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Old 04-15-2010, 06:19 AM   #1
LilSubie
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Arrow 08 Wrx 350whp?

Ok, so I'm in the military and my car is in storage for effing ever (3 years!) but when I get back...Deployment money + 08 WRX = Fun! I need some help though. This car is my daily driver so I don't want to go crazy but I want to be able to have some fun every now and then. I want my WHP to be at 350 and TQ close to the same. Below is my current set up (I plan on keeping the SPT cat back and adding a cut out QTP at the DP so no exhaust recommendations please).
What I am asking for is recommendations of mods that will get me to my desired HP and TQ range SAFELY. When I say safely I mean that when recommending upgrades please make sure that all the upgrades (get a bigger turbo etc.) are recommended that you include ALL supporting mods needed to be reliable.
I have some idea's of what I think I need but it is allways nice to get the ideas of others. Thanks for the help.

Current mods:
-Stromung DP
-SPT CBE
-GFB BPV
-KNN drop in air filter
-Perrin LW crank pully
-Cobb AP with pro tune
-boost controller to stabilize boost (had issues with in experienced tuners who claimed they knew Subaru's well. *wouldn't recommend Atlantic Motorsports*)<-- Evo guys
- Kart boy short shifter

Current set up gives me 240 whp and 313 TQ

Again, I have some ideas but would prefer to hear yours and please, if you are going to respond, make sure you know what you are talking about from experience. I really don't want some stupid response that is generalized "get a bigger turbo and FMIC". Specific recommendations please. Thanks all.
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Old 04-15-2010, 07:22 AM   #2
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The only way you'll see over 300 is with a new turbo. If you get a vf52 you can get 300 with nothing else. If you get a vf52 fuel pump injectors larger ic then u can hit over 300 and alot more with e85. But if you really really want 350+ you will have to go with a bigger turbo and will have to use a fmic as there army many turbos that will fit otherwise. As far as what turbo? That I don't know, others can suggest turbos I'm not that up to date with turbos.

I do know that 09 guys with full TBE, larger TMIC, upgraded fuelpump and injectors and Cai are getting huge numbers with e85 tunes. Search a little on here and you cAn find alot of info.

Sadly our little tdo4 will never see those numbers
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Old 04-15-2010, 08:47 AM   #3
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Well I definately need a larger turbo. This much is obvious. I really don't want to go with the 09 set up, I want something slightly larger than what the STI uses.
Once again i want to re-iterate what I said before. Please don't post unless you have experience in this and know ALL supporting mods needed. Specifics Specifics.
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Old 04-15-2010, 08:58 AM   #4
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TD05-20G 8cm^2 is how I'll be getting to those numbers.

You can wait on the Blouch stock fitment ones (all 20G's will be TD06's) which have not been set a date or final price yet. Also AVO has the 450 which fits, but is not by any means cheap.

I'm going 02-07 fitment by using the TurboXS FMIC.

You'll also need a fuel pump (AVO is drop in but huge $ and Walboro is not a direct easy fit).

Finally of course you'll need some injectors to feed the new power. I'll be going with Witchhunter 820cc's personally. 750cc could do it but will be higher than my tuner likes to see IDC's at when tuning, and I trust his word.

Find a good tuner and you should be fine.

One more thing I'll be needing is a new clutch, 31K on my stocker and big numbers I'll look to the ACT HDSS.

My project should be done in 30-60 days (using all cash to stay financially responsible).
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Old 04-15-2010, 09:38 AM   #5
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Let me know how that goes, I'm curious to see your results. Now I have heard some rumors about the transmissions on our models having problems with holding up under high TQ. Any one else heard or experienced this?
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Old 04-15-2010, 10:09 AM   #6
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http://surgeline.cobbtuning.com/dyno/index.php
Richard Zielinski -2010 STI

And you can page through and find others... for 350/350 you should go for a 20g / AVO380 / dom2.5 / etc

Supporting mods: Fuel pump, injectors, fmic, downpipe

Suggested: Intake & turbo inlet

Pretty simple


As far as the transmission goes- the older 5 speeds definitely had issues- but the rumor is that the new one have the LGT gears in them and are a good bit stronger... I haven't seen a broken one yet /shrug
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Old 04-15-2010, 10:52 AM   #7
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AVO turbos have performed poorly in use with our engines in the legacys and WRX's.

