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Discussion Starter #1
the subject has been brushed before, but i wanted to discuss it more.

I currently have a SPT cat back, and that is my only mod. I am itching like crazy to get an intake to add a little bit more throttle response and more importantly hear that turbo. This is my first turbo car, and i cant help it but i really just want to be able to hear it, there something about that spool and pssh sound that gets me going.

I also plan on adding a downpipe later on, as well as getting an acessport and tuning the car for sure... but the accessport is quite expensive, where as an intake is do-able before the end of the year. I most likely won't get the AP untill next spring/summer. So my question is, will my engine be fine? Will I need to worry about anything running those 2 mods without a tune for 6 months or so? I have heard differing opinions on this, but hopefully since this board is dedicated to the new platform, we can come to a general agreement on this subject.

My power goals are simple, I want to be able to take stock sti's, maybe very lightly modded ones. Would TBE, intake, and a tune accomplish this? What other light mods are possible? I do have a lifetime powertrain warranty, but the service manager at my dealership is really cool and im pretty sure he'll let a downpipe fly. This may be a different discussion, so if it's not to relevant to this thread we can continue elsewhere, but i am curious what else there is without getting tooo obvious [like no FMIC]

thanks in advance
 

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I dont think anyone has datalogged w/ the intake and SPT exhaust only. It's still a bit tough to know which intake doesnt require a time (although it's still suggestible). Beware though, the stock intake box has a air straightener/diffuser type mechanism. I have read some aftermarket intakes do not have these. Before you buy 1, make sure it has the straightener/diffuser, and a good one too b/c the intake DIY install on this forum showed an AgencyPower intake with not so straight straighteners.
fwiw, I have SPT exhaust and AEM intake.
 

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Discussion Starter #3
I am pretty sure the AEM intake is at the top of my list, unless we get the SPT one released in the next month or so. Do you have yours tuned? If not, are you worried about anything? How's the car feel? Have you done any monitoring aside from the stock insturments?
 

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I did a datalog with my STi on the new stock tune and a 3" midpipe upgrade. Should be similar to the components you are measuring. The designs of the Injen and the AEM are also very similar so the results should be approximately the same. I ran of course a 14.7 AFR on idle and the leanest all the way up to redline was a 12.7. This is a hair towards the lean side. I contacted Injen and they claimed high 11 to low 12s but yeah might be the midpipe that leaned it out a bit more. You can make your own inferences here. After the tune, I am running 12.4 all the way to red. I like to play it safe. :)

Better throttle response and boost kicked in about 150rpm sooner.
Remember also that not all vehicles react the same way to mods. You could run richer and leaner than I am. I am just trying to provide a bit of info for you to start with.

Hope this helps you out.
 

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Discussion Starter #5
with this information, do you think i would have anything to worry about if i were to run an AEM or Injen with the SPT exhaust and no tune for say 6 months or so?

sorry for re-iterating my question, but this is my number one concern at the moment, with the performance aspect right after.
 

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Kind of a risky question but I'll give it a shot. For 6 months, assuming you drive like a granny, it wont matter. = No boosting, you can even have a 1000 shot NOS and it wouldn't matter so long as you didn't use it.
If you like spirited driving. Anything in the mid 12 AFR range is fine, in the upper 12 range, like you might be in, this might spike to 13s on occasion and this is the gray area. Assuming your sprited driving only lasts for short bursts, and/ or on occasion you should be ok. If you drive hard day in and day out, you are going to want to consider getting a tune sooner.
"Safe" is in the eye of the beholder. How safe would ou like to be? Personally I would not even want the Cell to pop in the first place so I try to avoid the risk.
My advice, you can install both pieces and be ok for 6 months, just don't have a lead foot for the time being.

Have fun but be safe ;)
 

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I am pretty sure the AEM intake is at the top of my list, unless we get the SPT one released in the next month or so. Do you have yours tuned? If not, are you worried about anything? How's the car feel? Have you done any monitoring aside from the stock insturments?
I unfortunately am still on crappy stock tune. I am a bit concerned, but similar to what TougeMonster is saying, I dont have a heavy foot (I get ~26MPG in my mix driving). I have only floored it 2-3 times since the install. Honestly, the stock tune on the 08 causes the car to run very lean in the lower engine speeds, it's not until the upper engine speeds where boosting seems safer. This has been verified by several tuners. The car feels fine, no CEL. Throttle response is better, and when I did floor it, the powerband smoothed up a little and the power doesnt fall quite as harshly as stock.
My advice would be to wait. If you are looking to get 1, just go easy till some sort of tune is had. And I'm sure you already figured it out by now, I do suggest reputable brands.
 

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Discussion Starter #8
hmm... i do like sprited driving, and after a new mod [I already have the SPT cat back on] im sure I would have a hard time staying calm with my lead foot.

so i guess that leads me to another question, is there an inexpensive way to do some light tuning without the accessport? Or maybe just adjust the AFR slightly? $260 for just an intake is alot more do-able in the next few months, rather than waiting till I save up almost $900 for the AP and intake combined. I know i am being impatient... but i can't help it.

is this the reason they won't release an SPT intake for us yet? Due to ill effects without tuning it?
 

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This is just my experience so take it as you will. I have a UR catted DP, SPT exhaust and a high flow panel filter with no tune. I have had the DP and filter for about 6 months and I run it like a stole it a bit. I have experienced no CEL, I also have a cheap boost guage and it has showed nothing over around 13-15 PSI obviously it isn't an exact number but I haven't had any fuel cutoff from overboost. With the SPT exhaust installed I ran an Auto-X this weekend and ran the hell out of it and didn't have any CEL or overboost effect either. I have no idea what the AFR is in this config but it isn't far enough off to make the computer throw a code. I don't know what would happen if I had an intake. There is a definitely feeling of more HP and torque from the ole butt dyno with no ill affect so far.
 

