I have a 2006 Impreza that is not turbocharged. Is it possible to put a turbocharger or supercharger on this engine?

Sure it is. How much are you looking to spend?

 

Cost, Performance, Reliabilty - Pick two.

 

To do it *right* - put about 5 psi into the stock engine - used WRX turbo, intercooler, piping, complete exhaust system, engine cross-member, etc. Bigger injectors, fuel/ignition management, gauges......

 

Probably going to run somewhere around $3,000 to $5,000 depending on what you get and how much you know about building and tuning forced induction engines.

 

It would be cheaper to buy a car that already has one. But if you really want it then there's no reason why you can't turbo it - hell you can turbo your riding mower if you really want to.

 

GD

on the riding mower statement,.. would an old IHI off a 87 GL10 work

on the riding mower statement,.. would an old IHI off a 87 GL10 work

 

If you could get the RPM high enough (look around for B&S performance parts - you probably could), then yes. Probably have the best luck with one of those big v-twin's.

 

There are some riding mower manufacturer's that use Generac 997cc v-twin engines.... you get that sucker up to 10,000 RPM and sure - a VF7 would rock it's world.

 

GD

Back on topic, the 2.5's really don't care for boost... My advice is to either be happy with what you have non turbo and maybe put an exhaust and intake (IIRC they even have an AP for it now) on it, or trade it for a WRX. As far as the 2.5 N/A is concerned, I'm not sure you can spend enough money to make it reliable turbo.