Our trannys are stronger than the 07 WRX trans so your HP numbers should be safe as long as you drive and do things sensible, any trans will break if you sit there clutch dumping at 4k rpm.

you could go front mount and use any old style 20g prolly 800cc injectors, and good tune.

any old 18g and run e85 and probably 1200+cc injs (consult with tuner on this one) (also probably much more than 350whp and more TQ than you can imagine)

or go process west top mount, BNR SuperCars built 18G get EWG and meth tune.

or PW top mount and BNR 20G and prolly get close to 350whp or just under with 800cc injs.

personally im running BNR 18g, with PW top mount, 750cc injs, AEM CAI, TXS catless TBE, good tune at 20psi and getting 335whp 360wtq. FUN car.
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Old 04-15-2010, 11:00 AM   #8
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Quote:
Originally Posted by hobbesnapoli View Post
http://surgeline.cobbtuning.com/dyno/index.php
Richard Zielinski -2010 STI

And you can page through and find others... for 350/350 you should go for a 20g / AVO380 / dom2.5 / etc

Supporting mods: Fuel pump, injectors, fmic, downpipe

Suggested: Intake & turbo inlet

Pretty simple


As far as the transmission goes- the older 5 speeds definitely had issues- but the rumor is that the new one have the LGT gears in them and are a good bit stronger... I haven't seen a broken one yet /shrug
Well that was quite useful! Thanks for the link. This was the basic set up that I had planned on doing. My only concern is the reliability of it. Again I worry about the rumor of the transmission as well as how the clutch will handle it. Again... Thanks, that is a useful link.
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Old 04-15-2010, 11:09 AM   #9
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Blackrex, out of curiosity why TMIC not FMIC? How is that holding up for you too? Would you make the same choice to go TM again?
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Old 04-15-2010, 11:16 AM   #10
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Quote:
Originally Posted by blackrex13 View Post
AVO turbos have performed poorly in use with our engines in the legacys and WRX's.

Our trannys are stronger than the 07 WRX trans so your HP numbers should be safe as long as you drive and do things sensible, any trans will break if you sit there clutch dumping at 4k rpm.

you could go front mount and use any old style 20g prolly 800cc injectors, and good tune.

any old 18g and run e85 and probably 1200+cc injs (consult with tuner on this one) (also probably much more than 350whp and more TQ than you can imagine)

or go process west top mount, BNR SuperCars built 18G get EWG and meth tune.

or PW top mount and BNR 20G and prolly get close to 350whp or just under with 800cc injs.

personally im running BNR 18g, with PW top mount, 750cc injs, AEM CAI, TXS catless TBE, good tune at 20psi and getting 335whp 360wtq. FUN car.
Some good healthy advice right there! Pretty much anything you hit with E85 on a slightly larger turbo and a good tuner will net you 350. You should look into an EWG set up and an EBCS for this type of power.

Will
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Old 04-15-2010, 11:18 AM   #11
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i wanted the quickest spool possible, and hell yeah i would do it again. this IC rocks. and its holding up great. the kit comes with new diffuser/splitter that utilizes the entire scoop and forces it air directly through the IC. even when hot ambient temps the cold side of the IC is very cool to touch, and the side to side longer path of this particular IC creates a better barrier for temperature isolation and has an elongated path of temperature gradient compared to all 08+ stock fitment ICs.


OH YEAH FORGOT TO ADD I HAVE GRIMMSPEED EBCS!!!!
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Old 04-15-2010, 11:37 AM   #12
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hello i'm just wondering how much hp can the 08 wrx take?

i'm thinking of changing my turbo to GT3037s
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Old 04-15-2010, 12:40 PM   #13
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Welcome! You're just up the road from me! I'm in Bethesda, MD. In fact, I just drove by Atlantic Motorsports yesterday on my way to the TurboXS shop.

