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Need feedback ASAP

7K views 55 replies 11 participants last post by  dumdum 
#1 ·
Hi All, long story short: I have 05 WRX, 46K miles. Rod is bent and dealer is replacing block and pistons under warranty. Approx two weeks of rental car on my own dime (just complaining)... each day adds up though.

To take advantage of the situation, I am doing upgrades and "early mainentance." Just found this forum. Ordering parts in next day or so.

Proposed "early maintenance" = new timing belt (i.e., only at cost of belt), replace clutch with STI ceramic clutch assembly.

Proposed mods (all STi and Cobb where possible):

STi turbo
up-pipe
downpipe
keeping stock cats* but replacing all other exhaust, turbo back
cold air intake
BOV

*I've been told that stock cats are minimally restrictive. I was told that high-flow cats by comparison are not worth the extra $ in terms of bang for buck.

Me - once all done, Cobb AccessPORT - have friend (currently can't reach him) who can set up/tune.

The above list nearly zero's out my budget.

Anything I'm missing that would be a low-cost no-brainer to add at this point? For example, should I be looking at injection system or fuel pump? Should I replace engine mounts? Should I consider upgraded intake manifold and intercooler in exchange for somethintg on the above list.

Sorry about all the newbie questions. This came up fast and the time window is short!!

Many thanks for ANY feedback!!!!
 
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#2 ·
Cold air intake will require a custom tune (a regular Cobb AP Map will not give you the right AFR), and the stock air box is more than enough for your power level. Also the BOV is not necessary unless you plan on running more than 20PSI+, even then you can mod it to work. If your doing a BOV get a recirculating one (i.e. the Perrin) as that is easier to tune with and does not mess with the AFR like a VTA BOV.

I am not sure how your gonna use a STi clutch assembly (the STi is a 6 speed tranny) and your '05 WRX has a 5 speed so that will not work. I suggest the Exedy OEM replacement clutch or if you want a little more bite the Exedy Stage 1 Organic Clutch. Additionally, you don't have to run any cats in FL (no emmissions testing), the stockers would be a restriction. If you want a cat I suggest getting a Bellmouth DP with a Cat (i.e. Invidia or Cobb).

Finally, you may need a 3 port BCS (i.e. GM, Perrin, Mach V), fuel pump (Walbro 255), bigger TMIC, and injectors (atleast 565cc but I would go 650cc for more headroom). But, I would consult your tuner about that. Lastly and foremost, find a good/experienced tuner.
 
#3 ·
List of bad things to do:
Clutch
BOV
CAI

Also, the "STi Turbo" will require:
-catless up-pipe
-bigger injectors
-bigger intercooler
-bellmouth downpipe removing the stock catalytic converters (not nessisarily catless)
-Most probably a cat-back exhaust
-some engine management for a re-tune

Read Cobb's AP map for an 05 WRX with a VF39 (04-06 USDM STi Turbo) for example:
http://www.accessecu.com/accessport/subaru/new/05 WRX/Map Notes/STi Pink 2.0L VF39 93 v100.pdf

Note it specifically warns against aftermarket intakes:
"MUST USE FACTORY INTAKE SYSTEM OR COBB SF INTAKE ONLY"

My advise is to slow down and do your homework. Cheaper to fix things right the first time.
 
#4 ·
Thanks to both of you. Agreed, better to slow down and deal with extra cost of rental car... small $ in comparison. Tomorrow I will know much more about parts/brands being reccommended by parts dept. Trying to work this where warranty will be OK when all is said and done. May not be possible or may not be worth the effort balanced with the possible gains.

I must have misunderstood about the STi clutch. I'll have more details late morning Tuesday/tomorrow and will post them here. If you have a chance to check back in, it would be much appreciated. Thanks again.
 
#5 ·
yea for real, i would get it fixed first and then upgrade later. since you are getting a new block im assuming it will be under warranty after the replacement and if they mess it up or it something happens to it again im sure they wont cover it if you do performance upgrades.

Just take your time, and save yourself some money as the rental alone will be expensive.
 
#8 ·
I tried to stay in a Holiday Inn Express last night and today... and still reading the amazing manifesto. That said, I have had lengthy talks with a couple of very WRX-tuning savvy folks. Also got rid of rental car and have a loaner car... not in a rush now.

I broke my engine... ?, never red-lined it. It was check out and is fully covered by warrantied. The shop told me they have had a few WRX's come in with this problem.

