Lets talk about headers

[JaMa]

OK, the time has come to get some headers for my WRX.

I noticed there have been quite a few posts on various types concerning headers from Cusco, HKS, Syms, etc. I am interested in technical explanations as to why equal/unequal length are better or worse, why 2-1/2-1 or 4/1 are better in your opinion.

I would also like to know from those of you who have them - what do you think? I would like to hear opinions particularly about Cusco and HKS as they are the two I am considering. What is your impression of driveability? Did you lose torque? Did your boost increase or decrease? Also, please state what type of up pipe you have just for comparison.

Was this mod worth your time/money?

Thanks in advance,

JaMa

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[WRXThis]

JaMa, Bret is the guys to answer these questions. Give him a call.

[JaMa]

Originally posted by WRXThis
JaMa, Bret is the guys to answer these questions. Give him a call.

Yes, I will talk to Bret, but I wanted a few opinions on this, especially from someone already running them. Hopefully someone here has something to say about this rather expensvie mod. There was a group buy on the HKS headers in particular in February in which at least 10 sets were sold. Surely one of these people has some opinion about the part other than "its pretty and I think it made power."

BUUUUUUUUMP---


JaMa

[WRXThis]

Where is big Al when you need him? He has headers!

[pbnj9786]

i personally waiting on delivery for the 4 into 1 maxim works equal length headers(no up-pipe needed), and from what i hear from dan(godspeed), "they put the cusco and hks to shame."

big al, i think is switching from his cusco to the maximworks as well.

true equal length 4 into 1 headers are supposed to scavenge exhaust the best, in which the exhaust gasses from each port come out at the same time. this creates a pulsing effect that is optimum in pushing the impeller of the turbo with high efficiency.

4-2-1 headers emphasize the midrange power more, while 4-1 are more focused on making top end power.

please, someone correct me if i am wrong.

although i cannot comment yet on first hand experience with the maxim works headers, i believe that headers in general is a mod that is worth every penny.

we will soon know for sure, right dan, hehe.

peace, pj

[davidm_sh]

Hey Jama-

Did you do a search? Not trying to be a smart a$$ . I just remember somebody posted some dyno results from about 5-7 different types of headers. I don't remember which one it was but there was one header that outperformed in both hp and tq. increase. All I know is that it wasn't Maxim, HKS, or Cusco. Some other brand I never heard of.

If I had the money I would probably go with Syms... just becuase it seems like the Mugen of Subaru parts [heh].

[pbnj9786]

cant get a link to work, but search for "guess what badass part" and you will find it.
the maxim works was not in this publication since it was just recently released after a year of r&d.

[Z1 Performance]

jam - uinless you are going with a monster turbo on the car, neither design will make any difference vs another.

In theory, the 4-1 should be a bit better up top, 4-2-1 a bit better down low, but in the real world, having tried both myself, you are hardpressed to find a difference.

Maxxim Works makes a very nice piece as well...but certainly nothing to put either the Cusco or HKS to shame, all are excellent top quality pieces.

adam
Z-1 Performance

[twinz]

I installed them at the same time I did the up-pipe and turbo back exhaust. ..no other mods, stock boost level...The difference was awesome. Much more power from ~4k rpms up and I had so much more response to throttle input even at low rpms. The car pulled hard all the way to redline with the power never falling off whereas with the stock setup the car fell flat at ~5500rpms. I cant speak fo the other headers but the HKS are beautifully made and utilize an excellent exhaust splitter in their 4-1 design.

After doing the turboXS stage 2 upgrade a couple of weeks ago and dialing in max 4th gear boost to 16.5psi, I really appreciate the headers and the rest of the exhaust system... it pulls so much stronger from all speeds and gears now...even off boost.

[JaMa]

Originally posted by Z1 Performance
jam - uinless you are going with a monster turbo on the car, neither design will make any difference vs another.

In theory, the 4-1 should be a bit better up top, 4-2-1 a bit better down low, but in the real world, having tried both myself, you are hardpressed to find a difference.

Maxxim Works makes a very nice piece as well...but certainly nothing to put either the Cusco or HKS to shame, all are excellent top quality pieces.

adam
Z-1 Performance

Adam et al,

Thanks for the input. Adam: the real question here is whether you saw a difference between the stock setup and one of the sets of headers. If you didnt, that answers my question...

Yes, David, I did do a search, but there has not been anyone passing judgement on the HKS stuff which is what I really want. In fact, based on pricing and appearance quality I am still leaning toward the HKS.

My big question has to do with pipe sizing and scavenging. More so than after the turbo, pipe size before the turbo has a lot to do with performance especially in the bottom end. The purpose of this thread was to ask to see if someone had any impressions of headers at all and whether or not they felt the difference in performance.

There is no question that mods like a bigger turbo, a chip from TurboXS, a boost controller, exhaust, etc. make a noticeable differnece in the car. I just wanted to know what the butt dyno told the i-club community about their headers. Better yet, did it have an effect on 1/4 mile times.

JaMa

[Zahnster]

The above mentioned header thread:

http://www.i-club.com/forums/showthr...at+badass+part

The Zerosports one sounds like it's quite good in either usage. Since it's more HP than torque, it's probably more top end oriented.