I think there is solid advice in here. I've got a downpipe, cai, and fmic waiting to go on my 09 soon, and I'm thinking I'll be around 300whp. For going ahead from there, the next steps would be fuel pump, injectors, and a bigger turbo.

There are a few members from 3gwrx.com in the area here. We don't have regular meets, but it would be cool to hangout sometime!
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Old 04-15-2010, 12:52 PM   #14
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The 08 wrx can take the same amount of hp as all the other 2.5 liter ones in the past, but it's not like there is a specific number. Some people cAn have 600 whp and be fine for awhile whereas some people can have 350 and blow up their engine, it all depends
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Old 04-15-2010, 12:59 PM   #15
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dur4ce, I wish I was there man. Unfortunately I have a couple more years until I return. I probably wont be staying there either. I wish I could. I absolutely LOVE Maryland. I'll keep you in mind when I head back. There are meets down there but they are a decent drive. Have you checked into the MAIC meets forum? I think they are about 30-45 min from baltimore. Not worth a weekly trip but maybe once a month or so. Pretty sure they go to wild wings. Any way, if were both still using NASIOC by the time I am back in town I will hit you up and we can go for a drive.
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Old 04-15-2010, 01:07 PM   #16
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Quote:
Originally Posted by twentyclowns View Post
The 08 wrx can take the same amount of hp as all the other 2.5 liter ones in the past, but it's not like there is a specific number. Some people cAn have 600 whp and be fine for awhile whereas some people can have 350 and blow up their engine, it all depends
Thank you for your answer Twentyclowns

I'm from Thailand and there not many wrx around, so its really hard to gather infomation about the impreza

The infomation i got from subaru dealers here is that my WRX is the same spec. as the ones that gets imported to Australia,

Some people here say that the piston in the WRX 08 is SEMI forged and some say they are'nt which is confusing me...
this is the reason why i am still just "thinking" of changing to GT3037s

ps. Is 600hp possible in a 2.5 WRX with the internal of the engine standard?

thanks again
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Old 04-15-2010, 04:17 PM   #17
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^^ i think to get to those numbers internals need to be changed, i dont know any specifics though sorry
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Old 04-16-2010, 12:43 AM   #18
LilSubie
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at 600 HP you DEFINITELY need to upgrade your internals along with a LOT of other things. Back to the thread though...

I don't know crap about E85 and I'm sure there is a thread on here somewhere. Can someone send me in the right direction on the low down of E85?
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Old 04-16-2010, 04:27 AM   #19
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Quote:
Originally Posted by twentyclowns View Post
The 08 wrx can take the same amount of hp as all the other 2.5 liter ones in the past, but it's not like there is a specific number. Some people cAn have 600 whp and be fine for awhile whereas some people can have 350 and blow up their engine, it all depends
What utter nonsense...

Quote:
Originally Posted by GGS View Post
Thank you for your answer Twentyclowns

I'm from Thailand and there not many wrx around, so its really hard to gather infomation about the impreza

The infomation i got from subaru dealers here is that my WRX is the same spec. as the ones that gets imported to Australia,

Some people here say that the piston in the WRX 08 is SEMI forged and some say they are'nt which is confusing me...
this is the reason why i am still just "thinking" of changing to GT3037s

ps. Is 600hp possible in a 2.5 WRX with the internal of the engine standard?

thanks again
GGS, if you are indeed considering upgrading to a GT3076 (3037) setup, a built motor is going to be pretty much required step. Your car does not have "semi forged" pistons. They are hypereutectic cast.

[edit] To satisfy my own curiosity though, what octane fuels do you have available in Thailand?

LilSubie, a 20G will get you where you need. That's about the extent of where I'd want to go where you can still claim consistent reliability. Even then, a lot of people are still having failures in that range.

Last edited by Byzantium; 04-16-2010 at 04:33 AM.
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Old 04-16-2010, 05:48 AM   #20
LilSubie
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I laughed when I read that last post! You had to have rolled your eyes and bit your tongue!

