i just got unequal length headers installed and have changed nothing else, have a dyno sheet before and will have one after by next wednesday so i can show you

the exhaust note depends on the exhaust you already have and if you have a larger up-pipe, i've got an aftermarket up pipe then 3" mild steel all the way through with 1 racing cat and a magnaflow muffler and my car is fucking stupidly loud after the header install (was already loud previously), it is also quite raspy

i'll get stickered by the first cop who sits behind me, but otherwise it's lols

anyway for the gains you expect to see (if any) it is probably not worth the price tag, unless you're getting other work done (up-pipe) and decide to do headers whilst your there

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http://www.trapster.com - spot da haterz

Here's some real data on my (ex) MY06 STI I posted back in September...it may be useful for your decision making.....

"Here's some data for you to consider:

Figures are for (the same) MY06 STI....all on the MMS roller dyno and all using ECUTek III (Readings are all ATW):

MY06 STI + Stainless (Tomei) UEL headers: 197 KW + 409 NM

Above with UEL headers + CAI + silicon intake: 214 KW + 425 NM

Above with UEL headers, CAI, silicon + PW fuel surge setup: 217 KW + 430 NM

Above but minus headers and surge: 205 KW + 420 NM"

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No Subarus currently owned

It's not a 'run silly boost' thing. It was more that most go into a shop going 'oh noes my 2.5L is going to explode, give me a safe tune'. Same people then go and spend thousands more with extra add on mods. Same end goal could be achieved with a good tune to start with.

As others have said, you will get an improvement. Given that most people get headers and ceramic coat them, you are looking at $1k+ for maybe 10kW/10Nm. Then you have to ask, is that gain due to the header or the change in tune? I personally think that money would be better spent on other items that give bigger gains first (i.e. new turbo). Once those items are done, yes, have a look at headers to extract the most out of your setup.

Also consider what headers you are using, pipe size, runner size etc. Having these too big can be a major downside.

I personally went from stock headers to Tomei UEL. Loved the sound, but I didn't feel it was a bang for buck mod.

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[COLOR="Gray"]550Nm off a 2L... Just wish it was in the dak dak...[/COLOR]

I like candy

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06 sti

Headers are what you do when you have extracted all the other efficiency that can be easily had. Its a 1%er like an extra click of pre-load in your coilies or changing from bush to ball bearing in your turbo.

Same money can be spent elsewhere for larger gains in performance. If you have a significant modlist and are reaching its limits then by all means throw some headers on. Otherwise your just doing it for the sound.

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500+hp and helis on tap, eta - June 2025.

Going from stock to EL, there is a noticable difference in spool (quicker) if you dont mind not sounding like a typical WRX and sounding more like a Honda.

Whether the extra 200 - 300rpm of spool is "worth" it is up to you really.

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[B][COLOR=red]Jerk of the circle.[/COLOR][/B]

going from stock (adm)unequal length headers to equal length, there's a gain to be had. However you can port match oem as well to get gains.

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www.racewars.com.au

This thread did not exactly go as planned, it did go as expected though

Anyway, seems the general consensus is there is only a relatively small gain to be had for the $$. Figures bantered around are around 10kW and 10Nm peak increase)

However, peak figures only tell part of the story...Someone must have a before and after dyno (overlaid) for comparison?

My conclusion at this stage: wait for a twinscroll turbo upgrade and change headers then.

and sound like a Honda?

Yes wait till twinscroll. If you can get an oem twinscroll conversion, including spec c headers, you won't need to touch them.

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www.racewars.com.au