they will fit in to b16a ,
The manifold are one piece type , from the top header mount to the catalys adapter ,
if this o2 sensor wont fit to your plug , you could use your stock o2 sensor .
im looking for cusco lower arm bar front & rear ver2..yeah i know i can buy it from yahoo japan..but i want to ask first from all if anyone know or have this type of arm bar for sell?