Carburetor cfm calculator

I'm sure that most on here know what I'm wanting to do with the car I get. From what I've read, if I go from a 2 barrel to a 4 barrel that the edelbrock performer intake wouldn't be worth the effort. Also, the rpm's that my engine would be operating in most of the time wouldn't a 600 cfm be plenty for a 318? Cylinder heads, doesn't the smaller ports make good power in the low to midrange area? Would cylinder heads with 170cc intake runner's be to big for a mild 318 or are they okay? Cam, single or dual pattern grind? I'm wanting good throttle response and acceleration with good torque in the low to midrange. I'm not worried about doing major upgrades later as I'm 62 years old and don't care about racing anymore. I'm wanting a cruiser that's fun to drive and has a little extra zip. When I first said that it's a budget build, I do have amount planned for the car and engine modifications, gears, and a good exhaust system. If the cylinder heads wouldn't be cost effective to get them redone, then what would be a good choice for a set of heads? I figured that I could build a engine whether it's a 318 or a 360 to perform well from off idle to around 5,000 rpm's. I appreciate all the help, advice etc, but I truly don't think that I need tunnel ram or a blower to reach my goal.