Cylinder head torque sequence

[Stevehose]

I see different torque sequences from different sources. The coupe manual:

And the commonly found sequence found online and in the head gasket instructions:

What are the pros and cons of each? My last head gasket install I did the manual's version not the gasket instructions.

 

[rsporsche]

the gasket approach is the way i have always seen / heard it described - always starting in the middle but working outside on opposite corners. what seems to make sense about the BMW approach is that you get both sides of the head (at one location) together before moving back and forth to the other side.

 

[sfdon]

Test each bolt to bottom of bore and always oil the washer

 

[lloyd]

Frankly, I would be inclined to follow the gasket manufacturer's advice as it (presumably or more likely) incorporates upgraded thinking and improved gasket technology. Indeed, even BMW (circa 1985) revised its recommendations, incorporating an "angle torquing" procedure (see below). Since most tightening is done in stages, this has a tendency to equalize different torquing loads.

To the best of my knowledge, I have followed all recommended procedures (including a few that aren't posted) and can't recall having any short term failures. Think about it, you want to evenly spread the torque load of each fastener and even the factory allows for some leeway regarding most recommended torque specs. I can think of many permutations that probably accomplish this. Having the cleanest bolts/studs/threads and the appropriately clean and smooth mating surfaces is generall the key to success. An accurate and reliable torque wrench is probably not a bad idea either.


http://www.e9coupe.com/forum/showpost.php?p=60555&postcount=6

 

[HB Chris]

I used the later approach, diagonally.

 

[Stevehose]

I forgot to mention my last gasket came from BMW with no instructions so I went with the manual. I will have a comparison thread in the near future. The Elring instructions had the diagonal sequence.

 

[m5bb]

I used the later approach, diagonally.

I do the same on the M30 motor and also the same for the S38.

Gary