: proper torque-to-yield on 99 sts



knon2000
07-17-11, 09:52 PM
I am at the point of tightening my head-bolts, and the FSM says tighten to 30 lbs/ft on first pass, second pass -70 degrees, third pass also 70, with final pass at 60 degrees for a total of 200 degrees.
This is not what I have seen listed in several threads? Which method should I use?
I also seem to remember something being mentioned about the timing method listed in the FSM not being correct. I can't for the life of me find that thread back, is
there anything to that? The shop manual seems pretty dang detailed to be incorrect, but, hey, we are all human.
Thanks

JoeTahoe
07-17-11, 10:21 PM
are you useing studs and nuts or stock head bolts??

knon2000
07-17-11, 10:26 PM
felpro "stock" head bolts, sorry, didn't think to mention what I was using.

98eldo32v
07-18-11, 01:08 AM
You're using stock head bolts?:helpless: WOW?!

89falcon
07-18-11, 01:25 AM
I am at the point of tightening my head-bolts, and the FSM says tighten to 30 lbs/ft on first pass, second pass -70 degrees, third pass also 70, with final pass at 60 degrees for a total of 200 degrees.
This is not what I have seen listed in several threads? Which method should I use?
I also seem to remember something being mentioned about the timing method listed in the FSM not being correct. I can't for the life of me find that thread back, is
there anything to that? The shop manual seems pretty dang detailed to be incorrect, but, hey, we are all human.
Thanks

IIRC, all of the talk about incorrect timing methods in the manual pertain to the 3.6 liter V6....the engine actually has different colored links in the chain instead of timing "marks"......the only strange thing about the N* timing is that if you rotate the crank 720 degrees, the crank mark will NOT line up with the mark on the intermediate sprocket.

Bad call on the Headbolts IMO. If you're sticking with bolts, you should only do so with "Norm's" inserts....and if you use the bolts, you should be using the factory ones......I've heard of problems with aftermarket bolts......

I think there was a TSB that went out about the procedure......and the new procedure puts even more stress on the bolts in an attempt to get a little more clamping force.....but with more failures during installation....

knon2000
07-18-11, 06:17 AM
I made my own inserts. Much better than Norm inserts, at least in my opinion. I don't know that factory bolts would be better than felpro, and considering Jake's well known quality control issues, I really don't feel the least bit worried about using a company with a felpro's quality record.

Submariner409
07-18-11, 08:35 AM
Absolutely nothing wrong with either GM stock or any of several name brand aftermarket head bolts. If it's not gong to Daytona or Talleadega there's no need to go with something like top-drawer ARP.

The timing chain setup is in a diagram in one of my two red Seville albums up in Community, Albums.

89falcon
07-18-11, 10:43 AM
I made my own inserts. Much better than Norm inserts, at least in my opinion. I don't know that factory bolts would be better than felpro, and considering Jake's well known quality control issues, I really don't feel the least bit worried about using a company with a felpro's quality record.

Better than Norm's? in what way? are they longer? bigger?

knon2000
07-18-11, 07:27 PM
They are longer. I also included the locating dowel on the inserts.
Made it really easy to remove by just drilling them out using the inserted fixture
that I built.
Really helps that I am a machinist with access to the materials that are needed.

JoeTahoe
07-19-11, 04:16 PM
if no one answers you on the torque spec. I will when I get it from my FSM when I get home from work

knon2000
07-19-11, 09:10 PM
No problem on the torque spec. I was just questioning it since I thought I remember reading a thread where someone was recommending lower starting torque and yeild angles.
I already have the FSM, thanks anyway.
Kevin

stoveguyy
07-20-11, 10:52 AM
longer is nice but how do you know how much material is at bottom of threaded hole? do you have a block diagram from GM? seen a few comments on cracked blocks due to using oversize thread inserts. sure there is a limit on thread diameter and thread depth. so you might say your inserts are better since they are a "little" longer.

97EldoCoupe
07-20-11, 11:19 PM
and considering Jake's well known quality control issues.

I will take note of this comment for future reference.

tateos
07-20-11, 11:37 PM
I used Norm's - before Jake's time - and FelPro bolts - snapped 1 bolt on install. Removed all 10 on that (R) bank, removed the broken remains, Rock Auto sent me a complete new set no charge. All of Norm's inserts were still fine, including the one in the problem hole. No issues the second time around or with the L bank - I think it was a fluke.

I used the 30/70/70/60 procedure.

P.S.: For you guys that know/remember me, Numb Nuts is still driving the car...with no more DUI incidents lately!