Side note: I swore to myself that when the STi came out in a wagon, I would buy one... that was then. This economy's now.

So, thanks to your input, info from reading and conversations, and my hankering for more HP for ~3 years, here's where I'm at:

[I should also mention I'm in the hands of a good tuner man and I am in learn mode bigtime... may be getting in over my head, but it's hard to pass up on the free labor for all these mods!]

Cobb Tuning Cobb Stage 2 Power Package(WRX 2002-05)
-Catted Downpipe (my pref)
-Cat-back Exhaust
-Accessport
Cobb Tuning 712100 SF Intake System
Cobb Tuning Lightweight Main Pulley
GrimmSpeed UP Up-pipe w/ Flex Section ceramic Coated
HKS 71004-AF008 HKS SSQV Direct Bolt On BOV Kit (recirc)
TurboXS Top Mount Intercooler Kit
Walbro 400-791 Walbro Installation Kit / Subaru and
Walbro GSS342 Walbro 255 Fuel Pump
NGK BKR7E Heat range 7 Spark Plugs / WRX
Subaru SPT ceramic 5sp clutch assembly
STI/SPT turbo (specs pending)

Things for later once I learn more include injectors, etc.

I appreciate the comments and welcome more. Yes, I'm jumping in the deep end, but I have a lifeline and a tuner friendly shop.

PS. The clutch may be a couple of hours extra labor... otherwise, it's cost of parts.
 
#9 ·
These are a waste of money on a stage 2 car.
Cobb Tuning 712100 SF Intake System
HKS 71004-AF008 HKS SSQV Direct Bolt On BOV Kit (recirc)
TurboXS Top Mount Intercooler Kit
Walbro 400-791 Walbro Installation Kit / Subaru and
Walbro GSS342 Walbro 255 Fuel Pump
NGK BKR7E Heat range 7 Spark Plugs / WRX
But it's your money.
Make sure you get tuned because the OTS Cobb map will not be happy.
 
#12 ·
I'll put that comment in front of my two "advisors" to see what they have to say in defense. Everything they proposed sounded logical to me except for the BOV, but I was told the stock BOV has a small leak at high rpms and and the aftermarket BOV would keep pressures more stable/smoother across the higher range, plus no leaks... maybe a bill of goods?

Nobody suggested the intercooler until I brought it up, and the reply was that the stock intercooler was minimally effective and that now that I'll be generating more heat under the hood, it would be a smart thing to do. Not sure how more/cooler air and larger turbo are a waste of money when I'm increasing exhaust flow.

Should I not put in the upgradded fuel pump until I get to the injectors?

Injectors are eminant, but I have to draw the $ line somewhere. Maybe I'm going overboard trying to take advantage of the free labor.

I realize the canned Cobb maps are not going to fit this glove well, and yes I will get tuned.
 
#13 ·
Why are you stuck on the STi turbo? Take a look and see what blouch, FP, etc have to offer. that car can easily handle an 16G or 18G and not have to change the intercooler setup from TMIC to FMIC. Also i would do everything in stages and not just dump a butt load of performance parts on the car, for the reason of understanding how the car is going to react and the simple matter of driving it.

Also with a quick note about your clutch that nobody has mentioned. Stock Transmission = Stock Clutch. If you get a "Grabbier" clutch you run the risk of stripping gears in the tranmission.
MOSC or one of the other smarter guys can explain it better than i can.
 
#14 ·
You should have a VERY short list for this project if your budget is so tight:
Catted downpipe
Cat back
Catless uppipe
Cobb AP
DONE

As for your stock BOV leaking, I run a larger turbo than you pushing more air with more boost on the same BOV and I have no leaks. You're getting bad advise.
 
#16 ·
Your "advisors" want you to send money, plain and simple.
With the mods you have listed you will need a Protune on the AP, an OTS map will not work.
If these guys that want you mod like this are also your tuners, find another tuner. These "advisors" are leading you down a bad path that will cost you more money in the long run.
You need a game plan, DD, track car, autoX or drag car. All will need a different setup to be the best it can. Throwing a bunch of mods at your car without a plan, is a waste of time and money.
 
#17 ·
Thanks OFracer.... like the name. OldFart was my Call of Duty handle.

Anyway, I told them my game plan up front: this is my day-to-day car, and I take it off road (and camping/fishing/hiking - I'm a geologist), and distance trips where I like to go fast in the boonies. Also like occassional spontaneous street drag if safe. And nobody likes turbo lag. So I guess my game plan is sort of a hybrid/sleeper. Or, like I said, this is the STI I can't afford.

