Can somebody run through the pros and cons of equal length headers vs unequal length?

http://forums.nasioc.com/forums/showthread.php?t=601219
Good info right there :) .

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

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.

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.

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.

sorry beer + typing = doesn't work right

sorry beer + typing = doesn't work right


been there :lol:

What provides the special sauce in ELHs? The smoother flow?

What provides the special sauce in ELHs? The smoother flow?


Its how the pulses line up in the pipe.

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.

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.

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.

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.

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??

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.

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.

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.