I have an 85 with 12A - I suspect I have a plugged cat(s)! When I hit them with a mallet, there is some loose material inside! The outside shell seems very solid . . . could I open a window in each of the cats, gut them, and weld the window back in? Would the noise level be acceptabe to the cops? Would gutting them damage the engine? Am I missing anything? Would I just be better off putting in a "test pipe"? Could that be left in place permanently? I don't have to worry about emmission testing!
Thanks!!!

 

get a pipe cutter, cut them off, weld in a piece of replacement pipe, lot easier and a lot better

 

A straight pipe won't damage the engine?

 

I went the easy route by buying a bonez racing pipe from RX7.com for my 83 GSL. Lowered the noise down considerably, car felt a bit less bogged down, and it fixed a nice exhaust leak I was having.
Mine was a very easy replacement, just bolted right in place of the stock precat and cat. Looks like the 84-85 models are different though, but I would look into it.

 

Thanks, Guys!
If we ever meet, OK on that beer thing Mike works for, but forget the sex!