ClubWRX Forum banner

241 - 244 of 244 Posts

20 Posts
Greetings and Happy Holidays,

Very new here and to the Subaru world. I have owned a modded, 300 whp Mazdaspeed3 for the past 11 years that I still have, but just picked up a low-mileage '17 WRX Premium to daily drive. I have been reading through lots of these threads about mods and have gotten a good idea of what it takes to make a safe Stage 2, 310-330 whp in this car on 93 octane, but the ambigiuity for me sorta lies within "what order" should I smartly do these mods in. That seems to be what this thread is for. As with most people, I don't have the funds to go all out now, but probably willing to spend $500-1,000 at a pop every so often to get to my end goal. I am not including styling/engine dress up mods in this because that is mostly subjective and straight forward.

The suspension side of things seems straight forward and not much different than any other car I have modded. Springs, dampners, swaybars, endlinks and bushings. Any gotchas with this car's suspension? Priorities/concerns/avoids? Is a strut brace and pitch-stop mount worth it?

Moving on to the transmission, I plan on working on the shifter, whether it be with Perrin's products or a whole new assembly like the Boomba. It will probably be one of the first things I do since it won't require a tune and I can get my money's worth out of it every day even at stock power levels. Any suggestions on going in one direction or the other?

As far as engine mods go, I don't want to have to do things twice or spend more money later on because I was near-sighted and wanted instant gratification. Of course, I have never made that mistake before. ;) As with some of my cars in the past, I have installed a mod and later thought, "I should have just spent a little more and installed the other mod I wanted to install while I was in the same area". There are just certain areas of an engine bay that are a pain in the nuts to get to and it helps to group mods, when able, in order of installation convenience though, obviously some of those will need a tune. I know some tuners out there like MAP offer OTS tunes when you buy their Stage packages, but once you start mixing part manufacturers you get into a grey area. I would rather not spend ginormous amounts of money on the dyno. I do have Cobb AP experience since it is what I have used for almost a decade now on my Speed3 with good results street tuning, but it appears to me the Soobies are a little more finicky with the quality of the tune.

So for the people who have done this many times before, in a perfect world, what would you do or what did you do that you would have done differently knowing what you know now? Why did you pick the Grimmspeed intake or EBC over the Perrin models, ect.?

Lots of holiday sales right now with the online vendors, so I am ready to get started. What I am thinking of doing to start things off are the Perrin rear shifter bushing, shifter stop and solid shifter bushing, along with a new shift knob. I'd also like to do their strut tower brace, 22mm rear sway bar and front/rear poly endlinks and finally their pitch-stop mount.

Thanks for the inputs!

The first item a purchased and installed on my 2017 WRX was a Kartboy Cable Shift Arm W/Bearing (P/N KAB KB-20-WRX) for about $112.00. It reduced the shifter throw by about 50% - well worth it. Then I went to a K&N Air Filter P/N 33-2304.
Enjoy your new ride.

6 Posts
3) Engine Management: Opensource reflash, Cobb accessport, or professional tune. Increases your boost safely with fueling and timing adjustments etc. etc. and allows you to run a DP safely. Also very beneficial without a DP (stage I).
thanks for the info
i live in Qatar, having WRX i spoke to COBB who informed that they support ADM & USDM can anyone recommend which one would work in this part of the world? and if there is a way to know what DM is my car :)

41 Posts
This seems to be the most commonly asked question. For those who want to research and understand how everything actually works and what all the pluses and minuses are, these questions have all been addressed and a great deal of information is available by searching. Researching each individual component you put on your car is the recommended approach. Beyond that, you must make the final decision and take responsibility for everything you do to your car. This thread is intended to simply summarize the most commonly recommended options and to provide a brief explanation for the reasons.

For the most part, the answer is pretty much the same whoever you ask when discussing 02-07 WRXs and STis. I am not sure what is up with later years, maybe someone else can add any differences.

1) Uppipe: Only required for '02-'05 WRX (no cat in other years/models stock). This is to replace a cat that we have all seen pictures of becoming detached and entering the turbo (bad). Do this first because everything else increases that chance. Very generally 10HP+ and 500 RPM sooner spool is the bonus. PITA to install but cheap to buy.

