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Old 02-23-2008, 10:57 PM   #1
06blkwrx
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Default Equal Length vs. Unequal Length

Can somebody run through the pros and cons of equal length headers vs unequal length?
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Old 02-23-2008, 11:13 PM   #2
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Old 02-23-2008, 11:28 PM   #3
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unequal length= a little more low end plus boxer rumbel

equal length= more power overall but no boxer rumble will sound more like every other 4 cyl minus the raspyness

Last edited by novacivic; 02-23-2008 at 11:35 PM.
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Old 02-23-2008, 11:30 PM   #4
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the header faq linked above is all you should need to know.

to correct the statement above... equal length headers generally outperform unequal length headers everywhere... they spool earlier and make as much or more power up top as well. its a more efficient design, but it does lose the boxer rumble.
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Old 02-23-2008, 11:31 PM   #5
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Quote:
Originally Posted by novacivic View Post
equal length= a little more low end plus boxer rumbel

unequal length= more power overall but no boxer rumble will sound more like every other 4 cyl minus the raspyness

Thats backwards.

Quote:
Originally Posted by Wrinkleboi View Post
equal length headers generally outperform unequal length headers everywhere... they spool earlier and make as much or more power up top as well. its a more efficient design, but it does lose the boxer rumble.

I have yet to see equals that spool as fast as unequals. They do make more power in the upper mid and top end, but I have yet to see one make the low end that an unequal does.
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Old 02-23-2008, 11:36 PM   #6
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sorry beer + typing = doesn't work right
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Old 02-24-2008, 12:06 AM   #7
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Quote:
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sorry beer + typing = doesn't work right

been there
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Old 02-24-2008, 12:10 AM   #8
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What provides the special sauce in ELHs? The smoother flow?
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Old 02-24-2008, 01:35 AM   #9
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What provides the special sauce in ELHs? The smoother flow?

Its how the pulses line up in the pipe.
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Old 02-24-2008, 01:40 AM   #10
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Quote:
Originally Posted by novacivic View Post
sorry beer + typing = doesn't work right
im there right now,lol.

ive heard acouple wrx's with equal length headers and its just not the same.
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Old 02-24-2008, 01:51 AM   #11
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since the collectors are usually shorter, I beieve unequal lengths headers spool faster.

that said, if you want quicker spool and equal length, twin scroll does the job.

Also like to mention equal length is quieter. Also, listening to an equal length header subie next to other 4 cylinder cars shows they di not sound like other 4 cylinder cars, but doesn't have the rumble.
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Old 02-24-2008, 02:49 AM   #12
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i have a fujisubo el header...i can definitely say it spools faster. i think it matters how the collector design is, the fujisubo is 4-2-1(the 2-1 part occurs right at the uppipe flange.
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Old 02-24-2008, 10:21 AM   #13
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Quote:
Originally Posted by Davenow View Post
Thats backwards.




I have yet to see equals that spool as fast as unequals. They do make more power in the upper mid and top end, but I have yet to see one make the low end that an unequal does.
my synic motorsports headers spooled several hundred rpm sooner over ported OEM manifolds. that was before tuning as well. the problem was that i had two sets crack < 6 months after installing them.

i'm through with with stainless manifolds on subarus.
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Old 02-24-2008, 10:47 AM   #14
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Over OEM, but over aftermarket unequal headers?

To be fair, all the equal headers I have experience are earlier models. Maybe they were a different design??
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Old 03-04-2008, 07:25 PM   #15
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Quote:
Originally Posted by Wrinkleboi View Post
the header faq linked above is all you should need to know.

to correct the statement above... equal length headers generally outperform unequal length headers everywhere... they spool earlier and make as much or more power up top as well. its a more efficient design, but it does lose the boxer rumble.

what do you mean by losing the boxer rumble with equal length? I used to have headers + up pipe combo (not sure what brand) and they made the car sound way louder.. is that what they're talking about? Sry, Newbie here.
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Old 03-04-2008, 07:32 PM   #16
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Unequal keeps the SUBARU DEEP RUMBLE. Equal Length makes it sound more like a regular 4-Cylinder Turbocharged. But people go to the Equal Lengths to make more power because it balances out the exhaust pressure. But some Equal Length headers do sound very nice. No subaru rumble but they aren't bad either. Aslong as they don't sound like fart-cans we'll all be okay.
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Old 03-04-2008, 07:34 PM   #17
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Quote:
Originally Posted by RingU View Post
what do you mean by losing the boxer rumble with equal length? I used to have headers + up pipe combo (not sure what brand) and they made the car sound way louder.. is that what they're talking about? Sry, Newbie here.
He's not talking about louder. He's talking about the deep boxter rumble. Go to youtube there are some comparison's on headers. You'll know what he's talking about.
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Old 01-25-2009, 01:20 PM   #18
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What up fellow subie guru's.. I will be installing an Ultimate Racing T3/T04E turbo kit on my 02 WRX. The turbo is a 0.60 A/R and was wondering what header to go with, equal or unequal? Any suggestions???
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Old 01-25-2009, 01:37 PM   #19
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ok ill give you the bare bones diff. .

EL = more power (10-15hp) more efficient
UEL= sound better

imo i would rather have 15hp less and keep my subaru sound thanks
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Old 01-25-2009, 01:40 PM   #20
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Quote:
Originally Posted by ChandlerWRX06 View Post
imo i would rather have 15hp less and keep my subaru sound thanks
What he said. If you are at ~400whp, I'd rather keep the sound then get another 15whp.
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Old 01-25-2009, 02:55 PM   #21
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I have talked with my tuner about Headers and the ones he likes are APS, Fujitsubo and Tomei. APS has a new header out that shouldn't crack like the old one.
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Old 01-25-2009, 06:59 PM   #22
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Performance goes to equal lengths. It will out perform the unequals no doubt.

SOUND is a personal preference.

This is equal length header sound
http://www.youtube.com/watch?v=lBQ_SnEg-58
http://www.youtube.com/watch?v=RuC6KaVfL9Q
http://www.youtube.com/watch?v=tbFtgwAebLg
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Old 01-25-2009, 11:39 PM   #23
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Quote:
Originally Posted by Stames_wiltz View Post
I have talked with my tuner about Headers and the ones he likes are APS, Fujitsubo and Tomei. APS has a new header out that shouldn't crack like the old one.
I've seen a few of the old APS ones crack...so hopefully the new one is better. Also, seen a Fujitsubo crack. The ones I'd recommend are Tomei or Cusco.

FWIW, here's mine. Tomei EL/uppipe, no cat, and HKS Carbon Ti:
http://www.youtube.com/watch?v=ZyrytevrAGA
http://www.youtube.com/watch?v=5Q06II7E8h4

Reflects the actual sound well enough...need to get some WOT footage soon. I love it.
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Old 01-26-2009, 01:13 AM   #24
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Quote:
Originally Posted by Davenow View Post
I have yet to see equals that spool as fast as unequals. They do make more power in the upper mid and top end, but I have yet to see one make the low end that an unequal does.

I don't know about quicker SPOOL, but they do seem to make more power more quickly. This comes from my tuner who sees it, I personally have not experienced it FOR MYSELF <-- disclaimer.
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Old 01-26-2009, 01:48 AM   #25
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Quote:
Originally Posted by keaniegenie View Post
that said, if you want quicker spool and equal length, twin scroll does the job.
.



to get true performance of twin scroll header you also need to have a twin scroll turbo to go with it..or its just a waste of money

case in point... a brand new set of perrin EL's to marry up with my borg warner s200

[IMG][/IMG]
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