Rep Power: 0

I replaced my exhaust in my 01 civic LX, its the es1 sedan with a d17A swap, the people prior to myself of ownership had a protuning labs dna motoring budget exhaust kit put on it that was very old broken and welds and the b pipe was bent and broken. so i got the exhaust same kit.
Well In changing kits I come to find that the new kit was 3 inches longer than the previous and yet they are IDENTICAL but the piping itself was a bit shorter. which wasnt an issue. I cannot find a downpipe test pipe b pipe whatever for it anywhere that isnt discontinued or sold out.
SO TO MY ISSUE. since installed it is VERY RATTLE CANNISH, Raspy almost, but when i accelerate past 4000 rpm in 3rd or accelerate at all in 4th and 5th i get a very deep almost rubbing vibration under my front and passenger seats.
I am assuming since the b-pipe downpipe is bent its making the bend pipe rub and vibrate against the under of my car?
also now I seem to be bogging like if i let off the gas pedal itll like lose power after a second or two. Its never done this before theres only 58k on the motor it was a donor swap because the original had 380k. there is no residue in oil, nothing. My antifreeze reseviour is full and hasnt changed.. Im like super lost. Im changing my spark plugs out tonight and checking my coil packs for corrosion or anything. my intake is clean clean like brand new as is my Cold Air Intake.. Im stumped. lol
Please any opinions or idea. ill take em. It was practically DIRECT change out, same stuff just brand new. and I even checked the header, downpipe connection and all other flange and gasket spots for leaks and there is NOTHING anywhere. i've check three times over and over JUST today alone. lol