jmargo

iTrader: (10)

Checking the torque on the rocker bolts since its been a few k miles since I did the trunnion upgrade and decided to actually use a torque wrench to tighten down the valve covers. On a whim I checked the intake manifold also. Set the wrench to 89inlbs (yes inch pounds) and the bolt turned. I decided to take it down to 44inlbs and those turned too. This is a untouched 30k mile LS6. I went through and torqued them down in sequence with slight settling. Did I do something wrong ? Is this sequence just to set the rubber gaskets ? Are these manifolds known to loosen up over time ? I would guess they were at about 35-40inlbs before I started.

99Bluz28

iTrader: (35)

When you last torqued them down how many times did you go over them?
I usually have to go back over them in sequence 3-4 times until the manifold's fully seated and they all stay torqued to spec.

jmargo

iTrader: (10)

Last person to touch the manifold was in 2004 at the factory.

Burken01

iTrader: (88)

Could be the gaskets flattened a little over time... Creating a little gap...

chrisfrost

iTrader: (8)

Yes gaskets for sure and that many hot/cold cycles takes its toll on plastic/nylon and metal as well especially aluminum,,,,,,,,,,,not surprising at all