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Has anyone put a header and your STI, iam thinking about getting one and i wanted to know more about it once on the car , like to see how it performs?
 

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That STi belongs to Hummer. He's running the Gruppe-S unequal length header with the Jet Hot 2000 black thermal coating. You will 'feel' great gains with an aftermarket header if you just have the basic mods(intake, turbo back), but the gains from an aftermarket header are more substantial with an upgraded turbo and engine management. Basically what I'm saying is you will see more gains with an aftermarket header if you have gone with more significant upgrades.

Another thing to consider is what kind of power you're looking for. Generally, unequal length headers have great top end power gains, however, this design yields an inherent turbulance at the collector causing the 'lumpy' sounding idle. On the other hand, equal length headers are generally(pipe design will vary depending on manufacturer) great for low-mid gains. This design also smooths out the exhaust flow at the collecter heading into to the up-pipe which will also result in a smoother but buzzier sounding exhaust.

The Gruppe-S header($400) has been proven to gain as much as 13hp on regular WRX's. It's a well-crafted piece:



Another header is this one made by GP MOTO ($800)which is closely based on the Blitz header made for the STi in Japan. This is an equal length pipe design. Note that this header has an integrated up pipe, making purchasing an aftermarket up pipe unnecessary. This has been known to gain as much as 33hp on a regular WRX, but it's also DOUBLE the price of the Gruppe-S piece. It's a well-constructed piece as well:






hope this helps,


-STiLL
 

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my.subaru.com doesn't accept my VIN.

STiLLWILL said:
hope this helps,
-STiLL
Great info STiLL.

I lost a little torque when I put on the headers. I switched my muffler from the TXS RFL-TI to the TXS Magnaflow and it came back. DISCLAIMER: This was a butt dyno.

I think it is a great mod if you have a free flowing TBE.
 

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Anything to help fellow members. You guys have helped me TONS as well!


Thanks again,

-STiLL
 

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I've ran Maxim Works and GT SPec headers on STi's and the car responds well although without fuel tuning, you don't realize the full capabilities of them.
 

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STiLLWILL said:
That STi belongs to Hummer. He's running the Gruppe-S unequal length header with the Jet Hot 2000 black thermal coating. You will 'feel' great gains with an aftermarket header if you just have the basic mods(intake, turbo back), but the gains from an aftermarket header are more substantial with an upgraded turbo and engine management. Basically what I'm saying is you will see more gains with an aftermarket header if you have gone with more significant upgrades.

Another thing to consider is what kind of power you're looking for. Generally, unequal length headers have great top end power gains, however, this design yields an inherent turbulance at the collector causing the 'lumpy' sounding idle. On the other hand, equal length headers are generally(pipe design will vary depending on manufacturer) great for low-mid gains. This design also smooths out the exhaust flow at the collecter heading into to the up-pipe which will also result in a smoother but buzzier sounding exhaust.

The Gruppe-S header($400) has been proven to gain as much as 13hp on regular WRX's. It's a well-crafted piece:



Another header is this one made by GP MOTO ($800)which is closely based on the Blitz header made for the STi in Japan. This is an equal length pipe design. Note that this header has an integrated up pipe, making purchasing an aftermarket up pipe unnecessary. This has been known to gain as much as 33hp on a regular WRX, but it's also DOUBLE the price of the Gruppe-S piece. It's a well-constructed piece as well:






hope this helps,


-STiLL
is this true? does an unequal length header make more topend power than an equal length header? i always thought that equal length was better all over the powerband.
 

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Again, every manufacturer has its own formula pertaining to a certain 'type' of power gained, hence my generalizations. Each manufacturer has their own blueprint and intentions of power gains when creating their unique designs. This would explain why all the different brands of headers, both unequal and equal length, vary widely in terms of what rpm range yields their maximum efficiency.

Unequal length headers_generally_tend to make they're power at higher boost levels mainly due to their lower FLOW efficiency(substantially less low-mid gains) in reference to an equal length header. Equal length headers will tend to gain more power OVERALL, but most of that power gained will be within the low-mid range due to its HIGH flow efficiency(they make more power than an unequal length header at lower boost levels). Don't get me wrong, the equal length headers will also get you top end gains as well; that's only expected.

In my opinion, the equal length header would be ideal for best overall power gains, but remember thats only IMO. People have different goals for power gains and/or the type of power that is gained, not to mention different budgets. Equal length headers will always cost more. There are also people who like their Subarus to sound a certain way as well. Equal length headers change the exhaust sound characteristics considerably: more tinny/raspy and linear sound that seems to disguise the boxer engine's naturual Harley-esque sound. In contrast, the unequal length headers seem to only accentuate the classic Subaru boxer lumpiness.




-STiLL
 

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Just a comment. Anyone knows the good or the bad of the Borla headers for the STI? They are also offering a cat back system and claim it gives 8 hp/12/tq. The header supposedly gives 12 hp, but dont remember how much tq. This a total of 20 hp. Oh, by the way Borla claims they will not void the Subaru warranty and will give it to yoou in writting. Just a thought for those of you worried about the warranty issues. A bit of a powers sacrifice I must add...
 

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Engine Warning Light

blueballs said:
Hummer, you are the mod king on this forum!

That's quite a list...
My wife has said that the mod frenzy must stop until the Xmas presents are bought. The UTEC is the next big thing, but it looks like several months before it is released.
 

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THe Borla stuff I have seen for the WRX was very poor quality. In terms of equal length v. unequal length, the WRX responds well to both. THe equal length helps broaden the torque curve if done properly. Only equal length manifold I have seen that works better than many of the unequal length manifolds on the market is the Maxim Works. THat header allows some insane timing advance on the WRX and is good for over 20 whp. The only stock motor WRX to measure over 300 ft lbs of torque at the wheels on my dyno was done with a Maxim Works manifold. He laid down 316 whp and 301 ft lbs of torque. Car was running 12.1's before geting tuned.
 

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where can i take a look @ these maxim works?
url?
is coating the stock headers with jetthott or something similair advisable or no?
 

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Here is a pic of the Maxim Works header. Looks pretty sweet. Guru, what do you think of the JUN equal length header?
 

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The Jun header lokoks very nice. I have not tried it. They are very good shop and make excellent products but Maxim Works has much more header experience and have the reputation of being the supplier and developer of the headers for the Prodrive and WRC cars. Their quality is jaw dropping as is their price tag.
 

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Re: Japanese Model STi HID headlamps

gt spec gen II for the sti...they are beautiful and i got a 27 whp gain! 8)
 

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salisburyv said:
gt spec gen II for the sti...they are beautiful and i got a 27 whp gain! 8)
from just the headers?
wow!!
those are the ones that are only about $500 right?
did u use their uppipe or keep the stock one?
 
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