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There was a note in my Perrin CAI that says you can use the intake on an otherwise STOCK car with NO aftermarket tune... it didn't say you could do it with a catback though.

Now that I have the AP and Perrin DP, I have to tell ya... the AP and a good tune (like Perrin's) is worth EVERY penny. The car is SO much smoother than it was. It used to surge all over the place and was just annoying. Now the throttle response is near-instant, boost spools much quicker (I can downshift to 3rd, take a turn and it doesn't fall on its face anymore), and it's just a LOT better.

IMO, a Stage 1 tune would be better than a CAI.

Rob
 

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This is just my experience so take it as you will. I have a UR catted DP, SPT exhaust and a high flow panel filter with no tune. I have had the DP and filter for about 6 months and I run it like a stole it a bit. I have experienced no CEL, I also have a cheap boost guage and it has showed nothing over around 13-15 PSI obviously it isn't an exact number but I haven't had any fuel cutoff from overboost. With the SPT exhaust installed I ran an Auto-X this weekend and ran the hell out of it and didn't have any CEL or overboost effect either. I have no idea what the AFR is in this config but it isn't far enough off to make the computer throw a code. I don't know what would happen if I had an intake. There is a definitely feeling of more HP and torque from the ole butt dyno with no ill affect so far.
I have absolutely no doubt there was a huge power gain going to a stage 2 untuned. 13-15 psi with an engine that was tuned to go much lower boost however becomes the issue. I really hope that you aren't running lean. But the CEL only pops if the AFR reaches dangerous levels, no less. Then again, after 17psi or so. Ultimate-Racing.com should give you an approximation of how much power you are running as they did these dyno tests on an untuned WRX also. As far as AFR, I believe someone from nasioc contacted them and they were viewing about a mid 13 AFR with those mods. Amybe shoot them an e-mail and ask "what would my AFRs be if I installed your intake and exhaust alone?" I am sure they will provide you with the information you seek.

Good luck and happy modding
 

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im in the same place you are, i REALLY want an intake but dont have the money for my AP just yet. I went with this route till then. http://www.3gwrx.com/forum/index.php?topic=2183.0 and its satisfied my turbo noises craving for the time being. I can hear the spool and it makes the blowoff louder. i am also running the SPT catback so i can safely assume you would have the same or similar results. Im thinking about modifying my stock airbox like the pics posted by some people in the thread, but my main concern is warranty issues.
 

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I'm running a cold air intake, a catback exhause, a downpipe, and a lightened crank pulley. i drive it like i stole it and haven't had any problems so far. car seems to run smoothly, but i'm not pro at judging that. no CEL so far and the engine is fine.
 

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This is just my experience so take it as you will. I have a UR catted DP, SPT exhaust and a high flow panel filter with no tune. I have had the DP and filter for about 6 months and I run it like a stole it a bit. I have experienced no CEL, I also have a cheap boost guage and it has showed nothing over around 13-15 PSI obviously it isn't an exact number but I haven't had any fuel cutoff from overboost. With the SPT exhaust installed I ran an Auto-X this weekend and ran the hell out of it and didn't have any CEL or overboost effect either. I have no idea what the AFR is in this config but it isn't far enough off to make the computer throw a code. I don't know what would happen if I had an intake. There is a definitely feeling of more HP and torque from the ole butt dyno with no ill affect so far.
not smart at all, especially if you are driving your car like you say you are.

A catback won't throw things off too much, an intake will a little bit (depending on the intake). You might be able to run both without a tune without too much of an issue, but it depends on the intake, and your specific car's temperament. If you insist on running an intake untuned (which I wouldn't suggest personally, but it's not the worst thing in the world), at least equip yourself such that you can read the AFR and see if your ECU is compensating for any knock (you can't always hear it yourself).

A DP is another thing completely, especially if you already have the catback. If you care about your car, do not run a downpipe without some sort of ECU tuning, ESPECIALLY if you don't have anything to monitor AFR, knock, and maybe boost. There are plenty of OBDII gauges out there that will allow you to see these values. Just because you don't see a CEL, or experience any blatant negative effects in a period like 6 months, doesn't mean you aren't causing damage to your engine that may cost you down the line. Things don't always go boom right away.

The bottom line is that cheaping out on this type of stuff so you can save a couple hundred bucks right now has a lot of potential to cost you a LOT more in the long run.
 

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i know it can't be felt, but it hasn't been bad enough to throw a CEL or cause damage. the valves tick a little but it's nothing to worry about i don't think, it's done that since before the mods. my buddy has a turbo RSX and he is running almost no restrictions, he has a little boost creep, said it's nothing to worry about.
 

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to clarify, i'm not running a downpipe, just an stock sized up-pipe. i want more than anything to get AP, but i don't have the money right now, my job is slowing down for the winter. think i'll be fine till march?
 

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to clarify, i'm not running a downpipe, just an stock sized up-pipe. i want more than anything to get AP, but i don't have the money right now, my job is slowing down for the winter. think i'll be fine till march?
If all you have is a CAI and a CBE along with the pulley.
You should be in the upper 12 - low 13 afr range.
This is technically within the upper "safe" limits of the OEM tune. Its the gray area where people want to be on teh safer side and get a tune.
Earlier you stated you had a downpipe, and this would push you into the danger zone.
 

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sweet. good to hear i'm not killing my car. what i meant is that i WANT a downpipe. i suppose that would be over kill though without a tune, thanks for the help.
 
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