Responses to questions:

The local shop encouraged SPT mods/upgrades to maximize odds of warranty being honored down the road. That's why the bias toward the STI/SPT turbo. Shop reccommended SPT and Cobb for the most part - nothing bad about those parts I could see so I went with their recommendations. Bought other parts from large online dealer and we discussed pros/cons of each part, compatibility; he took %age off online pricing, and threw in free plugs and shipping. Conversation did not feel like I was being pushed, but I question the BOV...

Since this situation came up so fast, and I generally don't tinker with cars, I was looking at this as a one-shot opportunity to upgrade. I like the idea of doing this in stages. On the other hand, the local "advisor" does not seem too concerned with the need for custom AP tuning.

Maybe I should return the BOV for injectors?

Regarding the clutch, I confirmed today it is not the ceramic assembly but the STI organic assembly, which is totally OK to use with my stock trannie. It's still reportedly a big improvement over stock clutch. I'll chat with them about doing this in stages because I do want to learn and not black box this whole thing.
 
#19 ·
You can't effectively run an STi turbo on your car without bigger injectors. You will be limiting yourself a lot if you don't get bigger injectors.

You don't need a BOV unless your stocker leaks. Some leak over 18 PSI and some don't.

Unless you stick to the parts listed in the map notes for the Cobb maps you will NEED to have a custom tune. No if's and's or but's about it.
 
#20 ·
Thank you. I hear you and I appreciate it.

I'm re-thinking all of this, and now find out that the Cobb SF intake and stage II are backordered; a TXS intake and an Invidea catted downpipe and cat-back have been suggested as replacements.

Words from one of my advisors:

"With the Cobb Stage 2 package, the stage 2 is for the parts, when you actually hook up your Cobb accessport, there will be different maps in there showing different modifications like; intake, header, exhaust, 93 octane fuel. Or Turboback only 93 octane etc etc.

With what your going to be running the Map after the Stage 2 on the Accessport will do you just fine. That map has been continuously used for up-pipe, intake, and turboback exhaust.

Your fuel pump will not change any of the parameters of your cars tune.
The fuel pump is an extra precaution because the ECU will be demanding more fuel and your stock fuel pump might not be able to keep up with the request from the ECU.

Even though the ECU will be flashed with the accessport, your ecu will still have its full ability to change correction factors for the Injectors, Mass Air Flow Sensor, and Knock sensor. These are the three keys to keeping your car running correctly. If the ECU notices too much boost, or too much fuel it will correct it by fluctuating the injector pulse and boost control solenoid to keep the Air fuels in check."

One implication is that the stock injectors can handle some amount of increase in flow from an upgraded fuel pump. Another implication is that the OTS maps plus the normal real-time adjustments by the ECU can handle the situation. Despite what he says, I do get that a custom map is likely needed.

Also going to talk with them today about doing this in stages as suggested. I have no other options for local advisor... am trying to balance all feedback here with that of current advisors.

I appreciate all the input and will keep you posted... sit back and watch me either inch forward in stages, or push it all on at once and have a trainwreck. ;)
 
#29 ·
"With the Cobb Stage 2 package, the stage 2 is for the parts, when you actually hook up your Cobb accessport, there will be different maps in there showing different modifications like; intake, header, exhaust, 93 octane fuel. Or Turboback only 93 octane etc etc.

With what your going to be running the Map after the Stage 2 on the Accessport will do you just fine.
Stage 2 map is for a stock turbo only!Either you are very confused or they are.Are you going to use the stock turbo or upgrade to a bigger one....
pick one:)
Mr.Happy said:
If the ECU notices too much boost, or too much fuel it will correct it by fluctuating the injector pulse and boost control solenoid to keep the Air fuels in check."
The ECU can only correct fueling in closed loop where it uses the O2 sensor feedback.In Open loop/WOT the ECU does not have the ability to make immediate fuel corrections.Any professional tuner know this and this is why you pay for their services as they have tools like a wideband AFR sensor to read the fuel mixture at WOT.
 
#26 ·
JSC Speed: Performance Parts Warehouse
Has the Cobb SRI in stock. I would also get the Cobb Air Box to go with it (helps lower the temps). However, as I stated earlier your stock intake really is not a limiting factor at your power levels.

Also, I would do your homework and find a better/more experienced tuner in your area. To bad your in North Fla b/c if you were down here in SFLA, I could send you to a badass shop with a very experienced engine builder/tuner that specializes in WRX/STi/Evo builds and tuning.

