That's what I was thinking. 4-2-1 allows for a less turbulent flow of air through the piping versus the 4-1.

 

I guess the thing I find unusual is if the 4-1 design gives more peak power then why do the TODA and DCRH on the RSX-S both use a 4-2-1?

 

It's not easy to determine which is better. One company's 4-1 might be better than another company's 4-2-1 for the same application and vice versa. It has a lot to do with piping length, size and pipe bending/routing design and the current mods of your engine. Also, how well one product works with the existing state of tune.


The TODA header seems to targetted for certain modification.

http://www.todaracing.com/products/h..._manifold.html

 

OK I wasn't actully imply anything about header dia. goes smaller thru the end. I was just trying to understand jlukja question.
Anyway, why are you saying that 4-1 is more restrictive than 4-2-1 anyway? From my stand point of view I can't really see it. Please clarify. I might be wrong, but as Stoke put it I was always taught that 4-1 gives more more than 4-2-1 in high RPMs.

When it comes to firing order mixing up the exhaust stream creating a turbulent in the 4-1 that is not necessarily true. With a properly designed 4-1 you can actually avoid that. Actually both 4-2-1 and 4-1 can avoid that. Being a 4-1 header you can design it to have an equal length runner so that once 1st is fired it'll be immediately followed by 3rd then 2nd and 4th, correct me if i'm wrong on the firing order. So, if we take a closer look during the engine cycle at the merge of the 'properly' designed 4-1 you'll see that once 1st goes it'll be followed by 3rd etc. Exhaust strem won't cross at that point at all.

As for why Dan's Toda is 4-2-1 not 4-1 while it's making massive power, that I can't answer.
There are WAY too many factors that could contribute to this reason, as JTso put it.
I take that 4-2-1 is much more simpler to design and manufacture than 4-1 by just looking at it, this is just my speculation. Since 4-1 costs more TODA decides to use 4-2-1 to control cost? Cuz that thing cost triple what the market is running already so TODA wants to sell their headers, not a bragging rights. Also, as JTso said about his SC car, 4-1 could have some packaging issues or it might be too low for a daily driven RSX.

You will also have to consider that everbody wants to make profit; therefore, their products must sell and make profit. As a result, everyone will aim for highest peak power output. Just ask yourself, would you rather spend money on header that produces 10 lbft of torqe at 3500 RPMs or one that makes 10 hp at 6000 RPMs. Of course, you'll pay for the one that gives you more power! You want a header that will give you some bragging rights to your bar buddy that your car is now making 10 more hp at the dyno. No body gives a damn about header that makes 10 lbft at 3500 RPMs. Also, kids these days want something that looked good. Instead of putting money on making 4-1 they diverted that money to a better material such as stainless steel, flashy and shiney looking, to a 4-2-1.

 

Dan could be right with one type of 4-1 and could be wrong with another type of 4-1 header. It all has to do with the "acoustics" of that header. A header works similarly as a church organ does.

And before I go into all sorts of crooked explanations, I'll research more on it and get that info out latez.

 

Reading all of these posts makes my head hurt

with Jtso & Dan, time for a header shootout!

Is there an aftermarket 4-1 availible though, the only aftermarket ones I've seen are all 4-2-1.

 

Technically speaking the 4-2-1 header moves the exhaust gas way more effectively into two seperate chambers instead of one in the 4-1... (4-2-1 is much better)

 

Thank you, Dan.

To the rest of you:

 

technically speaking

 

It all depends on the application. If one design is truely better than the other, why do header companies even bother making any other designs?

 

Just look at some other dyno's man you can't base everything you say off of comptech. Comptech sucks for power per dollar.

 

I didn't base everything I said off of comptech, just as Dan didn't. That was just one example. I couldn't give a shit about comptech. Eat my ass.

 

Hope I'm not upsetting Mr. "I have most power for a TSX on this board"

 

Only trying to be helpful

 

It's perfectly okay to agree or disagree with one's opinion. No need to be disrespectful to other members just because they don't agree with you.

 

Mmkay, I did my research, and fell upon an old classic by SCC, the "Suck, Squish, Bang, Blow" Series they published back in '99.

I thought the section about headers was pretty informative, so I took pics of them, and here goes:









Hope this helped solve the debate...

 

Good find sauceman!

 

Yeah, that was a great read.

So I guess they only consider the primary runner length for rarefication then? The 4-2 lengths I mean, instead of including the 2-1 run into the final collector. Makes sense as that would be all the exhaust port sees as a resonant cavity.

We need a weekly thread like this or something. /nerd

 

This thread really gets everybody jumping!!!
Hahaha

 

I appreciate the help guys, although apparently the whole issue is still rather confusing. And yes, I was being serious!

Slats

 

so according to the article..4-2-1 has a wider power band and it has LESS peak than 4-1. So with that being said 4-1 has higher peak where 4-2-1 has better everything else. Hmmmm isnt that what I said earlier??? Don't get an attitude man we are here to help each other not be assholes. Most of us have been here for a long time. But we are all still learning more and more about the K series. Don't dog us because we disagree.

 

Is there a Cliffnotes version of this article available?

Thanks for the good read Sauceman, way to dig it up from the archives!

The funny thing is, I think at one point I had that issue. It's probably long gone now though.

 

Hmm. Then what about a 4-2 header? Where would the gains be?

 

A 4-2 header would be hard to implement on a road car because you'd need 2 catalytic converters and there's not a lot of space for them. If you went with straight pipes you might be able to do it.

 

Even then, I don't know that it's an optimum setup.

Then again, you have 1 exhaust per valve setups like this one :

 

Is that a spy shot of the new 2007 TSX?

 

Damn! such monster!

 

Who'll need a hondata then?

 

Looks like Tim "tool man" Taylor's lawnmower.

 

Hmm. But it seems like the Spoon header for the EuroR is 4-2? So the downpipe would be 2-1 merging or like you said 2 catalytic converter? Also would the torque band be smoother/higher than a normal 4-2-1 or 4-1 header?

 

The Spoon header is actually a 4-2-1 and the term downpipe is more commonly used in the pipe after turbine housing of a turbo in a turbo charged cars.
Also the Spoon header still uses the same cat so the header still has to merge into one pipe.

 

The Reason why they make two different kinds, is because one is more fuel efficient...

 

Please!

If you're just gonna post anything straight out of your ass, why don't you just not post?

 

 

Does anyone know the difference in power gains when comparing the Comptech and DCsports headers? The DC is less than half the price of Comptech, but how does it compare?

I've heard about the flex pipe issue concerning the DC' but what about overall power gains compared to overall build quality? Any help would be greatly appreciated...

 

The DC sports will yield more power.

It had initially some quality issues, but according to Stokeless, the problem has been resolved.

 

Thanks. That being said.... why would anyone go Comptech other than brand whoring (lol, jk)? Cheaper and more power is definately the route I'm going to take... After I get my Reflash...

 

http://vtec.net/articles/view-articl...icle_id=348704