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Discussion Starter · #1 ·
I'm thinking I'd like to add a downpipe before my tune in late July (or, in prep for my tune) but know that fueling needs to be addressed also.

Is it it just the injectors, or do I need a fuel pump too? From reading, it looks like 725cc injectors are gtg for a protune, down pipe and sf intake.

I'll discuss this with the tuner as well, but wanted to get a head start here.

Again, only Want the parts needed to give support for the down pipe/intake setup.
 

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I'm thinking I'd like to add a downpipe before my tune in late July (or, in prep for my tune) but know that fueling needs to be addressed also.

Is it it just the injectors, or do I need a fuel pump too? From reading, it looks like 725cc injectors are gtg for a protune, down pipe and sf intake.

I'll discuss this with the tuner as well, but wanted to get a head start here.

Again, only Want the parts needed to give support for the down pipe/intake setup.
You should need a fuel pump, boost controller, and an air regulator also. At least I did when I went that route. Considering you are trying to do almost exactly what I did, I suggest just uninstalling the intake and go downpipe with a tune. Its a lot less expensive and the gains should be similar.

It is a lot of labor costs if you don't do it yourself, I did not which is why I am recommending just going stage 2 with a downpipe. I think stage 2 with a downpipe gets you around 280-290 whp whereas with all the fuel upgrades with intake and downpipe I got 300 whp on a protune.
 

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Discussion Starter · #3 ·
So you got 10-20 hp out of an intake, and the fuel mods to support it.

Not bad IMO. I'm assuming the overall driving experience is much better than the actual 10-20 hp you gained?

I install all my own parts..... always have.

I was called a shop in Utah today, Rallysport, and they suggested injectors and fuel pump to go with the down pipe and a tune (knowing I had the intake already).
 

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Stage 2+ here, intake/turboback/protune. 314hp/319tq on a mustang. I am still on stock injectors and pump tho and when wfo she is at 100% duty cycle. I plan on doing a few more things in a couple months (including fuel upgrades) and will get retuned again after. Until then i am trying to refrain from spanking on her too hard, haha!
 

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So you got 10-20 hp out of an intake, and the fuel mods to support it.

Not bad IMO. I'm assuming the overall driving experience is much better than the actual 10-20 hp you gained?

I install all my own parts..... always have.

I was called a shop in Utah today, Rallysport, and they suggested injectors and fuel pump to go with the down pipe and a tune (knowing I had the intake already).
Not bad? It costs him $1500 or so to get 10whp. That's not good at all, lol.

Fueling isn't required for a Stage 2 setup. Don't bother with fueling unless you're planning something bigger long term. If you're just planning to stay Stage 2, go with the intake for sound, and get a downpipe with a proper tune. Be done with it then. There's no point upgrading fueling when it's not even near being maxed out at Stage 2.
 

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Discussion Starter · #6 · (Edited)
Not bad? It costs him $1500 or so to get 10whp. That's not good at all, lol.

Fueling isn't required for a Stage 2 setup. Don't bother with fueling unless you're planning something bigger long term. If you're just planning to stay Stage 2, go with the intake for sound, and get a downpipe with a proper tune. Be done with it then. There's no point upgrading fueling when it's not even near being maxed out at Stage 2.
How do you come to 1500? And, why am I reading everywhere that stage 2+ on the 15+ STI requires fueling upgrades? Am I just one sided reading? I try to stay open minded. I don't ever see anyone suggesting that it's OK to add an air intake and downpipe without fueling upgrades on a 15+ STI.

I do read the EJ motor is very finicky, and it's nothing to play around with.

Hell, I've never owned a car that's required anything to run an air intake. So, what do I know.


I'm talking more of a stage 2+ vs. a stage 2.

I was looking at it as $300 for the intake, 600 for 725cc injectors and the fuel pump (fueling upgrades).

I have the intake already so I'd be looking at the downpipe cost, call it 600, plus 600 for the fueling.

If 2stroke is getting 314hp I'm looking at a hp gain of ~ 44 based on the stage 1+ numbers I was quoted by Surgeline tuning.... ~ 270

Also as I mentioned that 10-20 hp my make the car behave and feel a whole lot better than what the dyno displays on paper.

