Is my swirl pot design okay?
 

I'm planning on building a swirl pot to mount next to the ABS unit. This will double as my new coolant fill location as well. Most of the pictures I see of swirl pots don't have the integrated filler neck, but instead have a nipple leading to a separate expansion tank which then leads to a reservoir. Would combining the two together have a negative effect? This is my design plan so far, any thoughts?

https://www.miataturbo.net/attachmen...ine=1443641967

Was this just a dumb question and the design isn't that big of a deal?

I'm not even sure why you need it so I can't comment on merit of design.

Right now my radiator isn't the highest point in the system. I'd like to ensure that I am removing all of the air from the system. I already have all the materials to make it. I was just looking to make sure it wasn't flawed before I went ahead and started cutting materials.

sure, looks fine. Maybe, maybe you wont get the full deaeration benefits from the swirl pot because your connection to the expansion tank can only happen when the system pressure is over a certain amount.

why not making your swirl pot also a expansion tank

Size would be my guess. We typically expect the expansion tank to have a fairly large capacity.

That said, you can buy little inline adapters from racing shops which have two radiator hose fittings and a cap / overflow line. Not a swirl pot, but an easy way to put fill / bleed at the highest point.

You could pick up to fill the system and make sure there is no air in it, or one of the magic funnels.

That's what I am trying to do with this design. Should I do something differently?

I'm using a 7" tall section of 4"OD aluminum pipe for the core. So capacity should be around 48oz. I thought of just using an inline fill cap like you mentioned but if I can make something better, then why not?

I have and use one of those radiator funnel kits and the cost of the airlift just isn't justified now that I don't work on cars for a living anymore.

I have all of the materials already just laying around, leftovers from other projects. It's just a matter of welding it all up.

Since it would be my new fill point wouldn't I be able to achieve most of this at time of fill when using a radiator funnel and bringing the system to operating temp and letting it "burp"?

No, the real benefit of the swirl pot is to get aeration out that happens in a properly bled system, due to cavitation and such.