Breather box/system on high rpm engine?

[Fiatdude]

I've found the tired and true practice of having one crankcase vent and then venting both valve covers -- the drain goes back into the 1-2 valve cover -- This has worked for both NA and boosted VW engines up 2990 cc's

The only thing that needs to be addressed is the size of the box.... My friends 2442 High Compression Super Street engine consistently fills a 2 quart, he went up to a 3 quart and the problem was fixed