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Old 08-29-2013, 07:57 PM   #1
Ray-Ray03
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Default To intake or stay with stock airbox

I am currently running Stage2 HWG with an Invidia Q300 TBE and K&N drop in filter in my 2012 WRX hatch. I have read many negative posts about the drop in. I ran a datalog from 2K to 7K RPM's. I sent the report to Cobb and they wrote me back saying how my datalog looks real strong and healthy and how the K&N drop in is either a hit or miss, in my case it is a hit. Now, the dilemma is whether or not I should keep what I have since it is running great or go with an after market intake.
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Old 08-29-2013, 07:59 PM   #2
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Keep it like it is if its running strong. Stock box is good just dont over oil it.
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Old 08-29-2013, 09:35 PM   #3
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keep it at your power level.
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Old 08-29-2013, 09:38 PM   #4
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Your intake is fine, any research would show you that. But we can tell you didn't do that part.
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Old 08-29-2013, 09:42 PM   #5
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Quote:
Originally Posted by HinshawWRX View Post
Your intake is fine, any research would show you that. But we can tell you didn't do that part.
This is what is wrong with Nasioc. This guy just wants an opinion. There is no need for a response like that. If you can't say anything nice...
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Old 08-29-2013, 09:47 PM   #6
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Quote:
Originally Posted by jerbull88 View Post
This is what is wrong with Nasioc. This guy just wants an opinion. There is no need for a response like that. If you can't say anything nice...
This isn't the nice forum AND there is a sticky thread at the top of this forum that speaks of this very issue which the OP failed to read...404 horrific fault not found.
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Old 08-29-2013, 09:50 PM   #7
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the sticky contains facts. he was asking for opinions.
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Old 08-29-2013, 10:08 PM   #8
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Well..... This turned into something I didn't expect. I'll figure it out on my own. Thanks anyway.
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Old 08-29-2013, 11:04 PM   #9
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I love the Cobb intake. Makes the car sound great.
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Old 08-29-2013, 11:09 PM   #10
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Quote:
Originally Posted by Chrisf4i View Post
I love the Cobb intake. Makes the car sound great.
That's about all they're good for...with stock turbos
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Old 08-30-2013, 12:30 AM   #11
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The stock air box is the best engineered part of the entire intake system.
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Old 08-30-2013, 08:27 AM   #12
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I had the Cobb intake - sounds amazing, but I switched to the AEM CAI for some lower intake temps. Not quite as loud as the Cobb, but still sounds good. If you get a protune there will be some sort of gains with an intake, how much? Not sure. But it's something if that makes you feel any better that it's not a complete waste.
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Old 08-30-2013, 09:22 AM   #13
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Quote:
Originally Posted by Wrexflex View Post
I had the Cobb intake - sounds amazing, but I switched to the AEM CAI for some lower intake temps. Not quite as loud as the Cobb, but still sounds good. If you get a protune there will be some sort of gains with an intake, how much? Not sure. But it's something if that makes you feel any better that it's not a complete waste.
You should get a pro tune for an intake anyway so the maf scaling is correct.
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Old 08-30-2013, 09:40 AM   #14
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Really JonnyV????
Saying a protune will probably see more gains versus his OTS stage 2 map... I was assuming he knew he had to switch from his stock intake map to Cobb SF map.
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Old 08-30-2013, 12:28 PM   #15
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Quote:
Originally Posted by Wrexflex View Post
Really JonnyV????
Saying a protune will probably see more gains versus his OTS stage 2 map... I was assuming he knew he had to switch from his stock intake map to Cobb SF map.
OTS maps are a safe average. Just like his k&n drop in, it may not perfect, it's hit or miss.
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Old 08-30-2013, 12:39 PM   #16
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"the stock intake is great" is, IMO, one of the biggest wive's tales on here. With a VF on my 07, switching to an AEM CAI gave noticeable gains. Car spooled more readily, making more torque everywhere. The tuner stated that the later model intakes are even more restrictive, meaning there are more gains to be had.

Tuner also was emphatic that intakes must be tuned for, so either get protuned, or use a map specifically made for the particular intake you choose.

And don't cry about how you should only run a CAI if you live in a desert for fear of hydrolocking, if you don't drive through foot-deep puddles you will be fine. Course it never rains where I live, in Seattle.
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Old 08-30-2013, 12:43 PM   #17
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Quote:
Originally Posted by JonnyV2889 View Post
That's about all they're good for...with stock turbos
unless you want 15 whp or so with better spool, then yeah.
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Old 08-30-2013, 01:57 PM   #18
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My 2011 wrx stage 2 have the aem cold air intake with protuned! The car runs much better that the oem intake. My afr at wot is 10.3 10.4 ( safe ) 0 knocks and everything perfect.

Process west tmic
Synapse diverter valve
Aem cai
Tsudo bellmouth downpipe
Invidia n1 dual
Protuned 19 - 20 psi.

The difference with oem stock air vs aem cai with protuned is huge.
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Old 08-30-2013, 02:27 PM   #19
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Well with that year WRX Cobb says you def need a tune. Says in big red lettering right below the intake on their site. That is where you will see the gains with an intake, with a tune that is.
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Old 08-30-2013, 02:39 PM   #20
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I still think on turbocharged engines the gains from a CAI are extremely minimal or non existent in comparison to an SF intake.... Ok let's say you have a 10 deg difference in IAT... Once that air passes through the turbo I would bet that difference is even less.... I have not found any data that proves this wrong or right, but for those that have dealt with compressing and releasing gases know how quick and powerful the temperature change is... This temp difference post turbo will have such a minimal impact on power output with how hot the air is to begin with... This is why IC's are your workhorse for cooling... Now once you get into the heavily modified area and are trying to squeeze everything you can out then this would make a difference but in reference to typical Stage 2+ cars the dif is negligible....

