Just bought car it has this catch tank. Looks like coolant swirl tank or catch can but the ports for the lines are pretty small. Nothing is hooked up to it.

 

not something that belongs in an fd... its a "catch can" but its unvented. remove it and never think about it again

 

I mean, i can weld aluminium so it can be whatever i want lol if i need to drill and add like an an fitting and vent. Do you run catch cans on rx7?

 

May have been a container for a meth injection set-up.

Stock FD has a breather tube that runs from the oil filler neck down to a nipple in the front turbo air intake elbow.

Often people will reroute the breather tube to an aftermarket catch can.

Issues come up if the oil pan is overfilled with oil and the oil rises to the breather tube.

Some original set-ups have a t in the breather tube that also routes fumes back to the UIM through a check valve..