intake torque spec confusion

[turbox4]

I noticed this board and other boards specify 32 ft.lbs. torque for the intake manifold to head. In the Guide to Buick Performance engines in the General Torque specs on page 162 it states 45 ft.lbs. Then in the Stage 1 block section of the same book it states 25-30 ft.lbs.
The factory service manual in section 6j-24 states 44 ft.lbs and 60 N-m.
Both Haynes and my big and little Chilton shop manuals all state 45 ft.lbs. and 60 N-m.
Am I missing the fine print or did I just miss the memo?
This comes up as I grabbed the shop manual and retorqued mine to 44 ft.lbs. Nothing broke.

 

[3point8]

intake torque specs

Well George, I had a similar problem. a day or two after I torqued my hot air intake to 45 lbs I was reading something else and ran across a different spec. for the same bolts. I figured it was too late to go back. That was two years ago and its still running OK so I am no longer sweating bricks.
Peter

 

[750H.P.V6]

George,

I know there is some confusion here. I had always torqued my intake manifold bolts to 40 ft lbs when using stock iron heads. This torque spec will not work for aluminum heads as you will more than likely pull the threads out of the head. With this said 25 ft lbs is more than enough so now we torque all our intake manifolds to the lower value. I hope this makes sense.

Neal

 

[turbox4]

Thanks guys. I suspected it might have something to do with the iron vs. aluminum heads and maybe the factory issued a manual update to cover the aluminum heads later on. I will consider myself lucky this time and leave well enough alone but will for sure use the lower value in the future. I really appreciate the responses and will sleep better tonight.

 

[Nick Micale]

Originally posted by 750H.P.V6
George,

I know there is some confusion here. I had always torqued my intake manifold bolts to 40 ft lbs when using stock iron heads. This torque spec will not work for aluminum heads as you will more than likely pull the threads out of the head. With this said 25 ft lbs is more than enough so now we torque all our intake manifolds to the lower value.......Neal

The higher torque can also break/crack the intake on alum heads!