I laughed when I read this.. I can tell your eyeballs rolled on that one. It is quite obvious though. I think that from my initial inclination and the advice I have recieved in this thread as well as PM's that if I want ~350/350 and maintain reliability (as best possible) I will have to go with the following set up:

20G Turbo upgrade
800cc Injectors
upgraded Fuel pump
Upgrade intercooler (TM or FM)
CA / SR Intake

All this on top of the current set up I have (see top of thread)

Now that I have made it this far I am still undecided on which specific products to go with. From my research I bleieve that Process west is the best TMIC and I like that if it is capable of massive cooling, capable of handling 350/350, then why not go with top mount for the quicker response?! I don't plan on going past 350/350 (would be nice but...) so that should suffice. With a 20G BNR turbo which brings up another question. Can I hook up an AEM CAI to this turbo? I would assume so. If so that would be my choice for the intake. Now for the fuel pump and injectors, can I get some recommendations on what you guys have used and would recommend?

Thanks again for all the support

Last edited by LilSubie; 04-16-2010 at 05:57 AM.
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Old 04-16-2010, 10:14 AM   #21
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Quote:
Originally Posted by LilSubie View Post
I laughed when I read that last post! You had to have rolled your eyes and bit your tongue!

I laughed when I read this.. I can tell your eyeballs rolled on that one. It is quite obvious though. I think that from my initial inclination and the advice I have recieved in this thread as well as PM's that if I want ~350/350 and maintain reliability (as best possible) I will have to go with the following set up:

20G Turbo upgrade
800cc Injectors
upgraded Fuel pump
Upgrade intercooler (TM or FM)
CA / SR Intake

All this on top of the current set up I have (see top of thread)

Now that I have made it this far I am still undecided on which specific products to go with. From my research I bleieve that Process west is the best TMIC and I like that if it is capable of massive cooling, capable of handling 350/350, then why not go with top mount for the quicker response?! I don't plan on going past 350/350 (would be nice but...) so that should suffice. With a 20G BNR turbo which brings up another question. Can I hook up an AEM CAI to this turbo? I would assume so. If so that would be my choice for the intake. Now for the fuel pump and injectors, can I get some recommendations on what you guys have used and would recommend?

Thanks again for all the support
the CAI connects to your inlet pipe, and WILL improve your HP and flow. dont buy an aftermarket turbo inlet, on the 08+ they are great from the factory unless yours is ripped or broken. the worst part of out intake is the 4inch long S coupler from the factory IC to throttle body. the PW IC replaces that. the BNR SuperCars turbo is a factory fit exact replacemnt. fitment is amazing because well you use a legacy turbo for a core!! are you looking at another bypass valve? you should consider, ours starts leaking at around 18psi and your turbo has to compensate for this. the GoFastBits has been recomended to me as a good low profile, well operating, replacement.
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Old 04-16-2010, 11:33 AM   #22
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I already have a GFB BPV actually . So for that 20G, do you send in your turbo and they modify it or do you buy a whole new turbo? Also, what are you using for fuel pump and injectors?
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Old 04-16-2010, 12:44 PM   #23
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Quote:
Originally Posted by Byzantium View Post



GGS, if you are indeed considering upgrading to a GT3076 (3037) setup, a built motor is going to be pretty much required step. Your car does not have "semi forged" pistons. They are hypereutectic cast.

[edit] To satisfy my own curiosity though, what octane fuels do you have available in Thailand?
there are 95 91 e10 e20 e85avalible in Thailand but i use E10

my current mods
-F-con v pro version 3.3
-custom 3inch exhaust (no CAT)
-EVC-5 hks boost controller
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Old 04-16-2010, 02:18 PM   #24
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Quote:
Originally Posted by LilSubie View Post
20G Turbo upgrade
800cc Injectors
upgraded Fuel pump
Upgrade intercooler (TM or FM)
CA / SR Intake
Add motor mounts and adequate suspension and braking mods that will support that kind of power and you're set.
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Old 04-17-2010, 02:05 AM   #25
LilSubie
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Thumbs up

See that's what I am talking about! Suspension and brakes definitely good supporting mods. I was waiting for someone to say that. Although I am curious on the motor mounts, why would you recommend that? I personally think the stock ones will work just fine but I am open for your thoughts on that one.
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