[greenmachinedriver]

to anyone else who may read this, do not leave any catalist material at all in the cat. when it breaks up into dust it is extreemly abrasive, and belive it or not the exhaust pulses can push the material back into your engine. you can imagine the bad things that happen next. i know it seems counter-intuitive that it can move the wrong way inside the exhaust but it will, your exhaust valve does not close the instant your piston reaches top dead center on the exhaust stroke. it stays open for a short time as the piston starts its downward travel, couple that with another cylinder on the same bank starting to push out exhaust and you start to get backwards movement through the exhaust. i have seen this happen on bone stock cars that had a cracked or broken catalist, the carnage ranged from ruined piston rings to the engine ingesting its own valves. just somthing for you to think about before you leave those little pices in there.