Okay my next big question: to intercooler or not to intercooler?

Remember, this is going in a "hot rod" ('29 Tudor Sedan). I will not run an air-to-air i/c on this car. I am considering a PWR barrel water-to-air i/c that'll mount ahead of the engine and behind the radiator. A small heat exchanger should fit nicely ahead of the radiator which will be covered by a '32 grille shell.

If I've looked at the compressor map for my desired turbo correctly, I should be operating at max output efficiency at full boost (15 psi). Do I really need to go with an intecooler at all? I really like the idea of running an i/c and I think it'll be beneficial on warm/hot days but it does add significant cost to my build.

So what do you guys think?