I have four cats on my truck and if I ran no muffler would there be enough back pressure for the engine so it wont hurt it?

 

That should work fine. I would recommend using 21/4 in tubing though to retain some backpressure/torque. I have only 2 cats and true duals with an x-pipe on my 2005 screw running 21/4 inch piping. i have it exiting lighning style too, and i love the sound! The backpressure seems to be fine IMO. It definately feels like i gained power so you should be fine...

 

ok sounds good thanks for the help. O is the stock pipe diameter 2 1/4

 

On my 97 stock piping was 2.5" I left all my original cats on and just removed the stock muffler. BP test showed a very low but sufficent amount. And it definetly made the truck wake up.

 

O Hell yea I need a lil somthin now since i got some new 35s Mud Grapplers!