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Old 04-28-2009, 01:57 PM   #1
olsen726
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2.5i???

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hey guys, i have been planning on boosting my car since pretty much day one. I have done countless hours of research, and think i am finally ready to start the project. i plan to do this in two stages..

.first stage. turbo kit installed on current block 5-8 ponds of boost
.second stage. swap in built block, new clutch...turn up boost.

.goals.

around 350 hp give or take
daily driver, i want it as reliable as possible

now for the build

.engine.

let me know if there is anything that would be better, or that i am missing this is the part of the build that i have the least experience with, and am most concerned about.

forged pistons
sti rods*

sti oil pump
dual springs/ titanium retainers*
delta cams*
acl race bearings

.fuel system.

walboro fuel pump*
modded wrx injectors*

.turbo/exhaust.

Precision t3/t04e 60trim*
modded 3" ebay turboback*
borla headers*
custom up pipe*
custom dp extension*
Greddy Type-S bov*
ebay fmic*
custom intake
Tail 44mm EWG*
oil drain/feed lines*


.e/m.

Cobb accassport*

.miscellaneous.
random hoses

soo... i want everyone to nitpick at anything you see in my build that might be a problem, and let me know if there is anything i may have missed. and i do not want to hear a single word about just selling the car, or just doing a swap, i know that normally is the cheaper route but it will not be any cheaper in this case.
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Last edited by olsen726; 02-18-2011 at 09:29 AM.
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Old 04-28-2009, 02:26 PM   #2
funky monk
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ibbuyawrx

good luck with your money pit.
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Old 04-28-2009, 02:35 PM   #3
Urgaynknowit
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well, im gonna say what every one else is thinking, buy a wrx..... save ur self a **** load of work

but, since ur doing thisi give u props,my friend just did it, only he threw a built 2.6 into his rs, and it whips, props for doing things outside of the box, but its not gonna be easy.
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Old 04-28-2009, 02:47 PM   #4
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Quote:
Originally Posted by funky monk View Post
ibbuyawrx

good luck with your money pit.
you're a dumbass....go troll somewhere else

and i am having very good luck with my money pit....you go have fun with your 130 hp in a 3000 lb car....and let the real enthusiasts talk about building their car and putting in the work....


Quote:
Originally Posted by olsen726 View Post
hey guys, i have been planning on boosting my car since pretty much day one. I have done countless hours of research, and think i am finally ready to start purchasing the parts to build my spare block. this will be my first full engine build but not my first engine or turbo swap...so here are the details that i have worked out, and some of my questions. i want as much constructive criticism as i can get, that way i can have most of the kinks worked out before hand and the project will go as smoothly as possible.

.main questions.

i am going to keep my non-turbo xmember, i know I'm going to be using a custom up pipe, but do i need a custom downpipe as well?

depends on the location of the turbo...if you put it in stock wrx location then u can use wrx downpipe...however the stock wrx location sucks on an RS....so you're best bet is to find a location that fits nicely and have both the up and dp made...check out the older ludespeed, avo, etc kits for ideas

I plan to have an e85 map, and have no idea what size injectors I'm going to need?

e85 takes a lot of injector...better go with 800CC...just use the wrx blues modded....cheap and will work with your stock everything (just need some o-rings - call rallitek)

should i get an external wastegate?

definitely better but not needed.....if you have the cash for it then definitely yes

now for the build

.engine.

let me know if there is anything that would be better, or that i am missing this is the part of the build that i have the least experience with, and am most concerned about.

sti pistons
sti rods
sti rings
sti oil pump
ported heads
duel springs/ titanium retainers
delta cams
acl race bearings

what headgaskets will u be using....sti will give u 8.7:1 CR, cometic will give u around 8.2-8.3

.fuel system.

walboro fuel pump
bigger injectors (what size?)