What part of North FLA are you in? B/c I used to live in Gainesville a few years back when I went to UF and depending where you are I may know someone who can help you out.
 
#30 ·
All - Here's where I am now (or what I've gotten myself into now!):

Local tuner advisor: ex-racer, 14 years exp., his first car he bought best parts available but had nightmare getting them to work together... learned his lesson. Taking alot of time answering my questions. He referred me directly to parts company so I could save on markup his local shop requires. Urged me to have detailed discussions with tech pros at parts company. I have done this several times.

Distant advisor 1: Very responsive and knowledgeable, 8 years experience and has seen all sorts of combinations work as long as tuning is good. Yes, he is also parts manager for reputable online supplier. He firmly stands behind the package he sold me and has seen it work.

Distant advisor 2: You folks - and I thank you again.

Me: quick study in technology; know that life with physics and computers (i.e., I use electron microprobe often) ranges from black and white to all shades of gray. Must set-up, test, calibrate, validate, monitor, maintain. Not much time to devote to this and need my car back! I'm the kind of guy who eats at "hole in the wall" restaruants when traveling... I avoid chain restaurants at all costs. I average food poisoning once every 16 months; however, I discover many outstanding local food dives during the year!!

Distant advisor 1 and local advisor rarely agree with absolutes offered by Distant advisor 2. :)

My 05 wrx is on rack waiting on warranty replacement engine and parts.

I have ordered the following parts, which is different from original list due to back-order items. I stayed with original parts dealer becuase he packaged purchase to cut my cost, added free shipping and free rush shipping for uppipe. Also his prices tend to be among the lowest online, at least for what I bought. He is Distant advisor 1.

PARTS

From Subaru SPT:
Organic STi clutch
STi turbo (not a huge jump over wrx stock but enough for me)

From parts Co.:
GrimmSpeed Up-pipe w/ Flex Section ceramic Coated
Cobb Accessport
Invidea catted downpipe
Invidea G200 catback system
TXS SF intake
Cobb Tuning Lightweight Main Pulley
HKS 71004-AF008 HKS SSQV BOV Kit (recirc)
TXS TMIC Kit
Walbro GSS342 Walbro 255 Fuel Pump and install kit
NGK BKR7E Heat range 7 Spark Plugs

Why fuel pump (from Unabomber): "Can I run an aftermarket fuel pump by itself without new injectors/turbo/management? During the turbo upgrade path, it may be easier to purchase and install a fuel pump ahead of time. It is cheap, easy to install, and removes an eventuality from the upgrade chain ahead of time. You can run an aftermarket fuel pump with no other modifications. Adding a fuel pump will not give you more fuel (i.e. richen your car), it simply allows for more fuel to be delivered if you run higher boost or larger injectors. The stock RRFPR keeps the pressure at the stock 43 psi + manifold pressure no matter how much fuel may be available from the pump."

Cobb AP may not work with TXS intake among other things: I have been told the combo works or else it would not have been sold to me. Despite the Cobb statement "For use with a VF30 turbo, STI (pink) injectors, stock intake or Cobb SF intake and a TURBOBACK exhaust system. Additional modifications such as uppipe and underdrive pulley are still within the acceptable parameters of this mapping. MUST USE FACTORY INTAKE OR COBB SF INTAKE SYSTEM ONLY. NO OTHER AFTERMARKET IN TAKES ARE CERTIFIED COMPATIBLE WITH THIS MAPPING. [doesn't mean they arent compatible] Uppipe is highly recommended when using any aftermarket turbochargers. If adding an upgraded intercooler, monitor boost and EGT levels for boost spiking or high temperatures."

As a start on tuning, Distant advisor 1 said "When the parts are installed load the map on the accessport right after the stage 2 map if there is any issues I will take care of it by getting you in contact with the many Subaru only shops in FL I sell wholesale to." I will also email my configuration to Cobb and request a custom map as a backup starting point.

Local advisor 1 says we will work though it. I need to confirm he has a wideband. He does not have dyno... which is obviously where I may end up with a protune.

I may be putting that BOV on ebay (or returning it) and going with pinks injectors... I may be making that trip to Gainesville or points south for a good tune. ONe thing I know for sure, I'll be using synthetic oil from now on.

So, I'll keep you posted with the good, bad and ugly. Sit back and enjoy the show. Hopefully I will not have a food poisoning experience! :poorme:
 
#31 ·
DO NOT RUN THE STI TURBO ON THE STAGE 2 COBB MAP!

