hey guys, currently im running just I/H/E on my civic and ive got a turbo kit going on this spring. right now my cat is welded to my header so that will go when the header goes. the downpipe on my turbo has the stock cat flange on it so i can easily put a cat in after the dpipe. my question is, what would be the result of not using any cat and just putting a straight pipe in there. i have full 2.5 inch mandrel exhaust with a resonator and high flow ebay cat as of now.

 

It smelled like complete *** in my civic. I've also seen dyno graphs where stock cat vs. test pipe only gained 4-5 HP.