Exhaust diameters and bends

Could someone explain how different exhaust diameters, bends, and x,y,h pipes affect engines? And the differences between how different exhausts affect supercharged, turbocharged, and naturally aspirated engines. From what i have heard is that you don't want to go too big for supercharged engines, but turbo you do.

Here's some info on that subject: https://rivperformance.editboard.com/t2258-the-exhaust-thread

Your question is extremely open ended and would pretty much take a book length of explanation to answer.

To address the last point, though, when you say "big", what are you referring to? - the general pipe diameter of the exhaust system?
I don't think it's accurate to say a turbo should have no limit on exhaust area versus a supercharged engine. If it's a turbo we're talking about, I would say you can be pretty dead on just using the size of the turbo and horsepower as main factors to figure out necessary exhaust CFM and dynamics since the turbo is literally part of the exhaust system and has inherent capacities. A supercharged engine should have something that looks like an N/A engine except with enough CFM capacity to account for the much bigger effective displacement due to boost. If you're really thinking about exhaust restriction vs flow, a supercharged engine like this will probably make its best effort horsepower with virtually zero restriction like an open-header situation.

The exhaust is a very simple system that will become very complicated if you try to re-engineer it too much. I would try to keep it case-for-case and look at what other people are using to support their setups, especially for relatively unpopular supercharged setups like the 3800.