Removing 328 cylinder head

The picture in the manual shows the torque wrench angled 90 degrees to the wrench/tool, perhaps this is where the idea of 90 degree further tightening is being confused?

The manual very clearly indicates 10kgm maximum torque. Do not turn the wrench any further, another 90 degrees could cause some very serious problems. You snap off a head stud (or pull it out of the block) and you wont be happy, lol.

 

Page B37 is the 308 section of that book. The 328 section does not start until page B44. The 328 and 308 motors have several differences so specs and procedures are different.

In that book on page B50 and B51 which is the portion applicable to the 328 motor it clearly shows and describes the torquing method and use of the degreewheel. It is different on the 328 due to the hourglass 10mm head studs used in 328 that were designed to be more elastic and stretched to create clamping pressure. I consider the entire affair a mistake. 328 is the only Ferrari motor since the old 3 stud 250 of about 1959, and prior motors that had head gasket trouble. Those head studs were ababdoned for the F40, 348 and all later motors. They went back to the old 11mm studs because they worked. My own 328 motor is apart right now and replacement of the 10mm studs is on the agenda.

If it is decided to reinstall the head the original way Ferrari says to torque it to 45NM and tighten an additional 120 degrees. With the head design it is impossible to swing the wrench that far in a single throw so the degreewheel fixture is used to keep track of the degrees per throw. Again I think it a mistake and would just use 11mm studs and torque it the old fashioned way which worked flawlessly for decades before a young engineer decided to continue a long standing Ferrari tradition to fix that which is not broken.

 

Another case of a poorly written and assembled book on the part of Ferrari. They were mixing 308QV and 328 info which were built differently.


Head studs never rip out of the block, they break at the base of the upper thread.

 

The same can be said for many motors but we are talking about Ferrari's here.

 

I referred to the 328 head studs as hourglass in error. They are a simple dual diameter stud of 14mm at the bottom and 10mm on the exposed half.

I knew what I meant but just wasn't smart enough to type it the first time.

 

Understandable error, The WSM wording has always been slightly ambiguous on this point, however, there is a very clear unambiguous statement of what was intended in the Euro 308 QV Owner's manual #248/82, under Valve timing data page 66:
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It shout be held in place to prevent turning by the magnetic base. It will move through the small arc though, you are correct.

It was a bad procedure with poorly designed parts and tools.

Buy new studs.