intercooler sizing
 

I was just wondering if there is a way to calculate how much intercooler will be sufficient or most beneficial. I know if your intercooler is too small, then its not good. But can there be any problems if your intercooler is too big for your turbo set up?

Yes it will slow down how fast boost reaches the manifold because there will be a lot more air space to fill, a turbos CFM is a huge factor when selecting an intercooler.