Civic EG

hi guys i have a d16z6(late models)
for this engine im planning turbo
i want to make about 250-270 hp
i have some questions about some parts
what size of turbo i must buy?(can i use a oem used turbine?)
can i use vitara pistons?
for this goal i must use a blockquard?

I see you have already started a similar thread about this topic: http://civic-eg.com/viewtopic.php?p=307850
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