Okay, I have my Apex'i twin chamber blow off valvle installed. I have read the instruction a hundred times but they are vague to say the least. It says for high boost tighten the the spring, how tight do I go. Is it just by trial and error the setting until you get it to vent into the atmosphere? BTW turbo 6 port is almost done, fine tuning is all thats left, went for a little test drive yesterday and saw 11psi in 1st.

 

You want it set as loose as possible without leaking under boost, and yes, it is trial and error.