A little while back I saw a vid. Tex post on a catch can which had a drain valve on it, and mine did not. I thought "what a great idea"! So I installed one on mine and I also installed a 3/8's drain hose I ran down and out next to the rad.over flow. I had a chance to use it the other day! And I must say what a good thing, open the valve put a paper cup on the ground and done, much easier than taking the cup off to dran than reinstall.
I'm putting this out there for all with oil catch cans that don't have a valve, I wouldn't : have thought of one had I not seen the vid, so maybe this might help someone else!!