Hey everyone. I have a possibly stupid question about the exhaust manifolds on the EJ20Ts that is going to make me sound like a complete newb, but still I must ask. As some of you know, I own a 95 WRX wagon and a 02 WRX wagon. Well, I just had an epiphany and was wondering if the aftermarket exhaust manifolds offered for the 02 WRX would also fit the 95 WRX? Maybe I'm being nieve about this, but I figured that an EJ20T is an EJ20T no matter what the year, but I just wanted to know since I didn't really get far into modding my 02. If anyone can shed some light on this, I'd greatly appreciate it and so would my pocketbook.

 

Patrick

I would say yes. The thing that may differ is the up-pipe and how it mounts to the turbo. From an FAQ on nasioc:

Q: "I'm doing an EJ20 swap, which exhaust should I use?"

A: Until proven otherwise, the exhaust from a standard WRX from 1993-2004 has remained relatively unchanged. This means that if you are performing a swap from an Impreza chassis to an Impreza chassis, you can use any complete WRX exhaust. If you are swapping from an Impreza chassis to a Legacy chassis, then the exhaust must be lengthened to accomodate the longer chassis.

 

If you are doing a piece-meal exhaust, there are four types of downpipes available from any of the EJ20 equipped cars: the twin-turbo downpipe, a la GTB; the twin-scroll downpipe, a la STi Ver. VIII; the IHI flanged downpipe from a pre-MY01 JDM vehicle or post-MY01 non-JDM vehicle, a la USDM WRX or STi Ver. VI; or finally the IHI flanged downpipe from a post-MY01 JDM vehicle; a la STi Ver VII. The twin-turbo downpipe is only going to work in a RHD car, so this will almost never be used. The twin-scroll downpipe can only be used with an IHI twin-scroll turbo, so this will only be used with some STi Ver. VIII vehicles. The pre-MY01 JDM downpipe is the most common downpipe used with EJ20 vehicles. The post-MY01 JDM downpipe was introduced with the GG/GD chassis and is a few inches shorter than the pre-MY01 downpipe.

 

If you choose the pre-MY01, then you must mate it with a similar system. It can be mix-matched as long as it is not matched with a post-MY01 JDM system; this includes using cat-backs designed to work with the EJ25 engines. If you choose the post-MY01, then you must mate it with what is commonly referred to as a "JDM cat-back". The flange at the axle was rotated on the GG/GD chassis so the mid-pipe and the axle-back must be from the same chassis generation.

Hey, I really really appreciate the input. That is what I needed to know.

 

Patrick