well i know they are pretty much the same header, but with little differences. here's what i've come to the conclusion of so far...(before i start, please just keep these two in mind, no mugen, or toda or any of that other stuff no one can afford, just these two.....thanks )

anyway- the 4-1 nonjdm has a 2 collector ( just like all other headers ) and the jdm has a 2.5 collector. this larger collector obviously has more flow which produces less backpressure ( bad on valves ) yet still gets great HP at the high end of the spectrum. (where i want my power. already have ITR IM, along w/ cai, hi flow cat, and exhaust)

- the 4-1 design is meant for high revving, but kills torque. will the 2.5 colelctor eliminate low end grunt ( or what's left of it on my b17a ) completely seeing how it's using both 4-1 design and big header collector?

i know toda makes a 4-2-1 w/ 2.5 collector which is supposed to be optimal b/c of the torque of a 421 yet the high end of a 4-1.....so the jdm 4-1 and 2.5 collector. really big power or what explain------, what are the power differences between the two: dc 4-1 nonjdm and the jdm? has anyone actually done a swap 1 to the other2?

the only other thing i can think of is carb exempt, but who really cares about that anyway? i already passed echeck ( smog stuff ) and they pulled me up on the rollers and messed stuff up allready, ( header - cat pipe ) so it's time for a new header, but i've kinda got a deal on a dc 4-1. if nothing else gets unanswered, answer this. is there ( explain ) a big difference between the 2? thanks for yer time. --lata


[Modified by RedStarGsr, 7:17 AM 2/19/2002]


[Modified by RedStarGsr, 5:06 AM 2/20/2002]

 

http://www.automotiveperformanceengi...om/header.html


[Modified by passion4healing, 11:50 PM 2/18/2002]

 

That basically sums it up.

 

It doesn't show the difference between the original question, DC 4-1 vs. DC JDM 4-1.. thanks for the mad smilies though..

The primaries on BOTH headers are the same, as well as the flange.. The only difference is the collector.. So to answer your question, if u have a setup that would gain from a 2.5" exhaust, get the JDM one, if not, stay 2.25" and get the regular DC..

My current setup includes cams and nitrous, with headwork and bigger cams soon, so I'm running the 2.5" collector and 2.5" exhaust.. Hope this helps!


[Modified by HKxBlur, 9:51 AM 2/19/2002]

 

hey thanks jeff--- that header test is cool, but it doesn't have the regular dc 4-1 on it, so it doesn't do me any good. if anyone else has any thing feel free to chime in. --seeya

 

anyone else?

 

JDM DC--- You can play with the bigboys

Regular DC--- Playing with the kids

 

playin with the big boys? uhm......i believe that saying goes.....

turbo-- playing w/ the big boys

n/a inline 4's....um.....

not to knack my own type but......i think we all know to build an agressive all motor integra, takes a lot. ( at least a daily driver, sure anyone can throw a b16a in a purely gutted crx w/ intake, intake mani, cams, internals, jdm 4-1, test pipe and exhaust and run low 13's. even try a 50 shot and go easily into the 12's. )

didn't mean to sound like an AZZ but whatever. but thank you for your honesty. later.

 

the DC JDM has a 2.5" collector

 

brilliant -- dan get the jdm dont waste your time
-robbie

 

i know the jdm collector is 2.5, hence my first thread

-robbie--> tooo late, no jdm for me. you gotta strike while the iron is hot, the only question now is to sell my soul trying to find someone who will trade me for a jdm ( which no one will ) so i'll just stick w/ my good ol' regular 4-1s. remember, there was a time before dc jdms.....

 

I didnt want to risk not passing Smog, so I went with the DC 4-1. I'm very satisfied with it, and don't regret it.

About that "Big Boys" comment, that was juss stupid. So does that make an Integra LS with JDM header, a BIG BOY group? And a GS-R or Type-R with DC Header, Little Kids group? Uhh.... I don't think so-

 

big boy group = big $$$

 

GS-Racer---- thanks for the input friend- ( nice e/t by the way ). did you put that header on when you had your intake and exhaust? just wonderin how much torque it actually robs ( and gives back up top! ) have you ever ridden in any other b series motor'd cars w/ a jdm dc? my bro has one ( but it's kinda hard to tell by just riding it.......plus i didn't ride in the car b4 the header ..so.. )

there is something nice about having a 4-1 with that nice little carb exempt little tag--

does anyone else know anything about too little back pressure ( from a 2.5 collector and test pipe / exhaust ) being bad on the vavles-- now hurting my valves probobly isn't a smart idea especially for a 101xxx motor- who knows may im just trying to convince myself one way or the other. thanks anyway though guys. --lata

 

when was the last time you ran at edgewater anyway dan?

