I do not agree. He allready has the 318 engine and getting a 360 is a loss of money and you only have a dead stock 360 and a lighter wallet. So $50 difference it is not.
Well, I said dollars/hp the 318 is a bad deal, not that you couldn't build the 318 cheaper if you already have a 318.
OK, so what does a core 360 engine cost? $300?
So, build a 318 and a 360 very similarly (rings, bore, bearings, hone, equalize, etc).
Now try to get the 318 to make the same horsepower and torque as the 360 for the price difference ($300). Short of a used nitrous kit, it ain't gonna happen.
If you're going to build a hot-rod motor and sweat $300, you're not going to be happy when you're done.