wouldn't know about USA downpipes etc... not familiar with them
intake piping.. only real way is custom, but they still can make power before they kill the engine
i'd love to see your stock bov
the 1g didn't come with one
yep richness & stumbling happens but you can get adjustable bov's which can help with this altho not eliminate it
if you have a 1ggte you don't have EGR
so does that save some money