[SJFGTO]

If it is a tick associated with a leak you should be able to pin point the location and the leak my be enough to set of a CEL. If the tick occurs immediately when the vehicle is turned off it is the metal cooling down. Otherwise, unless it is a bad lifter, which you should be able to somewhat isolate, it is likely just the much thinner metal of an exhaust header as opposed to an exhaust manifold reflecting normal injection or valve train noise. Common and not a reason to avoid LTs IMO.

[BMWM.D.]

Originally Posted by GT-ER

Yes, correct. While idling.





You may be right. I see you point.



Cel phone doesn't seem to pick up the sound like I can in person. It's just a very high pitch ticking that comes from the bottom of the car near the front wheels while the car is idling. Sounds like an exhaust leak, but isn't.

Does anyone know if wrapping them fixes it?

Maybe yours is louder than mine with Kooks 1 7/8”, but I was actually pleasantly surprised with how quiet and civilized the LT4 is with long tubes. Maybe it’s because I had expectations based on headers that I’ve had on at least 5 other SBC and LS builds. Those LS3s (especially my dry sump version) had some pretty loud valvetrains that were made a bunch worse with headers.

It’s hard to say if what you’re hearing is worse due to something with the design of the OBX headers. I hear some very subtle metallic noise from underneath that is very rapid in frequency. Maybe that’s why it doesn’t bother me. It’s not like a lifter tick that’s less frequent and more noticeable. My headers just sound like normal combustion/mechanical noise that’s been turned up a notch or two.

And sorry, I’m not sure about the wrap thing. I’ve never done that.

[Jimabe]

Mine ticks just a bit too. Have -cats and 2" Kooks. NO where near the valvetrain noise from my same-modded LS1, so not really bothering me...
Certainly wouldn't/shouldn't even be close to a show-stopper from doing the mods...

Things to consider:
1. bye-bye warranty
2. Loud as F
3. Even harder not to drive like idiot and get car impounded
.
.
.
58. Global warming
59. Oprah running for president
60. Header ticking noise

My 2c

[Gunkk]

Originally Posted by GT-ER

Does anyone know if wrapping them fixes it?

Did you do a hose test? (hold a vacuum cleaner or whatever hose to your ear and probe around with the other end). You can also try a screwdriver test with a longer stick or rod (hold one end to your ear and the other end on the header) to see which tube is vibrating.

If you've already done the hose/screwdriver tests to verify it's not localized to any one area like the HP fuel pump inlet line or one of the header connections (i.e. a leak), and assuming that it really is indeed a resonance in the header tube metal, then yes wrapping it should help dampen any resonance.

[SecondZ28]

Originally Posted by BMWM.D.

You likely weren’t hearing it before because the cast manifolds mask a lot of the noise. I’d say both injection and valvetrain noise is amplified by the thin walled headers.

This exactly.

[GT-ER]

Originally Posted by Gunkk

Did you do a hose test? (hold a vacuum cleaner or whatever hose to your ear and probe around with the other end). You can also try a screwdriver test with a longer stick or rod (hold one end to your ear and the other end on the header) to see which tube is vibrating.

If you've already done the hose/screwdriver tests to verify it's not localized to any one area like the HP fuel pump inlet line or one of the header connections (i.e. a leak), and assuming that it really is indeed a resonance in the header tube metal, then yes wrapping it should help dampen any resonance.

I did, at home I put a vacuum hose in my ear and went along the flanges and all sorts of areas and couldn't pick anything up. Went to an exhaust shop and put it on a lift and they determined the same thing. It's a resonance issue.

[DangerZL1]

I wonder if ceramic coating the headers would help?

[GT-ER]

So, I pulled the headers and one of them was leaking at the collector. I DID have a leak after all. Looks like I'll be swapping out to another set of headers soon. What gaskets should I use? I used oem ones but don't know if there are better ones.

[SJFGTO]

OEM gaskets are fine. I would consider coating your headers. More expensive, but better looking and you avoid damaging the headers. Wrap can hold dirt and moisture, which over time can degrade the headers. Not a certainty, but it does happen.