Will a hollowed out catalytic converter make less performance?

[Mobilesport]

I wanted to get a off road Y pipe for my 1996 Chevy express van but they don't make em for my model

http://img823.imageshack.us/img823/8740/ypipe.jpg (http://imageshack.us/photo/my-images/823/ypipe.jpg/)

[jamesphilo30]

it's a waste of time to hallow them out. The power you get from removing them will not show up to the wheels for the most part. If you have to just weld pipe in place of them

[Mobilesport]

I had to hollow mine out because it was clogged , At this time I'm concerned about the velocity .
What i really need to know is do i need to weld a straight pipe to where the cat is at or is the hollowed cat acting as a straight pipe?
Thanks

[jamesphilo30]

the cat is just working as a tiny muffler. it is not hurting much as it is. if you want to be technical then yes there is turbulence called by exhaust expansion and re compression. so yes for best performance replace whole cat with pipe.