Stage 2+ without fueling is not something I'm willing to do.
 

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How do you come to 1500? And, why am I reading everywhere that stage 2+ on the 15+ STI requires fueling upgrades? Am I just one sided reading? I try to stay open minded. I don't ever see anyone suggesting that it's OK to add an air intake and downpipe without fueling upgrades on a 15+ STI.



I do read the EJ motor is very finicky, and it's nothing to play around with.



Hell, I've never owned a car that's required anything to run an air intake. So, what do I know.





I'm talking more of a stage 2+ vs. a stage 2.



I was looking at it as $300 for the intake, 600 for 725cc injectors and the fuel pump (fueling upgrades).



I have the intake already so I'd be looking at the downpipe cost, call it 600, plus 600 for the fueling.



If 2stroke is getting 314hp I'm looking at a hp gain of ~ 44 based on the stage 1+ numbers I was quoted by Surgeline tuning.... ~ 270



Also as I mentioned that 10-20 hp my make the car behave and feel a whole lot better than what the dyno displays on paper.



Stage 2+ without fueling is not something I'm willing to do.


You're missing the point that fueling and the engine is the exact same on the 2008-2014 and 2015+. Any threads on the GR/GVs will provide pertinent feedback. The big difference is the tune, but once you get to installing aftermarket parts, you're getting a custom tune so both generations end up being the same with a different curb weight.

From personal experience, fueling is not required until you swap a turbo, go for tgv deletes, or rebuild the motor.

Fuel pump $190
FPR $200
Injectors $500
Intake $300
Plus tax and shipping

If you're doing fueling, there's no point doing everything and not changing the regulator. You get pretty darn close to $1500 in comparison to a simple Stage 2. It's been proven time and time again that the intake provides no value other than sound at Stage 2 levels.
 

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My tuner recommended a fuel pump and EBCS for my GD back in 07 as well as my current 11. I did it because he recommended and I didn't know what mods I would do in the future. They are also cheap mods. I now run E85 on my 11 with 1100cc injectors which is a different scenario but I may have not "needed" a fuel pump for a 93 tune but 10 years and 160k trouble free protuned miles were worth the extra few bucks. Kind of like the AOS trend now. Nobody ever used them in early GD days but now people act like they are a requirement or your motor will blow up. For the OP, if you have a reputable tuner, I would follow their recommendations.
 

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Honestly, why even bother with 700cc injectors. The usual go to for injectors was 1000cc. Now i think they are being replaced with 1050cc. I would recommend going with Injector Dynamics (ID). It seems to be the most popular injector. You will also need a fuel pump to support those injectors. Speak with your tuner and see what they recommend.

If your are strictly going to just do intake and down pipe and NOTHING else down the road, then i wouldn't bother with injectors. I would only recommend upgrading your fuel system if you plan on going further than a bare basic stage 2.
 

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Discussion Starter · #10 ·
You're missing the point that fueling and the engine is the exact same on the 2008-2014 and 2015+. Any threads on the GR/GVs will provide pertinent feedback. The big difference is the tune, but once you get to installing aftermarket parts, you're getting a custom tune so both generations end up being the same with a different curb weight.

From personal experience, fueling is not required until you swap a turbo, go for tgv deletes, or rebuild the motor.

Fuel pump $190
FPR $200
Injectors $500
Intake $300
Plus tax and shipping

If you're doing fueling, there's no point doing everything and not changing the regulator. You get pretty darn close to $1500 in comparison to a simple Stage 2. It's been proven time and time again that the intake provides no value other than sound at Stage 2 levels.
I am so confused! :confused:

If 2014 model year is the same as the 15-17 model years, and the only difference is the tune, then why are there no air intake/down pipe packages or OTS tunes to support those combined mods offered from Cobb for 15-17 STIs?

Why do you have guys a couple posts up saying top priority is to add the fueling support because his injectors are maxed out with the air intake and downpipe? He's taking it easy on his car until he can do so.

Why when I call tuner shops (OK- I caught 2 on Saturyday) around the country do they tell me 'injectors and fuel pump' if you're going to add an air intake AND a downpipe?

