so? how many?

 

run a single brake line check valve( the big ones) should be more than anuff,dont bother with fish tank check valves.

 

I am running three METAL fish tank check valves and was fine up to 9psi with no CEL.

 

I pefer brake line check valve's cause u only need 1 and its alot cleaner in the engine bay.Ive ran 17psi without a cel (wastgate problem)

 

I got a q about brake line check valves,this is a pic of where it is on a 92-95 civic.Most cars have it there which u can pocket from any junkyard.To test just blow in each side the side that lets out air is the side that wont be connected ,or is the exit .The other side will be connected to the vacaum line