After months of talking about updating my oil catch can setup, I finally got around to doing it (with the help of a friend and an experienced welder). In theory, the catch can should never over-fill at the track ever again, and I'll only have to drain it occasionally with street driving.
I kept the same little 'D1 Spec' oil catch can, but the following changes were made:
- We welded a big extra section onto the side of the existing catch can, increasing it's capacity from ~400mL to ~1L.
- We improved the baffling, with a combination of plates and steel wool.
- We added a -8 drain hose from the catch can down to a new fitting welded to the sump.
- The drain hose comes from a 90 degree fitting on the side of the catch can, about a third of the way up from the bottom of the can, so almost nothing will be drained to the sump unless an excessive amount of oil enters the catch can while I'm at the track.
- On the street, the fluid level in the catch can will remain well below the drain to the sump.
- I still have another smaller drain hose from the base of the catch can, which goes down to a manual shut-off valve under the car. This allows me to easily drain anything that collects in the catch can below the level of the drain to the sump.
Next time I go to the track, hopefully the oil catch can mods will prove to be successful!