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EQUAL LENGTH HEADERS OR UNEQUAL?

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Old Oct 23, 2010 | 03:09 PM
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From: glenrothes,fife SCOTLAND!!!!!!
Default EQUAL LENGTH HEADERS OR UNEQUAL?

as the title states whats the best sort of headers?
whats the pros and cons of each and also the benefits i had harvey headers and up pipe on my last scooby with noticeable low rev spool and torque, they were standard ported.
what about ss?
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Old Oct 23, 2010 | 03:29 PM
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you lose the burble with equal lenght though,
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Old Oct 23, 2010 | 04:11 PM
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that the only diffrence between the two then
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Old Oct 23, 2010 | 04:36 PM
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Don't know if this piece from Tomei is correct, but at least it is an opinion:
http://www.tomei-p.co.jp/news/Report-EJ25-V1.html#C3.1
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Old Oct 23, 2010 | 04:39 PM
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From what i have been told:

unequal length headers = keep subaru burble + gain earlier spool

equal length headers = turn the subaru burble into a superbike style blat + gain better spool and slightly more power.

Equal length headers are supposed to be the ones to go for if you want maximum power gains but with the downside of losing the burble. Either will improve over standard system.
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Old Oct 23, 2010 | 06:05 PM
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my P1 with equal length headers has lost the burble (which i loved) but it now sounds literally like a racing car!! its amazing at high revs!!
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Old Oct 23, 2010 | 06:51 PM
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From: glenrothes,fife SCOTLAND!!!!!!
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hmm thats a hard one then eh everyone loves the scoob burble!! but equal length sould very tempting!! i may get them and just see if i like them if not could take them off lol
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Old Oct 24, 2010 | 10:59 AM
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Expensive to see if you like em lol
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Old Oct 24, 2010 | 04:30 PM
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Equal length Perrin Headers on mine. No burble, very addictive howl when on boost. Difficult to comment on torque as mine were fitted when a load of other bits went on. 321T harvey up pipe, 800cc Injectors etc. But I get 1Bar @ 2800Rpm.
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Old Oct 24, 2010 | 04:35 PM
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From: C+K MOTORS
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Equal on myn as well but i like the howl imho and defo give better torque as i first had my build on unequal and the difference on theses was alot and slightly better spool.
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Old Oct 24, 2010 | 08:02 PM
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There is very little difference in power output between equal length or unequal length tubular headers. The efficiency of the design will play a bigger factor in power output.
What is more important is getting a set of tubular headers that are reliable and capable of producing good power. Lots of header sets for sale on e-Bay and here that are cheap are either poorly designed, made of thin steel, poor quality welding or all three.
Whatever you do go for a set of quality tubular headers with proven performance.
Chances are that if your turbo is not capable of 400 bhp or close to you will be better with ported headers with matched uppipe because generally tublar headers will slug spool.
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