I drove my '67 fastback around 100 miles today. My lungs hurt and I'm short of breath. The car is a little rich, not a lot rich 331 with 343 rwhp. YES I know cat's didn't come out untill '76 however I want to run them on my 'stang is there anyway? yes I understand that I'll loose a couple of hp. it's better than a few years off of my life. how long will cats live with out a pump?