So I was looking at my exhaust noticing how microscopic the tube from the y through the cat and to the muffler is. I am wanting to fab up some 3.5 inch exhaust from the Y back. Actually, I just want to use the exhaust off of my totaled diesel. It looks like there is a smog pump? and the tubes go back to the catalytic converter? Can all this be removed? what do people do when they put aftermarket exhaust on these things? I don't have to worry about emissions testing. Whats the typical protocol and what effect does it have on the engine? Damn near anything looks like it would help the exhaust on these things.

 

I just crimped the air line running to the cat when I upgraded y pipes and high flow cat. At some point I will remove the rest of the smog stuff but ,cross that bridge when I get there.

 

So it looks like there is one vac line running to the valve on top of the passenger side valve cover. For all intents and purposes, can I just cap that vac line, remove all the tubes and pump, get the shorter belt and carry on?

 

Yes you can