.turbo/exhaust.

tdo5h 18g*
3" ebay turboback*
borla headers*
custom up pipe
w1 bov*
ebay fmic*
custom intake


.e/m.

right now i have an accessport, and am hoping i can have my tuner tune this setup, and save the maps onto my accessport for me.

im not very familier with the 2.5i EM.....but make sure stock ecu is capable of handling boost with accesport flash.....

accassport*

.miscalleanous.
random hoses

soo... i want everyone to nitpick at anything you see in my build that might be a problem, and let me know if there is anything i may have missed. and i do not want to hear a single word about just selling the car, or just doing a swap, i know that normally is the cheaper route but it will not be any cheaper in this case.
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Old 04-28-2009, 02:50 PM   #5
olsen726
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i have very good reason for not selling my car,and the main difference in building an rst apposed to a swap is just building the motor and engine management. and i already have an em that will hopefully work, i also have a spare block at home. and if i was to buy a wrx it would just become my moneypit rather than this car.

Last edited by olsen726; 04-28-2009 at 02:56 PM.
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Old 04-28-2009, 02:53 PM   #6
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thanks jeff, how expensive are the cometic compared to stock?

and do you know anywhere that sells a bellmouth flange? because if i go with a custom dp i might as well use one on my dp
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Old 04-28-2009, 02:53 PM   #7
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at least you know it's a money pit. Just stating a fact.

And I would assume the turbo engine blocks are different from the NA ones. You can change all the internals, but how will the block hold up? How much boost do you plan on running?
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Old 04-28-2009, 02:59 PM   #8
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well I'm pretty sure these blocks can take up to around 400hp. and i don't really plan on going over maybe 300, so i think the block will hold up fine for what i'm doing.

Last edited by olsen726; 04-28-2009 at 03:12 PM.
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Old 04-28-2009, 03:28 PM   #9
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Nothing wrong with wanting an RS-T. My Outback has a turbo'ed 2.5L in it. Just know going into it that people can put less money into a WRX and be faster than you, but you will always have the advantage of being "different."
Why are you staying with the N/A x-member. You wont have to go the custom exhaust route if you just swap to the WRX or older Legacy turbo x-member.
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Old 04-28-2009, 04:12 PM   #10
olsen726
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i just got a new swaybar, and don't wanna have to get a different one and i have an exhaust guy that can fab me up an uppipe for less than the cost of a new xmember, uppipe, and swaybar...and now jeff really has me thinking about a different mount for the turbo
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Old 04-28-2009, 04:23 PM   #11
Jeff54
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Quote:
Originally Posted by impreza_GC8 View Post
Nothing wrong with wanting an RS-T. My Outback has a turbo'ed 2.5L in it. Just know going into it that people can put less money into a WRX and be faster than you, but you will always have the advantage of being "different."
Why are you staying with the N/A x-member. You wont have to go the custom exhaust route if you just swap to the WRX or older Legacy turbo x-member.
cause the wrx stuff sucks on an ej251....first off you cant run an inlet under the intake manifold easily since the manifold sits lower than the turbo ones, secondly the power steering lines go right where the turbo sits....i mean it works but it's definitely not ideal.....

and yeah the block will hold 400 whp fine....but get some ARP headstuds to help the HG out a little bit if you're going to be making numbers close to that high....

and i really beg to differ on the "more money into wrx and be faster than you"....when you factor in the difference between the two cars....

my car at 3500$ invested (+ 10K for the car) was stomping stage 2 stis....with a used hydra, rebuilt ej255 shortblock, mhi 18G and everything else cheap/ebay/no name parts......

now i have more in it...but i'll be going bigger turbo hopefully this summer and shooting for 400+ awhp....

just need to figure out what to do about the tranny....
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Old 04-28-2009, 04:26 PM   #12
Jeff54
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Quote:
Originally Posted by olsen726 View Post
i just got a new swaybar, and don't wanna have to get a different one and i have an exhaust guy that can fab me up an uppipe for less than the cost of a new xmember, uppipe, and swaybar...and now jeff really has me thinking about a different mount for the turbo
yeah a rotated mount will be much better.....more clearance for everything...and also allows you to go to a giant turbo in the future.....

