I've seen A LOT of posts about making HP with a 318-So why is it so ???

Yep, that's why I mentioned above all the parts you need to make a Magnum happen. If you need to buy a intake and carb, ignition and exhaust to make a Magnum work in your car why not just put those pieces on your teen that's already under your hood. Magnums are better but at what cost!

Here’s why I mostly disagree;

It’s that the LA & Magnum as delivered come a certain way.
Most LA engines with 318’s came as a 2bbl.
Converting a Magnum to a carb will require the same parts. The intake prices for a Magnum brand new vary a lot. Not so much for the LA which is generally cheaper as new from Edelbrock or a used unit vs a used Magnum.

So a price comparison can be an extensive writing. Anyone thinking about this should price shop down spend wisely or just throw caution to the wind vs the wallets same and just get the brand spanking new Edelbrock.

But each engine so far just needed a 4bbl. carb and intake. Only brand new OOTB the Magnum costs more from 1! Manufacturer... The knock offs are so cheap that argumentation is crazy and perhaps you need a better job or another hobby.

The price of cylinder heads also falls in like the intakes.
Be it a 318 vs a 360, LA vs a Magnum, stepping up from the OE head is a cost you have to ether price shop for the cheapest or just go out and get the expensive head. Being that the trick flows, which IMO are the best bang for the buck in terms of return performance on the dollar spent while fitting both engines. Being that’s the fact of the head, if I were starting a engine from scratch now, that would be the only head choice I’d consider for the street, street strip machine. By the time you purchase and then port the Edelbrock head, (not doing it yourself) your paying about the same as a trick flow. Of course if the cheaper Edelbrock fits the wallet or build, then that’s fine as well. Choose your parts well.

On camshafts, each need a upgrade for performance unless that whooooping factory rated engine’s HP is good enough.... lmao...

The Magnum can just get away with just a cam purchase on a lot of levels.
The LA can also but also requires lifters with the cam. Still cheaper than just the roller cam but the performance spec vs spec being as close as the same as possible .... makes the HFT a LOOOOOOOOOSER....