Originally Posted by rcdash

^ most E85 tunes don't change between E70 to E85. I know in my maps, I am "all in" after 70%.

You do not want the check valve as you have described between the driver's side valve cover vent and the turbo air intakes. The turbo air intakes generate the level of vacuum you want during all conditions (low at idle, high vacuum under boost). You want crankcase pressure to be evacuated by the turbo air intakes. In the case of the OP, the passenger side breather provides a source for fresh air ingestion [helps evacuate fuel and water vapor preferentially over the heavier oil vapor] and also as a safety in case the blow by gases are produced in excess of the ability of the turbo air intakes to evacuate (or if the line gets kinked as OP described).

Putting a large catch can in between is a good idea though to trap water and fuel vapor (especially with E85)!

I have both valve covers holes (and the central nipples) all routed to a large catch can and then two large 10 AN hoses going to each turbo intake. It works quite well.