I had to remove my cat cause it was done for, but couldn't afford a new one so put in a test pipe. I read some other posts that say you should gain HP but I swear i lost like 20HP. This is mostly up to 6000 rpm, I'm too embarrased to go higher than that cause my car sounds like a weedwacker with a loudspeaker. My set up is a B18C-gsr in an EK. Is there any back pressure issues that would cause this loss of power? Thanks

 

run a test pipe straight to muffler.. that is plenty of backpressure

 

sounds like its in your head, add a resonator if its to loud