John,
If you still have some concerns even after finding out that this chamber feeds into the oil pump, you might give Carleton a call. I think he drilled some holes to drain the oil in the racer, which is something that I have seen done to several hot motors. Obviously, the rate at which it drains cannot be too fast as it is the supply to the heads as mentioned.
I have had a problem with this chamber in the past. I have thought about drilling an oil drain plug so it can be drained. If there is a mechanical failure, like a big end, the chamber fills with metal particles and the best you can hope for is that they pump into the UFM. I installed a spin on filter prior to the UFM. I had another engine that had Castrol R in it and the R went moldy. I changed the oil five times (in quick succession)and the old R was still showing up. I would have thought that it would have cleaned itself much more quickly. The only sure way to clean it is to split the cases.
I should mention that there is a tiny grub screw that is usually staked in position near the oil pump that will drain the chamber, but it is too small to pass debris.
David