Good Evening Fellow Engine Gurus! Looking for a little guideance before I get too carried away!
Background/Build:
2013 Camaro SS - 7.0 427 - Wet Sump setup
AHP- Heads Ported Moldstar90 Guides - Stock LS7 Intake Valves, SS Exhaust valves - Hardened Push rods - with LS7 Rockers with Trunion upgrades.
Darton Sleeved 4.125 Block Aluminum 5.3 block
Full rotating assembly I bought off someone out of a 2008 C6-z06 engine - So Stock z06 Internals down to the bearings - mains, rods, and cam all what you would find in c6 z06 06-2013 LS7 motor
Had Rotating assymbley all checked and internally balanced by local machine shop before assembly.
PG - Custom Grind Cam
FAST 102
NW -102
CAI -
Long tubes full GM ZL1 quad tip exahust minus cats
LS7 42lb injectors

Build might have 3K miles on it give or take total in year.

Now the bad and my reason for the post Drove the car to dyno today to get some rwhp numbers car drove like a monster there and back no issues what so ever running wise or tune log wise that I could see no CEL nothing car seemed to run STRONG - But something on the passanger side head/header area is making a really loud noise that aint right and this just started like all the sudden cause I drove the car once last week heard NOTHING like this setup the dyno day and get there and dont dyno in fear of it blowing up on the dyno LOL.

So attached is a link to a short video clip I took of idling in my garage which you can hear the sound clearly and also attaching a log of the drive home from HP Tuners if anyone cars to take a peak and see if a missed something?! No I have not fully checked the exhaust or any exhaust bolts so small chance its a loose at the head somewhere or down by the collector, but if its not exhaust where is my next check in diagnosing this mystery noise? This car is KILLING me! But I love it lol Sounds horrible IMO but if you drove it you would smile! lol its weird. im stumped.

Copy and Paste this link in your browser URL: https://drive.google.com/file/d/1jwX...ew?usp=sharing

Thanks for any and all suggestions taking the time to read all my junk here.

 

sounds horrible I wouldn't drive it any more. Either a HUGE exhaust leak or lifter issue. I'm guessing the later because I am hearing a major misfire.

exhaust trick: spray soapy water all over the exhaust/headers. push air through with a shop vac on the exhaust tips. bubbles will show your leaks.

 

i agree sounds rough! Just developed like out of no where too… but i agree could be a lifter! Pretty shitty if it is only 3k miles on those lifters smh maybe…

as for misfires had zero while driving all the way home logging the data live for each cylinder with hp tuners.

thanks for the exhaust leak trick didnt know this one!

 

Ooooof. Doesn’t sound like an exhaust leak to me, but I’ve been wrong plenty of times. I’d pull that valve cover for starters and have a look. Sounds valvetrain related to me.

 

Also noted an will do especially if im pulling a head for a lifter after 3k miles lol

 

BTW these are the exact lifters I used with 3k miles or less on them if 1 did fail…should have went johnson 2110s
Chevrolet Performance – Racing Hydraulic Roller Lifters (88958689)

 

For sure pull the valve cover, inspect the rockers, check valve springs... I think you may see something right away given the sound.

 

Agree, possibly a broken valve spring?? I wouldn't even THINK about cranking the engine over until I knew for sure.....

 

Pull the valvecover... probably a loose rocker arm... hopefully.

 

That sounds valvetrain related; loose/broken rocker arm or broken valve spring. Sorry you're going through this, many of us have been there, it'll all work out.

 

The sound file is no longer available. What did you find out?

 

Another abandoned thread... Really annoying when searching and you find your issue (or similar) and end up with an abandoned/unresolved thread.

 

Amen, bro.....

 

@c4love Hey, guy. Did you ever resolve this? Inquiring minds would like to know!!!

 

I’d question which brand of rocker trunnions he installed too .