Loochy88

iTrader: (2)

I've been noticing for a while a rattle coming from my exhaust on my 99 Z. I first thought it was a heat shield hitting my hooker catback exhaust. Ive checked every inch of the exhaust multiple times. I finally thought i had it narrowed down to the joint between the ypipe and the ipipe. I bought a nice 3 inch stainless band clamp and tore off the stock clamp and tightened it up perfectly. Unfortunately, it still has the same noise. It rattles most noticeably as you let off a rev at idle. If you hit the exhaust from underneath it rattles, but i cant pinpoint it. It seems like its just coming from everywhere up towards the ypipe.

Is there anything else it cold possibly be. I crimped those little rings on the o2 sensors down cause i thought they may be rattling, so its not them either.

My questions are:

1 About how much would it be if i just took it to a shop and said replace my cats and clean out my ypipe (im afraid cat bits or maybe the screen may be shoved back in there somewhere)

2 Would it be cheaper to just delete the cats by buying an ORY? What options are there for the 99 style ypipe (as opposed to the 02 style).

3 Is there anything else I am missing that this noise could be? Is there any way to test for a rattling cat besides removing the ypipe?

snake charmer

iTrader: (118)

1. A shop would charge you a lot of money . Enough to have pretty much whatever aftermaket /performance exhaust .

2. Yes it would be cheaper . You can mail your computer for what is called a mail order tunethat should take only a weekdowntime forthem todelet the 02s and do whatever other tuning . This alone will net you more power withthe addition in flowwhich is also one of the first steps in mods on your ls1 .

3.Could be bushings or something . Every car ratttles after time jsutone ofthose things . You could replace all thebushings ( prothane makes a kit ) though it does take time.

My advice just go ahead and put a good exhaust system and it will sound well enough for you to forget about whatever soubnd is bothering you .

bmax

iTrader: (1)

My 99 formula did the same thing, so I put American racing headers and catted y with a hooker cat back.
Sounds much better now.

Brad

Loochy88

iTrader: (2)

Suspension bushing (not exhaust hanger bushings)? Its not that since it does it without the car moving.

Besides the bassani ORY, what other options are there for a the 99 style cat setup, that would connect to stock style manifolds?

98dropta

iTrader: (10)

the honeycomb material inside your cat could be all busted up and bouncing around in your cat......happpened to me........

Loochy88

iTrader: (2)

thats what im figuring is going on. did it sound like marbles in a can when you let up on the accel. thats more or less what mine sounds like at idle.

98dropta

iTrader: (10)

yep thats it..................climb under the car and bang on the cat and see if you hear anything....thats how i found out on mine

98Camarod

iTrader: (43)

Put headers on and get an ory and get rid of those cats. You can sell your cats to a local junk man. I got 65 a piece for them

98dropta

iTrader: (10)

i debated that when i switched out my cats.....but i have GMMG and have heard it has too much rasp without cats

Loochy88

iTrader: (2)

well i plan on doing an ory, but no headers. i dont want to fool with headers on this car. i had enough fun with them on my last one. what options are there for ypipes with stock style manifolds on a 99.