New to V8's. 340 or 383?

This is way I see the engine set up in cubic inch form. All for which can be used in the car differently and quite well.

318's make excellent grocery getters for sure with very good mileage, but, they can also get going real well if built right. It'll take more effort to go fast with a 318. But it is possible to get it screaming.

340's are fine for street & probably the best for racing. Also being a short stroke engine, you'll rely on RPM for power that hangs in there at high RPM levels.
340's are a little more expensive to build. Not to mention you still have to purchase one.

360; the longer stroke engine provides a bit more torque in the small block family than the others . Power peaks a few hundred RPM's earlier. This means you shift earlier.
They make great street, street/strip engines at a cheaper price than a 340.

383; the underrated street warrior hero of yesteryear where they were the front linemen fitted into nearly everything MoPar offered to drive. There very much like a 340 being a short stroke big bore engine. The beauty of the 383 (or the 400 if you fix the low compression issue) is they can really rev high, have bigger ports and valves that can no be fitted into a 340.

The 440 is like the 360 vs. 340 comparison. Just at 57 cubes instead of 20, there is a huge gain by going with a 440.

There is also a good reason for going with a big block besides mad cubic inches over a small block. They can be made light as a small block. Nose heavy? no, not really if you exploite what could be done. But the big catch is expenditure. It'll cost ya plenty over staying with a small block. If your wallet is a limiting factor, there's nothing wrong with a 318. They can be made to go and go quick.