Attn '02-'05 WRX Owners: The Importance of the Uppipe Mod

Uppipe, Downpipe, Muffler INSTALL GUIDE!

2) Downpipe (bellmouth or divorced wastegate): All years/models. Replaces two restrictive cats. A highflow cat is recommended on 2.5l models to restrict the possibility of boost creep and is my preference on 2.0l. MUST be tuned or used with a stage II map (except '02-'03 some say but do it anyway). Gains are substantial with a tune. Read on boost creep if you have a 2.5l.

Exhaust FAQ

3) Engine Management: Opensource reflash, Cobb accessport, or professional tune. Increases your boost safely with fueling and timing adjustments etc. etc. and allows you to run a DP safely. Also very beneficial without a DP (stage I).

4) Catback: This is only for your sound preference. Gains are minimal for the cost. Don't fall into the trap of getting something too loud unless you are sure you like that. Match to the DP for connection - options are 3" flat flange or ~2.5" doughnut (stock)

5) Intercooler hoses: Not that often recommended here but is a great mod for the $. Better flow and maybe reduced temps. - gain is 5hp or 8hp according to the famous author depending where you read.

-1) MBC - Only run these because your tuner recommended. Not a safe way to up boost except very marginally on '02-'03WRX and maybe '04-'05 STi without EM and correct tuning. Engine management is a FAR better option to get more boost and HP on all models. Does not account for extra fueling etc. needed. Issues without tuning include partial throttle full boost, causing bad lean conditions and horrible drivability.

-2) Intake - not necessary yet. May skew your MAF causing you to run lean. If you want one, make sure that it is certified to not mess up your MAF scaling and make sure no one has run into problems or better yet get it tuned. May be a consideration for stage 2 STi.

-3) BOV or Blow off valve: just a noisemaker and not really ideal for your car.

-4) Turbo Timer: Not needed. The turbo is water cooled even after shut-down.

At this point, your biggest gain/$ will be to do your turbo and supporting mods (intercooler, fuel pump, injectors, tune). The most common standard recommendations are 16G EVOIII for 2.0l or 8cm 18g for 2.5l WRX (you are really slacking if you don't research this). Consider an even larger turbo to upgrade the STi.

A variety of other things can be done still though to improve flow, cool the intake charge etc. However, manual boost controllers, intakes and Blow foo valves are not on the list for reasons.

6) Intercooler - STi is already a little better than WRX and can be used to upgrade WRX - small gain little bit cooler charge. High quality big TMIC gives less pressure drop (at least 2 PSI), faster response, less chance of det. and can be tuned for ~15-20hp. Supporting mod for turbo upgrade.

This is pretty much of the top of my head so if you see an error I will correct it.
So helpful thank you for taking the time ?

14 Posts
Mostly good advice from others there... if you want to waste money on pixie-landing a car....maybe just to 'own one'.
or feel part of a 'community'. Good drivers generally don't need that but people needing to find support for their
extravagant and ill chosen 'upgrades' often do so. There's a point in car clubs when they actually facilitate getting
parts but my experience is they want "everything for nothing " and sell to new members at inflated prices. Like a
football deflating through being kicked so often, the need to be re-inflated with the hot air from similarly addicted

My suggestion...leave it stock standard and focus on suspension brakes and tyres. Avoid coil-overs...especially
the after-market Chinese rubbish sold for Suburu); if buying shocks buy only properly selected Bilsteins and
check coil heights for possible replacements. The harder you make suspension the more stress on associated

Stick to original rubber suspension bushes, maintain alignment, use best tyres you can afford without excessive width,
maintain brakes with rebuild of callipers every two years, complete replacement of clutch and brake fluid every
year. Maintain 'perfection' in steering and alignment.

Check all driveline oils every six months. That will give you a car great to drive, maintaining value...or you can
spend the money in reducing its value and market interest, requiring increasing maintenance and possibly
catastrophic failure or catastrophic incidents.
241 - 244 of 244 Posts