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extra cash what to bolt on first. intake exaust

2K views 13 replies 8 participants last post by  oldfartracer 
#1 ·
i came across some extra cash...around $300. my motor is stock and i was wonder what would be the best first bolt on mod to the rex.
 
#2 ·
#3 ·
since your car is an 02', if not done already, i would spend the money on changing all of the fluids(brake, tranny, diff, etc) and replacing parts that may be worn before modding (brake pads, belts, spark plugs, drop in air filter and so on.) if you dont need to go that route and engine mods are what you want, you could save a little more for a catback exhaust then later get a d/p and a tune. some sway bars or short shifter/bushings would net you around $300 also.
 
#4 ·
What are your goals, In terms of power and stuff of that nature? If you are looking to gain a good bit of power your best bet is probably trying to pick up the cobb access port version 2 used ( can probably get it for like 300-400, its 700 new) and I think they say on the site it brings you up to about 260 hp at the crank with the stage 1 93 octane gas set up...Next best bet would be a down pipe/Catback exhaust (Which also getting it used would save you alot of money) and then you can use that accessport and go to stage 2 which I believe puts you at about 286 crank hp/286 tq at the crank. So essentially your car will be similar to a stock sti probably not quite as fast since they have the 2.5 liter engine which produces alot more torque. If you go catless you can pick up some extra power and it'll be a good bit louder only problem is passing emissions but there's always ways around that but it might cost a lil $$

In any rate as far as power mods are concerned that's your best bet, a intake is pretty much useless at least for now. Same thing goes with getting a aftermarket blow off valve my friend did that along with a intake on his 06 wrx and was like 2-3 psi lower then what he should have been, he put the stocker's back on and was running the correct boost levels. Another nice thing about it is if you want to make a lot higher numbers these are some mods you would have had to do later on down the road anyhow, and it should keep your craving for power satisfied for a little while as well.

Thats just my two cents tho, I am still a noobie myself.
 
#5 ·
+1 Make sure all of your basic maintenance is up to date and all of your wear parts are in good working order before you mod the fun stuff. I know it sucks, but that's the right way to do it. It's better than spending all of your extra cash impulsively on fun mods and later finding out that you need to replace something necessary to keep your car on the road and realizing you can't afford it without taking out a loan and putting yourself into debt.

Here's a link to reference if you're unsure what basic maintenance should be performed and when: Subaru maintenance schedules and new car break-in period

If everything's good to go, first figure out what kind of engine management you want to use and go from there (build gradually to stage 2, then beyond if your desire/funding allows). Suggestions for relatively inexpensive bolt-ons that you can do any time are: K&N replacement panel air filter, any brand of lightweight crank pulley, short shifter, aftermarket polyurethene bushings (all different kinds), most aesthetic mods, and intake silencer delete mod. Avoid blow off valves and aftermarket intakes until you are beyond stage 2 (power-wise).
 
#7 ·
my goals for the rex is that i would like to build it up to the cobb access port 16g map. these not much that you have to do it get to those power numbers. this remap will bring you around 346 hp. thats plenty of hp for me. im also going to replace the tranny soon. i was told by a local shop that i would need to get a new gear set if i wanted to do any heavy racing on it. he also said that the newer trannys from the 05-06 years were better. so what you be the smart move on that. get new gear sets or just a newer tranny.

one other thing im going to get the 2.5 sti short block put in. if i do the 16g cobb setup do u think ill run into issues being that ill have a hybird motor. or will i just produce more power.
i know this is a lot in one post,but im just trying to figure out whats the smart move for the rex. i dont want to make a bunch of wrong choices
 
#8 ·
Well if you are going to do the hybrid build, the AP wont cover any part of your EM. You could use it, but would HAVE to get a protune from some good tuner for it to even work properly. If you are going the hybrid route, I would just save the $300 unitl afterwards, or maybe see if you can find a used DP for the moment. You will get some gain, but no where near wha you would get with some type of tune or EM. Look at what Cobbs map notes call for the 16G (injecotrs, pump, IC, TBE) start pricing and saving for those parts. There isnt anything wrong with saving and waiting to get the right parts the first time.
 
#10 ·
In order to run the 16g map that cobb offers you need to run the exact mods that they list, FP16G turbo, STI TMIC, STi "Pink" 565cc fuel injectors, & turboback exhaust with a high flow catalytic converter using (or no cats) 93 octane. 346HP (+52%) / 286lb-ft (+32%) in addition to what it listed a catless up pipe.

So if you start to drift away from that list with the hybrid motor, perhaps wanting the big 16g, bigger injectors ect then your going to need a protune, so you might as well put your 300 towards a used catless down pipe for now it'll give you some more noise and some more power with out you having to spend money on a AP now and then no longer being able to use it down the road.
 
#12 ·
Yes. Either 91 Octane or 93 Octane gas is required with whichever Stage 2 map you choose. Read the map notes on Cobb's website: CobbTuning.com - Home Page

No. High-flow catalytic converters are not very restrictive at all. They might take away 1-5 horsepower from you (give or take), but it's really nothing major to worry about. The benefits of havng a catalytic converter are that it reduces the smell of noxious odors coming from the exhaust, it makes the exhaust sound level slightly quieter, and it makes it "slightly" more legal - and I use that term loosely.

No. Technically, any modified exhaust is probably illegal in most states. If you want to be sure, check with your local law enforcement agency. Even with a catalytic converter, your exhaust is still probably going to be illegal, although you might have a better chance of passing a "sniffer" test or visual test when you have your car inspected. Despite the fact that they're probably illegal, many WRX owners have aftermarket exhausts and have not experienced any negative ramifications from law enforcement. If you use common sense and don't mash the gas when you're around the police, you probably won't have any problems, but that's not guaranteed. If you're really worried about that, you could get a single or twin tip, stock-looking exhaust that's 3" and provides the benefits of an angled-exit, canister-type, obnoxious-looking, louder cat back. Many of the non-obnoxious looking cat backs still let you hear the nice boxer rumble too, if you're concerned about that.

One more thing - many WRX and STi owners keep their stock cat back exhausts because if we do get pulled over by the police and are required to "fix" the exhaust, the stock cat back can be swapped back onto the car and then the car can be taken in for an inspection. On the 02-07 models, the stock cat backs are not very restrictive, so they can normally be used with a Stage 2 tune without negative consequences. Switching cat backs is relatively simple also - 2 bolts and several exhaust hangers that just slide out of rubber bushings - several minutes on jack stands and you're done. Just something to think about.
 
#13 ·
Thanks for the quick and extensive answer. I was asking coz we don't have 93 octane anywhere in 200km. I think i'm gonna go with a turbo back turboxs. A good choice?
DP catless but with a hi flow cat for the exhaust. I heard thesound on youtube and it seems great but is it very loud in real?. Policia around here are not very plesant but i'm getting older so i'm getting a lower profile then all the little guys with civic.(I've got nothing against civic, some of those shit a freaking fast.) but i prefer the look and the comfort of my heated leather seats.
 
#14 ·
I ran a stock STI catback when I was stage 2. All you need to replace is the DP, that came from Cobb. Anything catless will be louder than a catted DP. You should also lose the uppipe cat for saftey.
As far as sound goes, this will very from TBE to TBE. Cobb, Greddy, Daddy make some of the quiter ones, HKS makes some nice mid level ones, TurboXS, Blitz and Invidia are some of loudest.
 
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