You will blow up your motor again. You need another advisor.

There is a Cobb map setup for the correct turbo. If you run the stage 2 map with the VF39 or 43 you are going to lean your A/F way out. The STi turbo flows a lot more air than the stock WRX turbo.

http://www.accessecu.com/accessport/subaru/new/05 WRX/Map Notes/STi Pink 2.0L VF39 93 v100.pdf

VF39 turbo, STi TMIC, STi "Pink" 565cc injectors & Turboback exhaust using 93 octane

You need to get bigger injectors and run the proper map or you are going to destroy your motor again. Call Cobb/PDX Tuning/Surgeline Tuning and talk to them or another real tuner. We are just trying to help you not destroy your car. Please get some advise from a tuner. Any of these guys can give you some real good advice:

Welcome to 555 Motorsports
CAMTuning.com - Custom Engine Management and Performance Tuning Solutions
awdtuning.com - Main Site - Subaru Performance Tuning
MPS™ :: Custom Tuning Services “Get a Dom Tune!”®

With the exception of your tuning and injector choices, it looks like you have a good selection for the parts. The BOV isn't necessary but it will work.
 
#32 ·
DO NOT RUN THE STI TURBO ON THE STAGE 2 COBB MAP!

You will blow up your motor again. You need another advisor.

There is a Cobb map setup for the correct turbo. If you run the stage 2 map with the VF39 or 43 you are going to lean your A/F way out. The STi turbo flows a lot more air than the stock WRX turbo.


http://www.accessecu.com/accessport/subaru/new/05 WRX/Map Notes/STi Pink 2.0L VF39 93 v100.pdf

VF39 turbo, STi TMIC, STi "Pink" 565cc injectors & Turboback exhaust using 93 octane

You need to get bigger injectors and run the proper map or you are going to destroy your motor again. Call Cobb/PDX Tuning/Surgeline Tuning and talk to them or another real tuner. We are just trying to help you not destroy your car. Please get some advise from a tuner. Any of these guys can give you some real good advice:

Welcome to 555 Motorsports
CAMTuning.com - Custom Engine Management and Performance Tuning Solutions
awdtuning.com - Main Site - Subaru Performance Tuning
MPS™ :: Custom Tuning Services “Get a Dom Tune!”®

With the exception of your tuning and injector choices, it looks like you have a good selection for the parts. The BOV isn't necessary but it will work.
OP-Read the stuff in bold as this is the second time it's been said.I don't think you getting this.Read my last post again as well.You can read all the premade map notes on Cobb's website.Oldfartracer even posted a link to the stage 2 maps notes and you clearly missed "for stock turbo only".And which "STI" turbo??There are like 6-8 different ones...........only certain ones will work with Cobb's premade maps.I can guarantee most of the guys here know more (much more) about these cars than the people you are talking too.I have been wrenching on cars myself for 20 years and self tune my current car(and friends) along with installing/performing all my modifications as well as doing my own turbo rebuilds and porting /polishing work.We are trying to save you some serious heartache but you need to take heed to the stuff we are saying(especially the stuff in bold!!!):D
 
#33 ·
Ok maybe im reading this all wrong, but you are wanting to put on the STI turbo, and stay with your stock injectors, and just run the stage 2 COBB map? and also have all those other bolt on mods like exhaust ect....???? and why are you putting on another BOV for stay with the stock one!! Are you going to get a protune after you put this turbo on and all the other bolt ons??
 
#39 ·
Just to clarify, my plan was (is?) to upgrade to an STi turbo, stay with stock injectors for now, NOT run a Cobb Stage 2 map, but either "the map in the Cobb AP listed 'after' the stage 2 map, or a custom map, based on work of a good tuner. Yes, bolt on exhaust as described above.

I will be present for the tuning (want to watch/learn, and keep in mind all being said here), and will be quick to pull out of shop if they appear to be winging it and/or don't have appropriate gauges/monitoring (AFR, etc.). I will also make sure tune is good at WOT.

Right now, (for now?), my major regret is the BOV. Injectors are an eventuality. Sounds as if I'm wasting time/money with upgrade to STi turbo if I don't go ahead with injectors. Any logic to getting what I've got running before upgrading injectors?

Willl be researching and having chats with some/all of these folks:

555 Motorsports
CAMTuning.com
awdtuning.com
MPS™ Custom Tuning Services
Elementuning.com

Thanks for all the feedback!
 
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