i bought a replacement exhaust manifold for my 98 Astra SRI X20XEV from vauxhall as mine had cracked.
ive replaced the manifold, but noticed there are two openings at the top of the manifold that the original didnt have. the original has the pattern for where the holes are but it isnt milled out like the new one. each hole as a threaded hole next to it for something to bolt onto, but i dont know what.
does anyone know of any differences in the emission systems used on different year X20XEVs? prehaps this is for some sort of gas re-circ?