The issue yo uneed to be concerned with when using a B1 head is getting the oil back to the pan. Especially if you are running a vacuum pump, that is going to fight getting the oil back n the pan. IMO the bigger you can make those drainback lines the better off you will be. Oil control n a BBM is always gong to be an issue. I see most bandaid that buy running a huge quantity of oil, which works but does not cure the problem. It is just inherent with the design. Better pans, scrapers etc all help.
This. I was running -8 drainbacks lines from the front & back of the heads to the pan, and the pan was a custom pan with a lot going on inside, but can't remember the name of the vendor, but it wasn't cheap. At the time I was running Moroso's big enhanced 4-vane vac pump. Drainback was not an issue. Chuck put the regulator in the custom valley tray, and everything worked great.
