i bought a tdi mk4 golf that an idiot had modified to be straight pipe all the way out
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so i'm looking at needing to install a catalytic converter and muffler.
any recommendations for what type of cat works best with our engines?
Most other tdi forums are full of folks talking about cat deletes and mufflrectomies...
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... i know the ecomodder crowd is into efficiency, so here's hoping someone has some bright ideas about the best cat for an mk4 tdi.
thanks for your knowledge!