Ok - There is a big debate amongst some of my buds about how much the H22 factory manifold sux. Apparently NO one makes a header for the H22 with a 2.5" collector? Here are a few points / questions I have. Please comment with your experiences:

- a 2.5" inch collector attached to the factory manifold would be a good idea?

- the DC sports 4-2-1 headers aren't very much different at all then the factory piece? How much longer are the primaries? Does ANYONE on earth have a before/after dyno of DC sports 4-2-1 headers??!

- would you be able to weld on a 2.5" inch collector to the DC sports header?

- are the greddy headers any good?

- would a H22 w/ cams benifit more from a 4-2-1 header, or 4-1? Doesn't the H22 not rev high enough to take advantage of a 4-1 header?

If ANYONE dynoed their header install, and thats ALL they changed (they had a catback before, I would assume) PLEASE tell me what you gained. I saw a dyno of a 4-1 header installed, and it lost midrange but gained practically nothing on the top end.

Am I the only one that thinks the factory manifold is good, and just needs a little TLC to make it add some good power?

BTW - I'm going with a custom exhaust so the 2.5" collector attachment isn't that hard of a job...

thanks for your opinions guys. Frankly, I'm not going to drop $900 on some mugen headers or wait a few months for Hytech headers (don't even know how much those are) when I haven't seen any evidence of gains from them.


[Modified by JDM LUDE, 9:21 AM 12/14/2001]

 

I know you said you don't want Mugen, but this might give you some ideas of the restrictions found in the stock exhaust. My plot of stock vs Mugen header and Mugen cat back...
https://honda-tech.com/zerothread?id=93591

Mugen has only a 2.25" collector and 2.25" cat back piping.

Andrew

 

By reading that I'm assuming that it was decided that the mugen header has a 2.25" ID collector?

 

First off, mugen isn't 2.25, its 60 mm...which equalts 2.36 inches.

Yes the stock H22A header is a very good stock header you do get gains from even a DC Sports replacement, at least on OBDI H22A's. I definately noticed more topend with my Greddy header. The revs flew to redline noticably faster in VTEC with adding the header compared to just having I/E. I have also heard from owners of DC Sports on their 4th gen VTEC's that they got nice gains also.

 

what size is the collector on the greddy header? Would it be possbile to change it?

 

2.0''

 

here is another idea you should consider....
get a JDM typeS header with JDM typeS cams. both will cost you less than a MUGEN header and you'll get more power.
typeS header is one of the best headers for H22A's. DC is not all that great, mugen is good but not worth the money. so instead of spending all your money on stuff you're not sure to get a good hp gain from, save it and in addition to those typeS cams and header buy yourself a typeS valve train (or some other good brand)as well to take advantage of the cams. i had to learn the hard way, you don't have to.a good exhaust for your car is TANABE hyper medalion. i loved mine, it gives good hp and its relatively quiet and street legal.
after all headers, cams, exhausts, and intakes i tried here is the best combo:
typeS cams, typeS header, hollowed stock cat, TANABE hyper medalion, AEM cold intake. this is all good for a sure 20+hp gain, depending on what else you got done to your engine. another good exhaust would be a 5zigen fireball with 2.5inch piping. its loud as hell when VTEC kicks in but it gives some respectable high-end power (its cheaper then tanabe too).
hope this helps... good luck.

 

Well i havent heard of one person who has bought an OEM JDM Honda Type-s header for their Lude here. It hasnt been tested or at least no one has shared results with anyone online. I also havent seen any sites that sell JDM parts selling these type-s headers either...so i dunno how realistic getting that header is for most of us

 

try this place http://www.inlinefour.com their number should be on the site.
they can get you any JDM part you want, and they carry a lot of typeS parts already.

 

Good questions! I have a Apexi WS and it's 60 mm piping and I had thought the same thing. I was thinking next year of having the collector on my N2 header modified to make 60mm the whole way through but I'm pretty sure nobody makes a 60mm collector or cat so I'd have to go to a 2.5" collector and then 2.5" cat to a 2.36" exhaust. I'm not sure how that would affect the flow. Anyone know for CERTAIN what the Type S collector and cat diameter are?

 

That would all be great if the Type S header were as much of an improvement as the JDM ITR header is on the B series engine, but it's not. It uses the same primaries and primary collectors and only changes the A pipe. If you think a grand for the mugen header is a rip off then how do you feel about paying $500 for an A pipe with slightly larger secondaries. Now that's a rip off.

At least the mugen header has longer primaries, which really benefit the prelude. I don't see JUN, Mugen or hitech using short primaries. Perhaps the Spoon primaries with the Type S downpipe would give some good gains but that ends up being more than the Mugen or JUN pieces which you would probably see more of a gain from.

Gabe

 

I saw a website selling the type S headers, but they were only selling the primaries... are they trying to rip people off, or are they actually different?

 

Is it a fact or just speculation that the Prelude gets better gains from a header with longer primaries??

Any info or links with information would be greatly appreciated.

 

I was under the impression that most cars will realize a mid-to-top end power gain with longer priamries - especially if they are larger in diameter...

The only real-world test data that I have seen that supports that on the H22a is the infamous Nam D. Vo's header dyno from way back in the ww.vtec.net days... Nam had a Prelude SH with an Iceman intake, DC sports headers, and Mugen cat back. He dynoed this setup. Later he switched the DC header with a Mugen header. The Mugen header has considerably longer primaries than the DC does. Nam got 5whp more with the Mugen header on the dyno than he got with the DC sports.

That dyno of Nam's has to be floating around some where... If anyone saved a copy of it, please email it to me and I can host it...

Andrew