Harbor Freight DC design questions

[Manns50]

Deciding which way to go on a build. Originally was going to do a 4" 90 elbow for inlet  and a 4" straight outlet into blower intake. Not a top hat design just recessed in a barrel. But started seeing several discussions of having inlet as straight as possible.
Started thinking about using the metal ring with the somewhat cone disc that comes with the Harbor Freight DC on top of the barrel as in a top hat design. Have seen a few done that way and since it has the inlet coming in on the side would eliminate the inlet elbow.
I also would think that cone disc that's in there might help retain rotation longer.... Am I right? The cone disc being the top part of the baffle with an added sheet of plywood over it?
I guess my main question is how important is it to Not have an elbow as an inlet on the top Of a separator?

[Manns50]

Bueller? Bueller? Anyone? Lol

[tommitytomtom]

I'm working on a 55 gallon drum separator using a Reliant 3hp 2 bagger. I removed  on of the inlet welded to one of the rings where one set of filter/collectors mount. Basically using it as my straight side inlet to a topcoat design. Check out my thread soon.

[Manns50]

Awesome pics would be great

[tommitytomtom]

I posted on a new thread. Didn't want to hijack yours.