I‘ve heard it is bad to instal a cold air intake on a Subaru wrx without running any form of engine management is this true? I was considering putting a cold air intake on my 2006 Subaru wrx, but I don‘t have any form of engine management and I am worried It would ruin my car.
No. Reputable air intake companies will tell you if engine management is needed with their air intake. Your car will run fine without additional modifications if you use a KN or AEM air intake. KN shows their testing on a 2.0L engine gained 15HP with their intake. That's a good gain from just an intake. You shouldn't have any check engine light problems. If you do you can return the intake for a full refund so there's no risk. It looks like the OEM intake left quite a bit of power on the table for other intakes to release.
1) It's not horrible, but it can lean out your car because the MAF sensor relies on proper diameter and flow characteristics provided by the stock intake. Leaning out bad. It can be fixed by rescaling the MAF sensor. 2) Your car already has a cold air intake. Notice the duct that channels air into the airbox. The design of the intake is already very efficient and on Legacy GTs has been shown to be able to provide air for an engine producing 300WHP, give or take.
