I have an 86 951 and it was dead do to the extreme negative degree temperatures. I got it started today but blew and awful cloud of black smoke and black ash all over the ground. It has been blowing black smoke since I have put the new exhaust on. It never blew black with the factory system. Should this be something to look at?

 

It's probably just some loose carbon deposits that were freed when the new one was installed. Did you get rid of the cat? If so i would (maybe) expect this, otherwise i think that it should clear up shortly.

BTW: what does your car look like? I often notice ones that are from my area. ( i live just east of Columbus, but often frequent the Washington Courthouse area)

 

Wait a few hundred miles to let the pipes get situated, blown through, and "normalized." If it still does it, then look more into it.