If this weren't the case then I bet Cobb would have made a CAI....
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Old 08-30-2013, 04:30 PM   #21
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Quote:
Originally Posted by TheWRXinMe View Post
I still think on turbocharged engines the gains from a CAI are extremely minimal or non existent in comparison to an SF intake.... Ok let's say you have a 10 deg difference in IAT... Once that air passes through the turbo I would bet that difference is even less.... I have not found any data that proves this wrong or right, but for those that have dealt with compressing and releasing gases know how quick and powerful the temperature change is... This temp difference post turbo will have such a minimal impact on power output with how hot the air is to begin with... This is why IC's are your workhorse for cooling... Now once you get into the heavily modified area and are trying to squeeze everything you can out then this would make a difference but in reference to typical Stage 2+ cars the dif is negligible....

If this weren't the case then I bet Cobb would have made a CAI....
The thing is, there usually isn't a 10 degree difference between a hot air intake like the SF and any cold air intake or stock airbox... more like 50-100 degrees in stop and go traffic. Hotter air coming in is never a good thing. Colder air is always better.
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Old 08-30-2013, 11:58 PM   #22
spintheground
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Quote:
Originally Posted by northman View Post
"the stock intake is great" is, IMO, one of the biggest wive's tales on here. With a VF on my 07, switching to an AEM CAI gave noticeable gains. Car spooled more readily, making more torque everywhere. The tuner stated that the later model intakes are even more restrictive, meaning there are more gains to be had.

Tuner also was emphatic that intakes must be tuned for, so either get protuned, or use a map specifically made for the particular intake you choose.

And don't cry about how you should only run a CAI if you live in a desert for fear of hydrolocking, if you don't drive through foot-deep puddles you will be fine. Course it never rains where I live, in Seattle.
It is great.

A lot of people jump on the, "Don't get an intake!!" Bandwagon because of the known issues running one without a tune. Some thought on that as well, the ECU has an easier time learning with the stock airbox during weather / temperature change and altitude change. Some say it's able to interpolate with the OEM box where as a CAI you may need a winter tune.

Also, the thought process of flow restrictions being the only reason to upgrade, IE maxed out MAF. That won't happen on a stock turbo WRX (08 and below at least).

With all that said, the stock airbox IS a great intake. There is data proving that a short ram will actually net you less power IIRC it was back to back dyno pulls with SPT SRI and the stock box but I recall seeing something along the same lines with the Cobb intake but I definitely could be mistaken.

Considering the nature of most of the import scene it is understandable to have the intake issue be something you research before you buy. A honda will benefit from a K&N autozone intake without question. Applying that mentality to FI Subarus is fool hearted.

Does it make sense for OP to spend $150-$300 on an intake and $400 on a protune? No.
The cost to gain ratio is no where near logical and that money is better spent elsewhere.

OP - In the end, it's your car and money so do with it what you want.
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Old 08-31-2013, 12:14 AM   #23
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Quote:
Originally Posted by TheWRXinMe View Post
I still think on turbocharged engines the gains from a CAI are extremely minimal or non existent in comparison to an SF intake.... Ok let's say you have a 10 deg difference in IAT... Once that air passes through the turbo I would bet that difference is even less.... I have not found any data that proves this wrong or right, but for those that have dealt with compressing and releasing gases know how quick and powerful the temperature change is... This temp difference post turbo will have such a minimal impact on power output with how hot the air is to begin with... This is why IC's are your workhorse for cooling... Now once you get into the heavily modified area and are trying to squeeze everything you can out then this would make a difference but in reference to typical Stage 2+ cars the dif is negligible....

If this weren't the case then I bet Cobb would have made a CAI....
You're missing the biggest problem with a SRI...

1) 10 deg difference is laughable, as FCmaniac said it's easily 5 times that.

2) Yes, the intercooler will cool things back off, but the IAT sensor is located before the turbo. The IAT sensor is what tells the ECU that the temps are too high and corrections are needed. With the INCREDIBLY high IATs caused by a SRI, the ECU is in a near-constant state of high temp correction. It's dumping in fuel and pulling timing when it reads these high IATs, and THAT is what kills power.

Last edited by the suicidal eggroll; 08-31-2013 at 12:42 AM.
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Old 08-31-2013, 01:09 AM   #24
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Such a well thought out position for the intake air temp sensor

A three sensor setup makes the most sense IMO. Pre-turbo, pre-intercooler and post intercooler. Cutting costs for a production car I can understand eliminating the pre-intercooler sensor but that's it.
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Old 08-31-2013, 10:35 PM   #25
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Just tweak your Iat comp tables to have no impact on timing changes if your sure the charge is cooled off enough from the FMIC before the throttle body gets ahold of it or theres gonna be some knock goin on. If the Iat says 200 and really you are sucking 100 degree air per your intercooling method, then this is something you could consider. This works great when you can view pre and post air temps. I see 150 Iat stop and go traffic in Mississippi.......actual temp before throttle body is NEVER above ambient temp per the Dr525 Fmic im runnin. Really cold in the winter too, like 100 Iat and 45 actual charge temps.
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