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I just added on the cold air intake to my new baby with 230miles on it. I noticed with the stock intake the computer reading on the lcd was giving a "peak" psi at 20.4 range give or take....now I notice it at around 19.6 Peak psi. Is this a good thing or bad thing? The WRX is seems to have more beef when turning on and more aggressive during idle and acceleration, plus you can really hear that turbo swhoosh much louder. So the big question is dropping one PSI good or bad...I'm no expert.

Thanks!!:)
 

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What does your tuner say?

Sent from my SM-G960U using Tapatalk
 

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Am I correct? Does the car need a tune if a cold air intake is added? I added one to my 05 wrx and three days later I blew a head gasket. I am unsure and would like to be positive for future reference.
 

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Yes. The car has to be tuned for an intake
 

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Am I correct? Does the car need a tune if a cold air intake is added? I added one to my 05 wrx and three days later I blew a head gasket. I am unsure and would like to be positive for future reference.
It is highly recommended.
 

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Is your car tuned? Like mentioned above. It must be tuned for an intake.
 

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Am I correct? Does the car need a tune if a cold air intake is added? I added one to my 05 wrx and three days later I blew a head gasket. I am unsure and would like to be positive for future reference.
Sometimes you have to do it twice to learn from your mistakes, eh?

Just know that the minute you upload that tune your engine warranty is pretty much gone. Without that permanently stamped alteration to your CPU, you can probably just take the intake off now and keep your warranty on your brand new car. Just something to consider.
 

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It is highly recommended.
I mean, this is true. You don't HAVE to do anything. It is as he said highly recommended. Intakes often mess with the mass airflow sensors reading because the factory calibrates the ECU for the factory airbox and it's airflow. Adding a cold air intake can skew the reading causing rich or lean conditions. Both are harmful in the end although it takes longer for the effects of a rich afr to really take hold but in the end lead to a similar outcome.
 

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I mean, this is true. You don't HAVE to do anything. It is as he said highly recommended. Intakes often mess with the mass airflow sensors reading because the factory calibrates the ECU for the factory airbox and it's airflow. Adding a cold air intake can skew the reading causing rich or lean conditions. Both are harmful in the end although it takes longer for the effects of a rich afr to really take hold but in the end lead to a similar outcome.
Honestly, even the intakes that are DESIGNED with air straighteners and an OTS map (e.g. Cobb SF intake) I find somewhat questionable.

I'm by no means an expert, but from personal experience I've found that:
1. The slight restriction of an OEM airbox acts as a "negative Plenum" in that it is a buffer to smooth airflow across the MAF housing
2. I've noticed that the intake charge temp swings wildly with an aftermarket intake/intake box -- I think aftermarket intakes aren't as well insulated against engine bay temps, but the airbox facilitates easy ingestion of cold air from the fender, so you will see IATs more than 40 degrees F over ambient at stop, dropping to 10 degrees F over ambient within 1 minute of reaching highway speeds. This really puts a lot of pressure on good IAT compensations.
3. EVEN with the air straighteners and airbox, I'm still getting variable fuel trims at different MAF during cruise. I question if even the Cobb SF intake (which does have reasonable R&D behind it) has turbulence zones at cruise airflow. Imagine what that's like with an intake that isn't properly R&D'd.

All these things can be easily addressed with custom ECU calibration. At this point, I don't yet have a WBO2 sensor so I can only take shots in the dark so to speak. Definitely wouldn't recommend an intake to someone that is not planning on a custom ECU calibration.
 

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Get a tune. Did you follow in the intake install instructions? Most aftermarket intakes require you to remove the turbo restrictor pill.
 

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Get a tune. Did you follow in the intake install instructions? Most aftermarket intakes require you to remove the turbo restrictor pill.
I have never heard of an aftermarket FA20DIT intake requiring you to remove the restrictor pill. Stage 1 tunes should not require that. That is only needed when going stage 2 with a new j-pipe and tune.
 
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