Timesert and TTY Victor Reinz headbolt question

[ahlem]

2001 3.0
I timeserted the block and thought it was a successful effort.
I torqued down the "lightly oiled" headbolts to 30 foot pounds per the Bentley manual. So far so good. Then the first 90 went 13/14 OK with one bolt on the passenger side between 5 and 6 "yielded" easily before the first 90.
Now what? I figured I'd have to do something to remedy this so I did the second 90.
Creaking and popping on about half the bolts and I stopped short of 90 on those. The other half hit 90 degrees and a couple yielded short of 90.
When I say "yielded", I mean that they seem to have stopped requiring the same torque as before.
Do I need to tear this back apart to see what happened? Is this typical of Victor Reinz headbolts? Did I screw up the Timesert process?
The exhaust manifolds were a PITA by the way and I don't relish the thought of having to redo this but even worse would be to put it the rest of the way back together and have a headgasket failure..

[Effduration]

Tightening the torque-to-yield head bolts on an M54 is a stress-inducing experience, particularly if this is your first time. All the bolts should "yield", but it is unusual that one yielded in the first 90...

Its normal to have popping, squeaking, etc. in the final 90 degrees..

If the time-sert failed, I think it would be spinning pretty freely.

If I were in your shoes, I think I would get another set of head bolts (cheap enough) and do it again. I would not use Victor Reinz but use Elring or made-in-germany Beck/Arnley 016-1048, which is what I use. I use a beam-style (cheaper) torque wrench for the 1st 30ft-lbs and then a breaker bar and a paper dial gauge for the two 90's.. If your torque wrench is inaccurate and the first step is actually 40 ft-lbs that could lead to what you experienced.

[ahlem]

Thanks for the reply.
This is my first M54 but not my first headgasket or engine rebuild.
I've used TTY bolts on the last M20 projects where they replaced the old style.
My plan was to get a different set of head bolts and re-do them one at a time and maybe be a bit more generous on the lube in the non-threaded parts of the bolts. I have several torque wrenches of the lower cost variety so I may set them all to the same setting and see if there is much variation.
I can also try calibrating them to see what they actually read.
Does the re-do one at a time make sense since the headgasket has been compressed?

[Effduration]

Not wild about doing them one at a time. I would remove in the proper removal sequence (reverse the install sequence in order) and re-install in the proper sequence, with a 30 ft-lbs and then a 90 and another 90.

I am not an expert, but I think the proper tightening sequence is as important for the cylinder head (alum, 6 cyl, prone to warping) as it is getting a proper head gasket seal.