273! 5.2/5.9 Magnum!
Okay, I got that out of my system.
Irrelevant question, since you didn't bother to post an intended use.
You must be intending to build stock stroke motors, since if you're building a stroker the factory displacement doesn't matter one iota.
So as far as stock displacement goes, go 340 if you want to spin some R's, 360 for a solid torquey street motor.
And yeah, for all the flamers out there I'm well aware that a 360 can be built to turn some good rpms; but for a given build, a 340 will most always spin higher. And likewise on similar builds, the 360 will generate better torque numbers.
Decide on your purpose, then decide on your engine.
And these days, the choice will hinge on what you can get that's still in buildable shape..