I suppose the answer could be money for two out of the three above, but I'm just not getting that feeling from everything I've read.
:confused:
 

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Discussion Starter · #11 · (Edited)
Honestly, why even bother with 700cc injectors. The usual go to for injectors was 1000cc. Now i think they are being replaced with 1050cc. I would recommend going with Injector Dynamics (ID). It seems to be the most popular injector. You will also need a fuel pump to support those injectors. Speak with your tuner and see what they recommend.

If your are strictly going to just do intake and down pipe and NOTHING else down the road, then i wouldn't bother with injectors. I would only recommend upgrading your fuel system if you plan on going further than a bare basic stage 2.
I haven't spent a decent amount of time comparing pricing, but if the 725cc injectors are less, then why spend more now if the plan is to stop with the down pipe? I know, plans change. But, I really want to keep the mod bug down and going with injectors that leave headroom for the sole purpose of upgrades is just one more voice in my head telling me to go for it.

Again - I'm confused. I'm reading time and time again that there is good power to be had with the intake and down pipe combination, and less power without both.

Earlier in this thread, based off a posters dyno numbers, I figured it would be about 44 whp.
 

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You need to find a tuner in your area and do what he says you should do. Listening to some shmo on the internet who couldn't give a shit if you have issues down the road is pointless.
 

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I am so confused! :confused:



If 2014 model year is the same as the 15-17 model years, and the only difference is the tune, then why are there no air intake/down pipe packages or OTS tunes to support those combined mods offered from Cobb for 15-17 STIs?



Why do you have guys a couple posts up saying top priority is to add the fueling support because his injectors are maxed out with the air intake and downpipe? He's taking it easy on his car until he can do so.



Why when I call tuner shops (OK- I caught 2 on Saturyday) around the country do they tell me 'injectors and fuel pump' if you're going to add an air intake AND a downpipe?



I suppose the answer could be money for two out of the three above, but I'm just not getting that feeling from everything I've read.

:confused:


The 08-14 MY is the same powertrain wise as the 15+ MY, but the physical attachment points are different because of the new body style and new frame. Basically, the 08-14 AEM intake doesn't fit because it can't attach to the body the same way. They had to redesign their heatshield and spacer mounting locations to mesh with the new body. Same goes for the exhaust, it's still a sedan, but the body is different therefore fitment is not the same. Everything but suspension, interior and exterior is the same, and you have a sound tube connected to your stock inlet that goes into the cabin for added "sound".

You're asking for recommendations and you're getting them. Most of us have gone through what you're doing, and we know what we needed and what we could have passed on.

Were here to give you the feedback you're looking for. Sometimes, when you're not familiar with the platform, it's easier to follow your tuners advice. Like anything though, some tuners take advantage of their customers that don't always know what they need or don't need. It's no different than going to get an oil change, and the shop tells you your brakes are shot yet there are plenty of pad left, but you wouldn't know unless you asked and understood the pad measurements to know how much pad thickness is good and how much is bad. I highly recommend getting in touch with your tuner of choice, but do your research properly, know the reasoning behind an upgrade.

I'm telling you from experience, on 91 or 93 fuel, through extensive logging, fueling upgrades aren't "required". If you don't have a project plan, you're spending the money to make it easier on the next car's owner.

If you do anything, like I said before, there's no point increasing fuel pump flow at begining of the loop, and increasing injector flow at the end of the loop, but not upgrading the regulator that actually controls that flow.
 

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Discussion Starter · #14 ·
The 08-14 MY is the same powertrain wise as the 15+ MY, but the physical attachment points are different because of the new body style and new frame. Basically, the 08-14 AEM intake doesn't fit because it can't attach to the body the same way. They had to redesign their heatshield and spacer mounting locations to mesh with the new body. Same goes for the exhaust, it's still a sedan, but the body is different therefore fitment is not the same. Everything but suspension, interior and exterior is the same, and you have a sound tube connected to your stock inlet that goes into the cabin for added "sound".

You're asking for recommendations and you're getting them. Most of us have gone through what you're doing, and we know what we needed and what we could have passed on.

