GMCtrk

iTrader: (27)

it's got pac 1218's and hardened 7.375's. But I had this noise before the head and valvetrain swap. It all started with the headers but I can't remember if it started right when i put the headers on. I would cap up my cutout so i could locate the noise easier, but i left it at the GTG about 250 miles away. It's supposedly being mailed back to me.

charcold-bowtie

iTrader: (10)

Ive sworn to everything and everyone that since I put shorty headers on Ive had a leak. After talking to other people i think the cast manifolds just soak up that much noise. But thats my guess of things....

viciousknid

iTrader: (8)

Mine kinda tinks when I put it in gear or go from no load to load.
I've wondered if the Flange could be twisting enough to make noises?

And yea. Stock does absorb a lot of noise because they are so thick

BlackGMC

iTrader: (31)

it is your valves slapping shut... The bigger the springs the louder the valves shutting is... Also with headers the noise is loader cause the cast manifold soak up alot of engine noise....

KevinF56

iTrader: (9)

yep. my pacesetters on my old truck had that header tick. you'll get used to it.

00ChevyScott

iTrader: (10)

I'm still not used to mine

KySilverado

iTrader: (7)

Mines even louder when I cold start it. Let it sit and idle for a few minutes and you can hear it progressively quieten down.

GMCtrk

iTrader: (27)

I haven't found a cold start/running hot to make any difference in noise level.

Mangled03gmc

iTrader: (95)

Sounds ok to me, the more spring you have the louder it will be...

nonecktribe

its just your valvetrain your hearing...i thought the same thing that maybe something was wrong but its just that when you change your airbox/headers/valvetrain around you eliminate alot of the sound dampening that manufactures do for the "old people" so they can have a comfortable ride...hence why there is so much more power in them when you modify....it will take time to get used to but its normal...