I have an 88 NA That I recently picked up for $500

It came stripped and without an exhaust.

I just went to the muffler shop today and on my way home it got red HOT!

They removed it at the exit of the cat... the cat was destroyed (new)
The entry to the cat was ok and the pipe was new looking but all the pipes trailing the cat were black!

He blew air through where he cut it off (the cat) and air was restricted at the end of the tailpipe....

I need to know if the car could have caused this in some way.... or was it just a case of a faulty new muffler?

 

rotary engines run HOT. your "new" cat sounds like it was clogged. and it sounds like your running rich as hell and have a leak.

 

how would i know if im running rich?
and why?