Today, dollar for dollar, is the 318 faster than the 340 ???

Yes that's the same thing Ford did with the Windsor. They figured out how to make horsepower while being emissions compliant. When I think of the LA 318 I think 235 Horsepower, restrictive heads, restrictive exhaust and 2 barrel carb. The Magnum is a different thought all together, it already sounds like the heads are better for example, and that's a big step in the right direction as compared to an LA 318. yes the FI I believe runs cleaner, you dont see sludge in valve covers like a 70s carbed car.
sludge was from the leaded gas , never saw sludge on any of my car that ran unleaded gas