are talking about 10 sec NA civics then its a high revving motor which obviously would be better off with the 4-1 for the reasons stated above since you're going to be redlining it. A daily driver is going to spend most of its time at mid rpms though so a 4-2-1 would be better and faster for that application, unless you drive around at 6000+ rpm.

Mugen Power

you wasted your time saying all of that ****. i referred to 10 second cars just to put things into prespective for everybody, which is....4-2-1 headers, when designed properly, make more power. as for you saying 4-1 headers are less restrictive a blah, blah blah.... you are mislead. if you look at a dyno with a well designed 4-2-1 vs. 4-1, you'd notice that the 4-2-1 makes more power under the curve most of the time. 4-1 headers usually make more power up top (7500-8200), but lack power from 2000-7500rpm. its simple math. no matter how much power the 4-1 makes over that samll 700rpm window, it can't make up the 3-5whp & wtq lost over a 5500rpm ******. anyway, i own a modded b16 and i know for a fact that 4-1 headers are overrated. when you take into consideration that if you purchase a jdm dc 4-1, it will bottom out within 24 hours of placing it on your car is enough for one to realise that it is a bad investment. believe what you want, it doesn't phase me...actually, this reminds me of the ITR IM vs. p30 IM. on a b16, the ITR IM gets it *** handed to itself from 2000-8200rpm...(i'm speaking b16, remember) but, the ITR makes more power from 8400rpm and up. does the ITR makes less peak whp? yep...what about peak wtq? yes, once again...so why does everybody want the ITR IM on there b16's? because they don't know ****. 4-2-1 headers are better...end of story. don't get fooled by VTEC. everybody thinks that because it designed for high rpm means that you should purchase a high rpm header. this is the #1 misconseption. VTEC lacks tq and that's what the focus should be, retaining torque and not sacraficing any. one day you'll learn. JSK said it first, though.

imported_kane2k

lol I misread, I thought you were pushing for 4-1 as better. As for me being mislead, I said everything that you did, i.e. better airflow at the limits of the engine for the 4-1 with reduced mid range gains, so we're on the same track. You just don't seem to think that there are well designed 4-1's out there. There are, and in certain cases the gains that they give at high rpms can offset their lack of midrange gains. Not always and not on every engine but my point is that the difference is small and the best choice depends on your application.