3.23 or 3.55 Behind a 318

Unless you are mandated to a certain Cu.in. level as in racing, Why would you want to build a 365 over a 408?
Or in the case of a 318, why would you want a 349 over 390?
Building a 318/349 isn’t cheap or easy. Building 318/390 is easy, ordering the kit is pressing a button easy.

Building a 360 or 400+ is dealers choice with the 360 being cheaper, part selection dependent.

A properly built and set up 360 can burn the rubber and be very quick. It is not a slouch.

You don’t need 400+ cubes.
But you want 400+ cubes.

Bottom line, build what you want. Don’t look back. Enjoy!