[JaMa]

I still didnt see any data on the HKS headers in there. I wonder if they really are almost identical to the zerosports in performance. I may just have to get the HKS and publish one of my infamous exhaust review threads.

JaMa

[Z1 Performance]

Both cars we did the manifolds on (we have done a few HKS and 1 Cusco) had VF30's, and BPM exhausts, stock IC's, stock ecu's, and an AFC, colder plugs, yaydaydayada....

Both the Cusco and HKS did the same...much better mid and top end, no difference down low.

That being said, Rigoli uses a stock STi manifold on his car...i did the same on my swap. But, not sure if the "old" heads are the same as the heads, cam profiles on a new age WRX....

I would recommend either the Cusco or HKS strongly...basically comes down to who has which in stock

[SpooledRex]

Ive heard that the Maxim Works Header is going to be discontinued...

Any truth to that rumor.
Chris

[JayGold]

A couple MWSIOC meets ago an I-Club member passed around a Japanese issue of Impreza magazine. The most interesting article was comparsions among all of the available headers on the market including results of the stock header. All headers were dyno tested and results were posted as was weight, design, closeup of fabrication, etc...unfortunately none of us could read the info we could only make out the HP & TQ figures + the weight.
The ZeroSports had the best bang for the buck, posted the highest HP & TQ of the group, Second was Cusco, I don't remember the third. However the ZeroSports was the heaviest, why you ask? Because it also includes the uppipe with no flange, which on our USDM units is potentially a weak spot. The Cusco had the best use of heat shields, and still posted respectable numbers. Other brands were Fujitsubo, HKS, and some unknown brands which just had poor quality...interesting considering all were Japanese fabricated products.
My overall opinion, after salivating on the pages for about 45 minutes was the ZeroSports design and craftsmanship, absolutely outstanding! Welds were above top notch in quality, expansion flanges that meet the block, and if I remember correctly, it's a true equal length design.
If I can find out who had the mag, I will scan the pages and post them here.

Jay

[Shik]

Here is some info I posted a few months ago on the Maxim Header, as well as different header designs overall. Might be useful, might not

"Also fellas, there are also different "styles" of 4-2-1 headers.

For instance, the WRC Impreza's headers have the number 3 cylinder meeting with the number 4 and then the number 2 cylinder joining with number 1, then both sets join together. Since the firing order is 1-3-2-4, this set-up will keep the exhaust pulses in order more as they hit the turbo

Most others I've seen, such as the ones pictured here, join the exhaust of each bank together. So 1&3 merge together, and 2&4 merge together. With this set-up, the turbo will get two exhaust pulses from the same bank of cylinders, then two from the other one, and so on and so forth. Obviously Prodrive feels it is better to get pulses in the "left side-right side-left side-right side" order instead of the much more common " left side-left side-right side-right side" order. Would it matter much on a street car, probably not a whole lot.

[wRx14pSi]

hey guys that have installed the headers with turboback exhaust.. how much louder is the car?? i am interested in headers/maifolds but dont want to wake up the whole neighborhood at 2am.

[DeliciouSpeed]

My understanding is that they tend to quiet the exhaust a little.

Ken

[twinz]

Originally posted by wRx14pSi
hey guys that have installed the headers with turboback exhaust.. how much louder is the car?? i am interested in headers/maifolds but dont want to wake up the whole neighborhood at 2am.

The Headers dont add anything to the noise level. All noise level increases or lack thereof will be in the design of the turboback exhaust, primarily the muffler. I used the MRT turbo back setup with hiflow cat, no resonators, muffler w/single 4in tip and the noise level is only a couple of Db over stock at most, at cruising speed seems quieter than stock. the sound itself is very different..deeper, stronger, more authorative and awesome under full boost high rpms..sings like a porsche.

[blxmjx]

I personally didn't notice any difference in exhaust sound level once the headers were installed. The only thing that I did notice was the boxer burble was more prominent at idle and cruising loads.

[JaMa]

Originally posted by blxmjx
I personally didn't notice any difference in exhaust sound level once the headers were installed. The only thing that I did notice was the boxer burble was more prominent at idle and cruising loads.

Well, sound is a great discussion, but did any of you feel a difference in power? Or was this a wasted mod?

JaMa

[nqwan]

according to god, my headers are ready (maxim). hopefully i'll have it within the next few weeks and i'll try to get it in as soon as possible...

[blxmjx]

Originally posted by JaMa


Well, sound is a great discussion, but did any of you feel a difference in power? Or was this a wasted mod?

JaMa

For me it was hard to quantify. I did my modding in stages. The first stage consisted of a turbo back exhaust system, cai, pulleys and a mbc. The second stage for me consisted of the cusco headers, vishnu uppipe, mrt upgraded top mount intercooler and a couple of other things. I did notice a big difference between the two stages but I am not sure which particular item made the biggest difference. I do know that my car pulls way harder than it did before any of the modding took place. The next stage of modding for me will consist of a bigger turbo and stand alone engine management.

[pbnj9786]

hey dan,
since nqwan's maxim headers are ready, have you gotten any pics of them yet that you can post?
pj