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was talking to an ex drag racer, he recommended i got for tuned length extractors- sayed with a 4 cylinder u shud have 4 pipes cumin out and if they r all the same length the airflow, power and to some extent economy will improve. but i can only c 2 pipes cumin out the engine.

LOL... do u have a drag car motor in your car? What he told you is probably right on a drag car... wont do anything but cost u a lot of money on your car.

BTW... Milla i just sent u a PM on another subject.

Dave

In my opinion even length headers aren't as good as everyone makes them out to be. Particularly in a Subaru.

On an EA engine you essentially have performance headers from the factory. The exhaust ports are siamesed, giving one port per head and the stock pipes are only a litttle smaller than this port. This gives relatively good flow while maintaining some back pressure.

For the exhaust you intend on fitting in your "mods to come" part of your sig, you're best off using factory headers and 2 1/4" pipe from the headers back.

Whether or not any of this is worth it on an EA82 of any form is another thing entirely.

Same length headers on my Ej22 made the car sound like a dirt bike... performance seamed un-changed.

Dave

Am I missing something?
You can't have 4 pipes comming out of 2 exhaust ports.


Most conventional 4cyl motors have one per cylinder and alot of them have pretty basic manifolds which only terminate to 2 or even one exhaust pipe. This is improved by a good set of extractors with an individual pipe for each port on the head. Your friend probably didn't realise that your EA82 boxer motor only has 2 exhaust ports (one in each head). The stock extractors are about as good as you can get really. Possibly can be improved by deleting the CAT (if yours has one) but this really has negligable performance gain but considerable environmental damage.

Yeah i felt creative last year and made some extractors for my L

I got the plans off an aeroplane site,.. they are designed so that the entire contents of one cyclinder fill one exhaust pipe. So i made it so the contents of 2 cylinders (0.9lt) filled that pipe and made the two 0.9 lt pipes merge in a Y shape. They actually ended up being very similar sizes to the stock headers. (except they were equal length) [PIC attached]

They did very little for power (removing the cat made the biggest power increase but i dont suggest you do that)

The biggest difference was the change in noise, it lost the boxer rumble and didnt sound much like a normal 4 cyl either. More like a race car. (with lost of backfire)

I didnt leave them on for long, i went back to stock headers with 2.25 from cat back and a sports muffer,.. you wont get much better than that.


Gannon

cheers for that guys, perfect replies.
will just go with the catback-hotdog-2"1/4 pipe.

ive got headers on my car and i reakon they made a difference hey it goes better and its better on fuel buy about 80km per tank.....

i had a massive set on my car .. 2.5" from each port into 2.5" pipe, it lost a heap of bottom end and didn't real gain alot of top end. made a great noise though.

Where can you get performance headers for the EA engines and how much would they set me back?

Any exhaust shop could make you some , allthough unless you have a problem with yours now , the cost will not be worth the result .the Subi exhaust unlike most cars does not have an exhaust manifold as they allready have and exhaust similar to extractors.

Mike.