Im currently running a vitara 8v with a standard samurai manifold and exhaust. is there a lot of difference in the bore of the vitara exhaust? eg: would it be worth putting a vitara exhaust on it? i imagine it would probably help it breathe a lot better.
also im going about making my own inlet manifold but i noticed this hole in the head.
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its in the vitara head and the samurai head, but theres no hole in the manifold for it to go into, so what does it do? is it importiant?
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Thanks for the help guys