also if you're gonna be going to be going the custom up/dp route dont mess around with subaru specific turbos (flanges).....go t3/t4 flanges and open up your options for cheap turbos
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Old 04-28-2009, 09:11 PM   #13
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thanks for all the help jeff. so your running an 18G on your setup too?
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Old 04-29-2009, 04:05 PM   #14
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Originally Posted by olsen726 View Post
thanks for all the help jeff. so your running an 18G on your setup too?
yeah but not for long...too small
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Old 05-27-2009, 03:11 AM   #15
olsen726
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i just got some pistons and rods from an 06 wrx, i know they have higher compression than the sti pistons. does anyone know if these are gonna be able to push 300whp reliably? i'm still going to search it, just wondering if anyone knows what these are capable of off the top of their head?

Last edited by olsen726; 05-27-2009 at 03:19 AM.
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Old 06-07-2009, 12:47 PM   #16
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The AP will prolly cover this, but the most important lesson I learned on my 2.5i was that while tuning, you need to make sure that EVERY table in the map is scrutinized and set up for boost. I had everything perfect except for once tiny little 6 cell table in Tip-In, and that one little table was able to stop all Tip-In flow above 0 psi and effectively make my car impossible to drive faster than 30-40 mph. The ECU on your car doesn't have the foggiest idea of what positive pressure is, so it will either ignore it or think it's gone schizo and do something crazy unless you tune it completely inside and out.

As for the pistons, 06 WRXs are set at 8.9:1 CR, right? IIRC 9:1 is good for like 15-18 psi so that likely leaves you a bit under 300 at that CR. Maybe they can do more than that? I don't know, that's just something I remember reading last year somewhere on here
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Old 06-07-2009, 02:08 PM   #17
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Quote:
Originally Posted by funky monk View Post
And I would assume the turbo engine blocks are different from the NA ones. You can change all the internals, but how will the block hold up? How much boost do you plan on running?
Yes, the blocks are different. The WRX and STI are semi-closed, the 2.5i is open deck. The heads on the WRX and STI flow better than the 2.5i and have cam profiles built for boost as well as the proper fittings for oil/coolant.

Quote:
Originally Posted by olsen726 View Post
well I'm pretty sure these blocks can take up to around 400hp. and i don't really plan on going over maybe 300, so i think the block will hold up fine for what i'm doing.
Stock STI blocks have a tough time holding up to 400whp.

Quote:
Originally Posted by impreza_GC8 View Post
Just know going into it that people can put less money into a WRX and be faster than you, but you will always have the advantage of being "different."
Not an advantage, there is much less support as far as products and knowledge go for those who are "different."

Quote:
Originally Posted by Jeff54 View Post
my car at 3500$ invested (+ 10K for the car) was stomping stage 2 stis....with a used hydra, rebuilt ej255 shortblock, mhi 18G and everything else cheap/ebay/no name parts......
I have about $500 more invested than you do but ended up with an ej257, 6speed and brembos and name-brand parts.