 

indeed there was...however the future is now jk dan. your car is faster than mine either way.

 

too long ago! i'll be going up there sometime this spring though, i'll let everyone know. im hopefully gonna attempt to put the this thing on friday night, as in an all nighter, and i dont plan on doing anything else. not too much work should be done, removal of old header ( easy, for it's two piece ), remove cross member ( 4 19 or 17mm bolts, ) and cut it w/ powerdisc ( if it even needs to be cut ) and slide it up in there, bolt the flange up, and clamp a pipe down until i figure out what im ognna do w/ my cat. it seems shorter than my bro's dc jdm ss 4-1, but his is for a type r too, hopfully it will clear the oil pan on mine, only time will tell. after helpin him w/ his 'custom' exhaust, and that header, the nonjdm looks sooooo tiny. oh well.

DOES ANYONE HAVE ANY KNOWLEDGE ABOUT 2.5 COLLECTOR HAVING TOO LITTLE BACKPRESSURE, HENCE BEING BAD ON VALVES? i'd appreciate it. later guys.


ps-- when you gonna slap that itr rear sway bar on? it should be nice- (you have YET to let me ride w/ the mugen bar! )

 

We just got finished putting a DC JDM 4-1 on a '92 GSR, it had a DC 4-2-1 on it before. We had to notch the cross member quite a bit, but no big deal. The car lost a lot of its low end but makes up for it on the top end. We also think there is an exhaust leak in the 2,5" test pipe, so when we get a new one made i'll let you know if it helps.

Times 1/8 mile
w/ DC 4-2-1 9.6@72 2.2 60ft
w/ DC JDM 4-1 9.82@73 2.4 60 ft (was blowing the tires off had a broken front motor mount)

Haven't heard about the JDM hurting valves, but we put Nitrous on it and the first night it burned a valve.

 

ill be slapping on an itr rear sway bar after:
camber kit
header
and cat

so ive got about ~500 to spend be4 i get the itr rear sway

let me know when you go to edgewater -- i need to see

if u want help with the header im not busy friday -- we could even do the rear camber guy for my car....

 

cashed-- thanks for the info man. sucks about that valve man. who's car was it? i might know em-- anyway-- yea notching the xmember aint a big deal, but here's my question. first you have the header collector come out, then you have that metal thing that goes around it ( the donut gasket guy... c'mon ) then it feeds into your stock cat which has that female looking flange on it to goes from big to small ya know? well w/ my aftermarket cat welded on about 6" later, i have to make an extension piece. not a problem , i just want to avoid welding to the actual header, i plan on welding the pipe to the cat, yet trying to find a 'flange' that will go over the stock header collector and into just a regular size pipe 2" or 2.25" pipe.

im basically looking for this :: but not in a 2.5 ( this was taken from http://www.inlinefour.com anyone know of anything like this.


also cashed--- how'd that gsrr pull after that header? i'd expect nicely..muah.

robbie- sounds good to me- lemme know when those (c8's?) get in. --lata


EDIT:: this might be a better picture


[Modified by RedStarGsr, 10:37 PM 2/20/2002]

 

Haven't ridden in a car with the JDM header, but I've heard you can feel that much difference.

Also, you don't lose gobs of torque on the bottom end. Trust me, you can't even feel the difference. But you can definately feel it pull harder in the upper half. Go with 4-1. Either JDM or DC, you will like it-

 

dan are you installing the header tonight? (weds night) nice job playing the prs by the way

 

robbie, my parents are out of town for the week. I have a dc 4-1 header sitting in my garage. it is now 5:06 in the morning. yes, its installed .HAHA!! cutting the crossmember was such a *%#@%!!! , not really, but actually fitting the 4-1 up in the engine bay ( w/ no one to help ) was a little difficult. my face is black, my fingers are really really black, and im tired as hell. i probobly wont go to school tomorrow for the first few bells..haha. --later guys.

ps- i found that header reducer thing at autozone for $10. just in case anyone ever runs into the same scenerio...

edit:: oh yeah, thanks for the compliment- she's my other baby, just cant decide which one i like more....hmmm....well if i sold the car i could buy 2 ( or 3 ) prs's! ha. anyway, thanks. seeya.


[Modified by RedStarGsr, 10:15 AM 2/21/2002]

 

i need to go for a ride TODAY -- u take it for a drive i hope?

excitement.

 

robboh- i just woke up ( 2 ). my brother set my clock for 4 hours fast, so when i woke up ( 20 mins ago ) it says 6 something. i wasl ike holy crap! nah, i didn't take it for a ride last night, way too late, but we'll see about that ride today.

robbie- definately get that comtech. ( is it 2 piece ) one piece was such a pain to install, but i bet it would have been a whole lot easier w/ 2 people. see ya later man.