LS4 Performance - Those of you with a Hogan catless DP please read

Hey anybody out there with a catless DP notice what can best be described as a tinny ticking or chirping sound at medium to hard acceleration ? im noticing this sound and its driving me nuts... i checked for leaks... there are none... it sounds almost like acoustic resonance of the exhaust pulses in the DP... just wanted to see if anyone else out there is in the same boat... Thanks

The only time I heard any ticking was when it had a leak. Turns out the nut gauld up on the stud, it appeared tight so I figured it was. After ~100 miles or so I had to figure out what the trouble was. Had to replace the nut and stud, that was a pain in the ass.

only time i hear that noise is when the car is cooling off after i shut it off

No noise, just raspy as all get out.

I get the same noise, I just got a used catless Hogan. Hopefully it'll go away.

Just a suggestion. Try wrapping the down pipe with one of the many available heat wraps, like the ones used on headers. Should insulate that sound. It would also keep the heat in the pipe, out of the floorboards and keep exhaust velocity up (hotter air in pipe = increased velocity = good)

I've had this sound with both my current DP and the one on my GTP. I think it is fairly common and I believe it is resonance in the pipe as well as some noise from the flex-pipe which is also considered normal. The ticking noise never bugged me enough because, to me, the performance upgrade makes up for the annoyance.

Just a suggestion. Try wrapping the down pipe with one of the many available heat wraps, like the ones used on headers. Should insulate that sound. It would also keep the heat in the pipe, out of the floorboards and keep exhaust velocity up (hotter air in pipe = increased velocity = good)

I wrapped mine and I seem to be one of the only ones not getting this noise. May be on the something here.

I wrapped mine and I seem to be one of the only ones not getting this noise. May be on the something here.

I get a tick like that on my GT. It has a Hogan DP 3in-2.5 with a highflow cat. I think its a leak and im to lazy to fix it. But alot of peeps on Clubgp forum say it needs to be header wrapped and it will quiet down.....

mine does the same thing, sounds like a leak. had the car in the air multiple times and no leaks! must be common with these. was thinking about wrapping mine but doesnt bother me that much.

The tick may be the rasp. I loved the way mine sounded with the cutout and cat, now that the cat is gone I don't like it so much.

hmm... thanks for all the input... im going to put it on a lift at my friends shop this weekend and wrap the hell out of that pipe... we'll see what happens... i spoke with Kurt from Hogan and he said hes heard of something like that before... he mentioned that over time these DP's will develop a "patina" over the surface and the the patina itself will insulate the sound... but im going to wrap it anyway... that sound drives me INSANE !!

I've actually sent mine back to Hogan and he reports no leaks.I have a catted DP right now, but just bought a catless one to replace it. I should have the catted one for sale soon.

I've actually sent mine back to Hogan and he reports no leaks.I have a catted DP right now, but just bought a catless one to replace it. I should have the catted one for sale soon.


i was just wondering instead of buying the catless one why not cut off the cat and put a piece of pipe in its place?

i was just wondering instead of buying the catless one why not cut off the cat and put a piece of pipe in its place?
Edit:

That could work if you have a catted hogan

i was just wondering instead of buying the catless one why not cut off the cat and put a piece of pipe in its place?

Mine is modular also, just don't have a straight through pipe. I purchased the catless because I was under the impression that the catted Hogan I have is leaking because of the same noise the OP posted.

Edit:

That could work if you have a catted hogan

I've actually sent mine back to Hogan and he reports no leaks.I have a catted DP right now, but just bought a catless one to replace it. I should have the catted one for sale soon.

thats what he said he has now.

ok i was just wondering.

thats what he said he has now.

ok i was just wondering.

that's why I edited it. I put it like that to eliminate any confusion.

Mine does the same thing...I think. I haven't had it on since about June or so, though.

Do you guys realize that the stock downpipe is double walled from the manifold to the cat. That is why it is about 2.25 inches diamater in the inside. GM did not build the stock downpipe for performance at all. You go to a 3" single wall that has a little thinner steel and now you have noise. This is why wrapping it with header wrap quiets the noise down.