so...is an intake only worth getting for the wrx if the proper engine management is used to keep the compression ratio the same?

 

You have to replace internals to change compression ratio. The intake causes the engine to run too lean, meaning there is too much air for the amount of fuel being injected. This can lead to detonation, which is bad mojo for your motor. They just don't give enough benefit to risk blowing things up.

 

say ur only mod is an intake...there is no other way to stop the risk of detonation besides getting new internals?

 

No. But to put an intake to proper use, you need some form of fuel and spark management. (It has nothing to do with compression ratio). If you have an intake, just sell it or trade it for a pulley or something. The reason for this is, once you have some sort of management system, you will need custom tunes to get max power and reliability with an intake. They are just more trouble, more risk than they are worth. They simply don't add that much power for all the potential problems they cause and the money they cost.

 

Don't take my word for it. Ask an expert. Whoever it is you have seen or heard about that is obviously very good at tuning, ask them. Like I said, none of the well-respected tuners (meaning shops run by people who do individual work, not just people who sell other company's stuff) make cold air intakes for a WRX. Best example is Cobb Tuning- they make hands-down the best intake for the EJ25, but they haven't made one for the WRX. It isn't because they can't, but because they know they shouldn't.

 

so if you were going to upgrade the fuel system then an intake (with proper tuning-UTEC maybe?) would be worth it?

 

I still wouldn't say it's 'worth it.' But no, with proper management you PROBABLY wouldn't get knock. But like I keep saying, the guys who make their living tuning cars, who graduated with mechanical engineering degrees specializing in the internal combustion engine, all decline to put intakes on a WRX. Take that for what you will. If you want one, go get one. But this thread has gone way off topic, and I have said all I will say here about intakes. If anyone else wants to contribute regarding timl's 'backfire' problem, I'll help with that if I can.