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Discussion Starter · #1 ·
Almost done with my headers. Just doing the final nut & bolt check and tidy up. Is there a TQ spec for the header bolts? If so, what is it? I don't have a FSM or I would just use the stock exhaust manifold bolt TQ.
 

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well like jack said. nice and tight would do but do a star pattern, like wheels. Go over each bolt a few times... what you could do is start at a low torque go through a few times go higher 5 ft lbs again and last 5 lbs higher. its not in any manual but if it works for the hubs of my airplanes, trust me it will stay nice and snug. I bet this sounds rather odd. enjoy!
 

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Discussion Starter · #4 ·
well like jack said. nice and tight would do but do a star pattern, like wheels. Go over each bolt a few times... what you could do is start at a low torque go through a few times go higher 5 ft lbs again and last 5 lbs higher. its not in any manual but if it works for the hubs of my airplanes, trust me it will stay nice and snug. I bet this sounds rather odd. enjoy!
I thought headers get torqued from the inside out?
 

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I thought headers get torqued from the inside out?
I think thats what he meant. But to start for example if the TQ spec is 40 ft lbs to start at like 25 do the back and forth pattern starting from the middle and go to the edges of the head then go back and tighten to 35 lbs and then go bak and do the final tighten to spec.

Please note that the TQ spes I listed are ONLY EXAMPLES I do not know what the TQ spec is my post is meant only to give example of torquing in steps.
 

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well....lets see headers get super hot then cool off. so they contact and a-lot! there not really huge bolts to begin with so i dont think over 50 ft lbs should be your last torque. if you find out let us know! good info to have
 

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To install:
Clean and inspect the exhaust manifold.
Install NEW exhaust manifold gasket and NEW sealing ring to the exhaust manifold.
Install the exhaust manifold assembly to engine.
Install the NEW exhaust manifold to cylinder head retaining bolts.
Tighten the exhaust manifold to cylinder head retaining bolts working from the centre to the outside to 15 ft. lbs. (20 Nm).
NOTE
Make sure the sealing ring is seated correctly.
Lift the left catalytic converter up and forward to connect to the exhaust manifold.
Clean the threads of the exhaust manifold to catalytic converter retaining studs with a suitable cleaning solvent.
Install the NEW left catalytic converter to exhaust manifold retaining nuts and tighten to 33 ft. lbs. (45 Nm).
Install the engine coolant temperature sensor.
Position the exhaust manifold heat shield to the exhaust manifold.
Install the exhaust manifold heat shield to exhaust manifold retaining bolts and tighten to 89 inch lbs. (10 Nm).
Install the left side spark plugs to the cylinder head.
Install the left side spark plug leads.
Install the air cleaner assembly.
Install the engine cover.
Connect the battery negative cable. Refer to Battery Negative Cable Disconnection & Connection in Engine Electrical.
 

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Discussion Starter · #9 ·
I ended up torquing mine to 25ftlbs.

Here is another question, for those that have installed the matching Kooks catted xpipe, were you able to reinstall the brace under the exhaust?
 

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BVM, yes, you can install the brace. You may have to put a jack under the exhaust in that spot and lift the pipes before you tighten everything. Mine would still touch and rattle sometimes, so I wrapped the pipes with exhaust heat tape. It still touches the brace, but doesn't make any noise.
 

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Discussion Starter · #11 ·
Thanks nda, I'll have to take it to the hobby shop on base and do it on a lift.
 

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Thanks nda, I'll have to take it to the hobby shop on base and do it on a lift.
Headers should have come with 1/4"-1/2" spacers that you should use to space down the tunnel brace.
 

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Discussion Starter · #13 ·
Only spacer in my box was for the dipstick. WTH?
 
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