Quote:
Originally Posted by Spudchucker View Post
The AP will prolly cover this, but the most important lesson I learned on my 2.5i was that while tuning, you need to make sure that EVERY table in the map is scrutinized and set up for boost. I had everything perfect except for once tiny little 6 cell table in Tip-In, and that one little table was able to stop all Tip-In flow above 0 psi and effectively make my car impossible to drive faster than 30-40 mph. The ECU on your car doesn't have the foggiest idea of what positive pressure is, so it will either ignore it or think it's gone schizo and do something crazy unless you tune it completely inside and out.
Exactly, many of your sensors (eg. fuel tank pressure sensor) have no idea what boost is and it's quite the battle to set up a NA car for boost without a standalone or extensive work in opensource.
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Old 06-07-2009, 02:40 PM   #18
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wouldn't it have been easier to just buy the STI block for 1600 bucks new and then bolt your heads when your ready instead of block..(rs) and STI internals...I mean unless you don't want to do more than 350 to the wheels then yeah go for it and good luck but sti blcok would have been a bit easier on you...but the man likes a challenge so I like that..I'll be doing pistons and rods only when my RS block blows up from SCing
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Old 06-07-2009, 03:42 PM   #19
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thought about doing an sti sb, but i kinda wanna build my own. and i think I'm just gonna go with some aftermarket pistons, rather than hoping the wrx ones will hold.
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Old 10-09-2009, 03:07 PM   #20
olsen726
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its been awhile since i posted on here. i lost my job so progress came to a screeching halt on the project. but i haven't abandoned it. i went ahead and bought me a used turbo. its the turbo from the Ultimate Racing Rotated T3/T04E Kit. this beast should be more than capable of pushing the numbers i am hoping for. I also have a buddy that is going to possibly selling me a set of modded wrx injectors and ewg. But with big turbos comes problems. i have realized that the cute little fmic i have wont be big enough for this application. so i think what i am going to do is go ahead and either find a used core, or go buy one off of ebay.
I am currently taking some metal fabrication classes at my college, and either for my final project, or just something on the side i plan to make my uppipe, downpipe, and hopefully run some intercooler piping as well. this will save me a pretty big chunk of money on the project, and will allow me to run my exhaust/ ic piping however i want.

I still haven't made any progress on building my block. i think I'm gonna fab everything up, and then decide what i want to do as far as the motor goes when i have everything else ready to go. i know the turbo is capable of over 400 whp. so i might go ahead and find a blown ej257 short block, and rebuild that with some forged pistons and all that fancy stuff. or maybe see how much it would be to get my spare block sleeved and whatnot to hold the extra power... time will tell. if anyone with a good amount of engine knowledge has anything to say about the motor plans feel free to chime in. the only thing i know as of now is i am going to be running my heads, and forged internals. i want to use my extra N/A block, but am not sure how wise of a decision that is with this turbo.

also, I'm gonna be headed down to PIR (local track) tonight to see what she runs N/A with some head work. will be sure to post the results when i get home


sorry for the huge post, just figured you guys could use an update, and i could use whatever feedback you guys have.

and here are a couple pics of the this is taking place on



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Old 10-10-2009, 03:38 AM   #21
olsen726
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just got back from the ole track. ran a 15.3
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Old 10-10-2009, 05:14 AM   #22
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thats about what i was running on the tracks, I hit 15.3 once, the rest were about 15.4's or .5's. Good luck on the build, I plan on turboing mine, i'm waiting on some sti internals, I have the twin cam cylinder heads at home but i dont know if i'll use them yet, an 06 wrx crossmember, I just cant find an intake manifold yet.
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Old 10-10-2009, 02:33 PM   #23
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good luck sir, hope it all works out. when i can afford another car ill do the same to my baby, but until then its going to be a n/a demon
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Old 10-10-2009, 04:45 PM   #24
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If you want to run a wrx down pipe in the stock location, build off of the down pipe and turbo. Don't just make an uppipe and hope it fits with the exhaust, downpipe and turbo. just my $.02
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Old 10-10-2009, 11:36 PM   #25
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Save yourself the grief and wait for this. http://www.raptorsc.com.au/kits.php?id=49

Having turbo'ed my 97 and several other cars in the past 10 years of getting into modifying Subies I'll tell you this, no matter how much research, time and effort you put into your build, something is going to go wrong. The factory built that engine specifically to run well naturally aspirated, not with forced induction.

It is your money and you are free to do with it what you please, but you are going to be 1 of a million people who have tried this since 1993, who ended up having more issues than it is worth. A motor swap will end up being cheaper, or trying that supercharger kit will get you "safe" 230 hp.

Good luck to you, it's going to be an uphill battle.
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