It's not the size of the motor that will designate how large of an intercooler you need. It's how much cfm you're flowing through it.

Yes you can have too large of an intercooler, no that one probably isn't that much of overkill. Unless it's 3" thick. Either way, it looks like it will cool fairly well, and flow a good amount of air. Reminds me of the larger NPR intercoolers.