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Discussion Starter #1
Is there a possiblity of a cam bending and staying bent if it's been in a head that was twisted?? Cams are pretty strong, what are the chances of it being bent?

Or could it be the head? It was twisted at one time and had it been straightened at a machine shop. Could their workman ship be questionable?
 
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There is a test for this:
machinists can put cams & cranks on V-blocks & with a dial gauge, measure if they are warped too much as they turn them.
also see TSRM page: EM-47

If your head was quite warped, the cams would excessively chew up the cam cap bearings & you would see score marks in the MIDDLE of the cam saddles (which would be the head).
Your oil clearance would also be compromised I would think. Since the cams would be trying to stay straight in a warped head & will beat it up. Aluminum VS. Cast--no contest!
 

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Discussion Starter #4 (Edited)
That's kinda what I figured. Reason I ask is because I had a strange noise start yesterday, sort of like a muffled rattling noise from inside the cam cover and running rough. I removed the cam cover and started it, as soon as it idled down the noise was apparent and sounded like it was coming from the exhaust side.

I checked the camshaft bearing caps to see if they were all tight, turns out there were about 4 that had come loose down to 10 N-m. I torqued them up to 20N-m then checked the valve clearances, all checked out within spec.

If the cam isn’t true or if the head is warped would this cause the bolts to loosen? Is there anything I can do like use lock tight or something to make sure they don't come loose again?

I’m going to take the cam to a machine shop and have the runout checked and see if I can get a straight edge and check the head for flatness.

I guess I should also mention that I did helicoil a few of the inserts and this could be where my problem lies, but they did torque down to spec. Is it possible that they came loose because of a warped head? And by them being loose would this have anything to do with the symptoms I’m getting?
 

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Discussion Starter #5
I found my problem... Exhaust Camshaft is toast!

Installed another one, did valve adjustment and it went very well, dead even across the board! Had to redo a helicoil then another stripped! Drilled and tapped once again... Long day will be firing her up tomorrow.

Hopefully I fixed the problem.
 
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