KF4CTOR

I’ve looked around online, but can’t seem to find a direct answer. There may not be one, but it can’t hurt to ask. Thanks in advance.

The car is a 2009 z51 M6 LS3 with 31,000 miles. The car was stock when purchased, and the current modifications are as follows: 1 5/8 Billy Boat Headers, 2 1/2 Billy Boat X (no cats) with Billy Boat Bullets.

I’ve owned cars with headers before, I know an increase in valvetrain noise is expected but this is rediculous. I’ve triple checked all exhaust clamps/connections from the heads back to ensure there are no leaks after multiple heat cycles, and even added copper RTV to all connections to ensure there is no exhaust leak. I’ve retorqued the header bolts, and they are no longer changing torque after multiple temp cycles. The noise that I hear seems to be dependent on temperature, and increases as engine temps rise. It rises and falls with RPM, but isn’t noticeable at idle from inside the car. The sound seems to only occur under load, as I can’t notice it with the car on jack stands holding steady throttle. The only way I know to describe the sound is mechanical ticking. It wasn’t present before the header/exhaust install, but now all but ruins the driving experience. This evening I added some sea foam fuel treatment thinking that it may quiet a noisy lifter or injector, and I will find out tomorrow on the way to work. I know hundreds of us have put headers on these cars, and I find it hard to believe that this level of noise should be expected to hear inside the interior of the car. Any advice on troubleshooting steps, or insight will be greatly appreciated.

enventr

Check each exhaust bolt carefully. My old muscle car had a ticking noise like a lifter! It was a loose bolt on the headers . I tightened all exhaust bolts . Good luck to you. When you find the solution please post.

doomi

It's hard to know how to scale your sound based on an internet description, but I had very similar concerns after I installed headers. Not incredibly loud, but a noticeable enough new noise to really bother and worry me. And the conditions where the noise occur sound similar.

I immediately started researching for ticking noises on C6's. Rechecked everything a thousand times, removed the headers for all new gaskets, tightened every connection, fogged the exhaust, ext. I was even worried about a lifter collapsing after heatsoak.

That was a couple of years ago and the noise still exists. At this point I'm convinced it's increased valvetrain noise due to the headers.

449er

I know that you checked, but that ticking sound is a sure sign of exhaust leaks

CJ Willys

Is it possible that you damaged a plug wire, and it is arcing? How the engine running?

extrapilot

Not sure how long your install of the headers were, but depending on the material of the gasket (header), it's possible to have a piece blown out or missing from one of the exhaust ports, that would certainty be making the ticking noise. Also, check for arcing SP wire, which was already mentioned.

Don-Vette

Sounds like an exhaust leak.

K-Spaz

Those exhaust manifold gaskets generally are good for many install/reinstalls. I'd be checking the mating surface on the headers to be sure there's not scratches on them causing this to recur.

Also, when I put headers on, I swap out those crappy bolts with ARP stainless studs/nuts. A MUCH nicer setup. Never had to re-torque one.

d-rockRN

On one of my previous corvettes I had OBX headers installed.... sounded great..... over the course of time the headers on the passenger side eventually came into contact with part of the frame..... It gave an awful noise as the car heated up and giving it gas in neutral made it sound worse. I eventually shaved a maybe an 1/8th inch off the frame and it resolved the issue.

SladeX

My first cam/headers 98 LS1, I had some ticking from incorrect pushrod lengths. Even after I got that fixed, I still had an occasional off beat tick (more like crazy loud clacks) from some lifter bleed which would make it sound pretty nasty. Stock lifters. I daily drove it until I spun a rod bearing some 4 years later with the occasional loud tick.after some hard runs or randomness at intersections.

On my LS3 build, I went with some really good after market lifters and now I only have the standard LS sewing machine sound. I am STILL using the same exhaust gaskets from my LS1 build so that gives an indicator on how well these exhaust gaskets hold up.

Surf Island

I had the same concern after headers/exhaust professionally installed. I brought it back for the installer to listen. He said that is perfectly normal. A side-effect of the long-tube design and material, I'm guessing. Anyway, that's what I was told.

ValegoC6

I agree ^^^^

KF4CTOR

Thanks for all of the input and advice, I used the aftermarket gaskets that came with the headers, I’m going to order some OEM gaskets and ARP bolts and give it a shot. This was the first time I’ve posted anything on the forum asking for help, and the community did not disappoint!

K-Spaz

If the gaskets that came with them were thick and soft, yes I would say they really need to go. The OEM gaskets are several layers of thin Steel. There's nothing to compress so they don't need retorqued to stay tight.

89talon

I have pronounced valvetrain noise after longtubes, xpipe and cat delete with NPP exhaust. It is perfectly normal. I just asked my coworker who has same setup and he stated the same thing. It alarmed me as well when I first installed the exhaust. Enjoy the new power!

LeMansBlueLS2

I too have pronounced valve train noise. I just had a H/C/I package installed at RPM in Delaware (their Stage 3 package) and was concerned of an exhaust leak with the American Racing 2” headers and catless x-pipe but I came to learn that it is just the characteristic of the whole package together. I’d check the gaskets if you used what came with the kit. I’ve heard that they are junk in some cases. I’d throw in some OEM gaskets and if it still persists, you know its normal.

89talon

Also if you just had the exhaust installed after a few heat cycles some of the header bolts may need to be tightened. A 13mm socket will handle the job if you used stock header bolts.

hmmmm16417

THIS!




I had the same issue and instantly regretted changing the exhaust thinking it was a bigger issue than what it was. Definitely a leak. I had to end up replacing all clamps with lap joint clamps to seal it up AND good header gaskets.




if you're unsure where it is coming from you can use a piece of rubber hose about 2-3 ft long like a stethoscope near all joints and manifold and you'll find it fairly quickly.




Here are the gaskets and clamps I used. these are the best clamps. don't buy cheap ones, these ones work better than ANY other knock off. Most of my TICKING noise was from the joints between the Xpipe and the rest of the exhaust. these clamps (second pic) conformed to the shape AND have sealant on them.... they can be tightened very hard without breaking and/or stripping. Once I replaced all 4 connections with these , and put these thicker gaskets on ..... ticking gone

cmonkey713

Nine out of ten times that's it. Pull the side that is ticking and replace the gasket with the best gasket money can buy.