I have one cooler in the pressure loop and two in series in the scavenge loop. All runs are dash 12.
Be sure that any air will be scavenged from the coolers in normal cruise. So a big dose cannot be saved up and dumped into the engine at one time. Oil out at the top of the cooler.
Cold startup may have the front relief opening, or worse, may pop the case to iron "O" ring.
If you have not built up the engine yet, I would eliminate that junction. And have minimum drag from hose size.
Lynn E. Hanover
Lynn,
This is a little late but after rereading your answer to Bob Mears I wondered how
you would eliminate the front relief valve opening and case to iron "O" ring ??
Kelly Troyer