2009 Aveo 1.6 head bolt torque specs

[keenyoung]

Not yet. I just got the cylinder head back from the machine shop. Still waiting for the timing belt kit.

I have decided to go with the 25 NM +90+90+90+45 spec.

My local Chevy dealer service manager looked at his service manual, and it was exactly the same as the digital one I have. Two different specs for the head torque. He insisted that his mechanics would follow the the 90+90+90 one, because that was the one in the body of the section to replace the cylinder head.

I also had another qualified mechanic tel me that the 90+90+90+45 is for the engines witn variable cam phasing, and the 90+90+45 sped is for the engines without the phasing.

I'm still worried, but I'm gonna go with the three 90's one and hope for the best.

I will update the thread when I have a running engine.

Thanks for the help,
Keen

[petrified.rabbit]

As long as you do it in the right order, tighten them evenly, and don't snap a head bolt, you will be fine. The worst part of over tightening is if you need to remove the head down the road, you might snap the bolt. Typically, one extra 90* turn won't hurt in assembly. It's not like your putting them on with an impact..