Originally Posted by
Marc sierra
How does the oil drain back from the head to the sump on a YB? My BOA has a timing chain where it is completely open where the oil can flow back and it has a drain hose from each head to the sump. But the YB doesn't have a timing chain in oil or a hose back to the sump (as far as I know).
Via a 20mm hole in the rear of head and block.
high performance pinto's back in the day had twin braided lines fitted from head to sump.