98 Devil, 93 Deville, 84 Cuttylac built 350 olds, Arctic Cat
After I give the Northstar WOT I get a bad sulfur smell in the cabin. I recently installed a cheap magnaflow direct fit catylitic converter because the other one made a funny noise like it was clogged. car had new plugs, wires and fuel system cleaning with about 2 months ago. What could be causing this?