Rvettej

I was just wondering if anyone could help. After installing kooks headers, x-pipe and corsa extreme exhaust on my 2007 Vette with the LS2, it sounds like it has a header leak mainly on the driver side but it doesn't I replaced the gaskets with Percy's "dead soft" and checked with soapy water (while the engine was cool). I'm using MSD wires and NGK TR6 plugs not knowing if the colder plug is giving me the problem since I'm not supercharged or using NOS. Any ideas out there?

c4boom

iTrader: (1)

check o make sure all the primary tubes are not leaking some times they miss with the weld. Also check the collectors and the spark plugs to make sure they are tight and that seats on the plugs are good with no gouges or any thing.

SSexiness

iTrader: (2)

Does the noise increase or more noticeable as rpms increase? Are you able to see any carbon build up (around collectors, heads, etc..). I had a similiar noise after installing mine, the tubing for most after market headers is thinner than the factory equipment which makes the exhaust/valve train noise more noticeable. The noise was less noticeable after a few weeks since some carbon was building in the tubes but i can still hear it.

Tally TransAm

iTrader: (17)

valvetrain noise is gonna be significantly louder after headers are installed so make sure thats not what you are hearing

wht01ws6ta

iTrader: (45)

Yeah the header walls are a lot thinner so you can hear lots more valvetrain noise compared to the stock manifolds. You changed the gasket, checked with soapy water somehow and didn't see anything, if you don't see any black carbon anywhere from a leak you just might not have one.

Rvettej

Thanks everyone I had more replys than expected. Trying to respond to all, I checked the spark plugs they seem fine I will have to check the primary tubes, also no carbon anywhere I can see. As for RPM and noise I notice it the most @ about idle-1200 also seems to be sluggish around these rpms with like a pinging sound, but before the header and exhaust change I didn't have any of these problems. As for valvetrain noise thats what I was afraid of, I didn't want to hear that. Does any one think its a tuning issue?

c4boom

iTrader: (1)

it could be false knock caused by the headers rubbing. the knock being the noise and the pull in timing being the bog. also a leak can skew the o2 causing the sluggish ness

bayer-z28

iTrader: (14)

Yeah.. Headers are noisy... even more so if it's your first set.. Thicker wall tubing helps...

But here are some guide lines:

Pulsing noise is a primary leak
Constant 'whistling' is a collector leak..

Rvettej

c4boom, can you fill me in on the "pull in timing" I'm not sure what your talking about. Also for Bayer-z28 what would be a good set of thick wall headers? I have stainless steel "Kooks" currently.

bayer-z28

iTrader: (14)

^ Kooks are some of the best.. You can't go wrong there.. They are naturally noisy tho.. It takes some getting used to.. Just re check the header bolts every 1000 miles and if you don't see any black suit around the collector, you're good.. But I'd advise getting it tuned shortly after the install.. Something about the increased flow kills gas mileage w/o a tune.

I had the exact same question after my first LT install. The noise is normal.. .as long as it's not a knocking or pinging noise. -More than what would be normal.

Rvettej

Well currently I'm trying to retune using EFIlive and I've been getting some good and bad outcomes just trying to meet in the middle untill I can get a wideband O2 and gauge. Plus it doesn't help to be a newbie at tuning a car either. As for the nosie what exactly is expected? it sounds similar to pinging but I don't believe it is. using a scope I'm getting most of the noise off of primary tube on cyl. #7, but not all of the noise its very general.

bayer-z28

iTrader: (14)

Maybe some newer Vette Guys can chime in on this..

It sounds like a pinging, but it's just more of the sound emitted when the the exhaust valve opens and lets all of the combustion sound out along w/ the gases. Remember, the stock manifolds are a LOT thicker than headers, so they hold a lot of noise in.

00pooterSS

iTrader: (40)

Its not increased "valvetrain" noise, but it sounds very similar, as stated the thinner the tubing the worse it is, you aren't going to get a better header than what you have, I would venture to say you are just hearing the headers.

**** go listen to an old hot rod with 18 guage painted headers that sounds bad, im sure yours are 16 gauge and being stainless probably helps a bit too.


So hard to try to help without hearing it, a sound clip might help if you can get a clear vid.


One way I find exh leaks is with my stethescope and pull off the metal tip and just have the hose end open or use just a piece of rubber hose, and run it along all welds, the flange, the collectors, when the leak blows in the hose in your ear its real easy to tell.

dutinsss

iTrader: (2)

make sure all of your plug wires are on securely. i had a ticking sound that sounded just like an exhaust leak and i couldn't find it anywhere. i messed with the wires and the far back one on the drivers side wasn't snapped all the way on. as soon as i snapped it on, it went away.

Rvettej

Thanks for the help guys, I was wrong with the stated RPM range above, I double checked and under low throttle it makes this noise from idle-to roughly 3000 RPM maybe higher but can hear it from the exhaust and is sluggish at lower rpms. I've checked everything mentioned so far, also used the stethescope (except for taking off metal tip, I will try that). I've been all under the car (even while running) no leak to be found. But seems to be the loudest around the collector. Could it need tuning? Or possible bad combination of exhaust? LTs, 3" X-pipe and Corsa Xtreme (back pressure?). I know it "Pops" back when you throttle quickly and let off (not to mention I HATE that noise). So I don't know what to do, I just about ready to pull it all back off and go stock.

Rvettej

Well thanks for all the help from everyone, exspecially,00pooterSS for giving me the stethescope without the metal tip idea. With that a small header leak was found around a primary tube and flange, and wasn't found because it didn't show any signs of carbon for it to be leaking. Any way now just need to have them welded somewhere this suxs really bad for new headers to be leaking.

Intercooler2

iTrader: (24)

Just header noise. I get it too and it is a little annoying but I know I don't have any leaks. Just gas pops in the tubes

00pooterSS

iTrader: (40)

Hellz yeah put some bubble yum on that f'er and be done with it lol.


Sucks even worse the amount of money spent and still have a set back like that. Good luck with it, and hope you dont have any other expense incurred, if you do I would be looking for a labor claim.