Originally posted by MystiqueSVT:
I can tell you one thing.....the performance of my car is not hindered. If you'd like to use common sense and not theory on this one......take a good look at the actual ceramic that makes up the Cat. The Contour pre-cats are roughly 6 inches long and about 3 inches in diameter. The actual space that the exhaust gases pass through are no wider than 1/16th of an inch square. Now...this would mean a 6 inch bottleneck of 1/16 of an inch.
Do the math. If these are removed how could they possibly restrict/disrupt airflow more than them being there??? 
Because that hollowed cat isn't a straight pipe. The area opens and closes up again causing the air flow to be disrupted. A straight pipe would be good, but a hollowed cat will not be much better than a fully functioning cat. I cats honeycomb straightens the air out as it enters the cat.
