If you're poor , like me, u can go NA... a CAI, custom exhaust with 2.25'-2.5'' piping midpipe, headers, high-flo catalytic converter, cams, better clutch/flywheel, spring/struts from prodrive, and BANSUV's favorite rearswaybar.

or

-turbo the ej25 but u need to manage it VERY well with low boost otherwise u'll destroy your rod, gasket, tranny, etc etc....

-do a swap ej20 (wrx), ej257 (sti), ej22t (turbo legacy): there are merits to each

ej20 is getting to be a more common swappable engine for us now, so there are a number of places (that know what they are doing) that'll do it for you for a fair price. legal to do swap.

ej257 is rather expensive, i don't know much about this block, but i just know that it can't hold as much boost as the ej20 does. legal to do swap.

ej22t is what i'll be doing... as soon as I found out what the legality issues are with doing it. very reliable, safe power up to around 30 psi boost (according to zehpyr), can handle lots of boost, and the engine block is very cheap, especially used.

i just basically regurgitated everything i've read through these forums for about 6 months, do a search u'll probab find what u are lookin for. for more hardcore technical info tho, u should look on nasioc. i-club rules tho.

 

There's not a normally aspirated, mass-produced car in the world I'd rather own than an RS with those mods. (Funny- I DO now that I think of it ) Unfortuantely, if you stay NA, nothing is legal other than a catback exhaust.

Second favorite, after tires.

Not as hard as it used to be- I've figured out a shortcut for dealing with the engine management question. I will post all the details needed for this (in excruciating detail, not to worry) no later than the end of the month. The basic rule of thumb when boosting a stock RS motor is to run 50-60% of the boost your turbo would run if it were on an EJ20, i.e. TD04=8 psi max, GT25= 9 psi, etc. as long as you have control over fuel and spark.

This is the easiest, safest, cheapest (if you care about longevity) and only legal way of making your RS faster- with one catch. Running a legal engine means using a top mount, which means acquiring a WRX hood. I hope your RS isn't Blue Ridge Pearl, because if not, you can swap hoods with a WRX owner who has gone to a front mount. A full EJ20 swap goes for about $6000 now, including labor. Insurance won't know, and you aren't breaking any laws. Not to mention you will still have a wealth of tuning information at your fingertips since that engine is known backwords and forwards, unlike the EJ25t.

I just said that!

It can hold a lot more boost than people give it credit for. It's just that the larger displacement means you will get max air flow out of a given turbo without as much boost pressure. Boost doesn't kill engines, detonation (or physical malfunctions like oil starvation) does it. But just like with an RS-T, the extra 25% displacement means less boost than an EJ20, typically 25% less in the case of the EJ257 (imagine that).

The EJ22 is a good motor. WAAAYYYYY stronger block than 99% of us will ever need. Mark (aka Zephyr) falls into that other 1% however. Just remember that he knows Subaru engines like the back of his hand and has the budget not to flinch when his motors go boom. That 30 psi has a lot more to do with all of the other parts of his engine than with the bottom end. Anyways, if you go that route, you might as well go with a 2.35 liter motor- that's just an EJ22 with an EJ257 crank, custom rods and pistons (an off-the-shelf item if you know where to look and don't mind waiting to get them). Probably the strongest Subaru motor you can build short of lots of custom machining like sleeves and cryo-treating and all sorts of other expensive tricks. Anyways, the advantage to an EJ22 is that it can rev to almost 9k stock. The negative is that it's only 2.2 liters- and the stock EJ257 short block can safely rev past 8000 RPM.

 

If you want to go NA, the recipe is pretty simple. You definitely want cams. Cobb and TWE are the places to start there. You can also get valvetrain upgrades to support a higher redline if you like, which is a secondary benefit of cams. You'll want a full exhaust of course, 2.25" or 2.5" (I personally prefer 2.25 on my RS). A high-flow cat, and headers as well. I prefer the sound of Borlas over the extra couple of ponies that equal-length headers offer, because true equal-length ones make your car sound like an inline 4. And of course an intake. Cobb's is the best, but if you'd prefer to get 80% of the performance for 20% of the cost a PDM intake is only $55, and uses the stock filter. All that adds up to 205-215 hp at the crank, depending on your individual car. If you do all of your own work, that's around $1500 in parts, $1200 if you go with the less expensive intake and don't splurge on the catback.

 

if you can afford the cobb intake get it and most definately get borlas over equal length, the sounds is amazing and your not sacrificing any noticable performance

 

Great information BAN, I am in the same boat aswell. Currently I only have a Ganz and 20mm rear sway bar.

I was thinking about getting the Stromung Catback and prob. borla headers later on, my question is that whats the benifit of getting a 2.5" catback instead of a 2.25" catback and vice versa?

 

I have run a 2.5" Stromung dual tip catback, and a custom 2.25" setup with a Magnaflow. The 2.25" setup had better dyno numbers, but it also had a straighter midpipe and a better muffler design (louder too- a plus in my book ). But, given an equal design, as with a 2.25" Stromung vs. a 2.5" Stromung, the 2.25 would give you higher peak torque, while the 2.5 would give higher peak hp. Both make the car faster.

 

sweet thanks for the info, I guess I'm going with with the 2.5" catback, since I might do a XT engine swap later on.

 

If you that, you'll want a 3" exhaust actually. I forgot to mention the part about nothing for an NA build working the best for a turbo motor.