I replaced the O2 sensor in my 87 non-turbo Sundance, and while under the car, I noticed the stove has rotted out (I've since plugged off the vacuum lines on the airbox, as the inlet flap now does nothing).
I'm curious about what the options are for the stove hole in the exhaust manifold. If I blocked it off, would it make the engine a little quieter? This poor old engine is a little loud, and I'd like to quieten it a bit. Would blocking it off raise my emission levels, or negatively impact the engine or exhaust systems?