Were here to give you the feedback you're looking for. Sometimes, when you're not familiar with the platform, it's easier to follow your tuners advice. Like anything though, some tuners take advantage of their customers that don't always know what they need or don't need. It's no different than going to get an oil change, and the shop tells you your brakes are shot yet there are plenty of pad left, but you wouldn't know unless you asked and understood the pad measurements to know how much pad thickness is good and how much is bad. I highly recommend getting in touch with your tuner of choice, but do your research properly, know the reasoning behind an upgrade.

I'm telling you from experience, on 91 or 93 fuel, through extensive logging, fueling upgrades aren't "required". If you don't have a project plan, you're spending the money to make it easier on the next car's owner.

If you do anything, like I said before, there's no point increasing fuel pump flow at begining of the loop, and increasing injector flow at the end of the loop, but not upgrading the regulator that actually controls that flow.
Acknowledging I'm completely new to Subaru and their turbo motor, but not new to modding FI or NA motors whether that be on land or water.

I don't NEED a cast when I break my arm, and I don't go to the hospital because the doctor who is making money suggests it. I'm going because I know I'll get a better end result if I take the proper measures.

I do appreciate your input. Perhaps you could link a couple sources, be it threads or other data, that explains how a 15+ STI with an air intake and downpipe does not "require" fueling upgrades. I'm all ears man.... I'm all for not having to spend on fuel upgrades. I'm all for feeling confident my motor is GTG with a downpipe air intake and dyno tune.
 

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Discussion Starter · #15 ·
You need to find a tuner in your area and do what he says you should do. Listening to some shmo on the internet who couldn't give a shit if you have issues down the road is pointless.
For sure. It's already done and I'm on the schedule for their dyno tune. They're all out of town this weekend so I thought I'd get some 'pre-tuner conversation' data here.

A discussion with Lance at Surgeline is forthcoming. :tup:
 

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So you got 10-20 hp out of an intake, and the fuel mods to support it.

Not bad IMO. I'm assuming the overall driving experience is much better than the actual 10-20 hp you gained?

I install all my own parts..... always have.

I was called a shop in Utah today, Rallysport, and they suggested injectors and fuel pump to go with the down pipe and a tune (knowing I had the intake already).
I enjoyed the intake the most probably. I went from Cobb Tune with Intake to Stage 2+ with a protune so there is a large gap. Power wise I gained a lot from the Cobb tune at least it felt like it did, however the smell is kind of annoying and I like the intake noise the best.

If I had to do it over again I would only install a downpipe and either use the Cobb tune or get a protuned on stock fueling with just a downpipe. I agree with Nox that the fueling upgrades just to accommodate the intake is not worth it. I spent a lot of money that I really didn't need to because I thought it would be better. If you are set on going stage 2+ go for it, but from my experience it is not worth it compared to just a downpipe.

I think BrenTuning took down their protune examples but they used to have examples of people's builds with protunes and it is really quite similar in power with/without intake. I did not plan on going for a bigger turbo or any other upgrades so the upgraded fueling is really silly in retrospect

TLDR: Just go Stage 2, uninstall the intake, and save money
 

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I am so confused! :confused:

If 2014 model year is the same as the 15-17 model years, and the only difference is the tune, then why are there no air intake/down pipe packages or OTS tunes to support those combined mods offered from Cobb for 15-17 STIs?

Why do you have guys a couple posts up saying top priority is to add the fueling support because his injectors are maxed out with the air intake and downpipe? He's taking it easy on his car until he can do so.

Why when I call tuner shops (OK- I caught 2 on Saturyday) around the country do they tell me 'injectors and fuel pump' if you're going to add an air intake AND a downpipe?

I suppose the answer could be money for two out of the three above, but I'm just not getting that feeling from everything I've read.
:confused:
Unless I'm not reading this post correctly, there is COBB OTS tunes for stage 2 with downpipe, and a separate OTS tune for stage 2+, with downpipe and intake.
 

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Unless I'm not reading this post correctly, there is COBB OTS tunes for stage 2 with downpipe, and a separate OTS tune for stage 2+, with downpipe and intake.

I don't and haven't seen a OTS tune for stage 2+ on Cobbs site. Apparently they released one for a very short period of time before deleting it and saying you needed fuel upgrades along with it. I'm sure some people got their hands on it and saved it before it was taken down.
 
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