Or would I need to get a blow off valve?
No, a cold air intake will not help at all, and you can NOT put a blow off valve on a VW turbo with a waste gate. Gasoline ices up inside the intake manifold, so you want to preheat the air a little, to help the gas vaporize. It is true cold air intake compress the air a little, but that throws the fuel injection off and you lose power. And the mass air senor is before what you could put a blow off valve at the throttle, so then the fuel injection has measured that air and is going to match it with gasoline. If you then dump that air out the blow off valve, that gasoline is still going to be injected, so the mixture will be way too rich, wasting gas and clogging the catalytic converter. You don't need or want a blow off valve when you have a waste gate instead, as VW does.
