Nuts... Ferrari specified torque values

Why are you interested in changing what is already there?

Also, McMaster:
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When engineers and designers specify torque, it's often based on a desired clamp load. That is one reason you can't just use a standard torque chart based on a fastener size. Ferrari is known for using fine threads for many fasteners.

Will it be OK to make a change? Perhaps. I would personally keep the fasteners as designed and torque to the proper specifications.

 

Which "workshop manual"? Sometimes they make typos or get items confused. Both the 308GT4 WSM and the Mondial8/QV WSM show a torque value for those that is much lower, and wouldn't alarm you. The 308QV/328 WSM shows a somewhat higher value (7 daNm/51 ft-lb) even though they all use the same bolts/nuts (so I'd be a little suspicious of that), but for an 1980~81, I'd give more weight to the earlier WSMs -- JMO.

 

If I'm understanding you correctly, you are referring to the bolts that secure the ball joints to the upper and lower control arms. One is a 10mm, the other an 8mm. As with virtually all suspension hardware on these cars, the nuts are Class 10. Regardless, they are all nylocks.

And, depending on which WSM you are using, the torque spec for the 8mm fasteners is greatly overstated.

YMMV

 

Nyloc's can be reused a few times, but I would not reuse them on critical connections.

 

Hi Andy,
Yes, Ferrari did supply Nylocks as original equipment in the locations you specify. And no, we do not reuse Nylocks, wave washers or lock washers. To imply the possible reuse of a locking fastener infers no understand of either the fastener design limitations or the concept of personal/professional liability. All of the components in the suspension are critical to your safety and those around you. All of the odd an/or Ferrari-specific hardware is readily available and inexpensive.

Also, from your photo, the large bolt for the sway bar link points rearward, with the nut on the back side of the arm.

Nice work...we did a 328 not too many years ago with a similar setup.

 

Hi Andy, as I said above, I would not reuse a Nyloc in a critical application which yours certainly is. But, as an example, the 355 undertrays are held on with Nyloc's and there is no issue reusing them for that purpose or other non-critical applications.

Now the reuse does have limits (number of times).

 

You're welcome. The coil over project I did was on a very nice 328 GTB.

I've been at this 34 years and have done hundreds of similar projects. Between misinformation and the often cryptic WSM, things that are simple (or should be simple) can often get far more complicated than they need to be.

Regardless, this should be a very rewarding upgrade.

 

This is just a side note to all this but in the aviation industry I work in... all "single use" self locking nuts are tested during qualifying after 10 cycles of running on and off the bolt and they have to meet the self locking torque after those 10 cycles. So while I agree that you should not reuse them... they are most likely good for more than one use. The self locking torque on a bolt that size (10mm) is in about the 10 inlbs range at breakaway in the unfasten direction. (breakaway measured from a full stop on a nut on loose bolt i.e. not fully clamped up and installed, just on bare threads) So there is a way to test them if you are in a bind and cant find a replacement. If you want to try to save them never use a impact gun, only hand remove them. Using a gun heats them up and trashes the insert. Your first choice should always be replacement.

 

Thanks for sharing this information, Hal. I find it interesting on how the aviation industry views this problem, where safety takes on a whole new meaning. The challenge that I run into, specifically for fasteners in critical locations, is just how many times have they been removed. Oftentimes, the nylon is badly deteriorated and the nuts can simply be spun off with my fingertips.

 

My final solutions...
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For non critical use: If you cant turn the nylock by finger then it should work ok. Most fasteners are over tightened by some people, which is worse. We had a guy that we classified : "TIGHT" and "LEO TIGHT". You couldn't get it loose after LEO TIGHT. But Leo started out in a steel mill, and everything was huge!

 

Nice...

 

Great information, Hal. While I certainly like to do things the proper way, common sense goes a long way. No point replacing perfectly good hardware for non-critical applications.

On the motor I'm rebuilding, I'm replacing most hardware as it's very corroded. But, for something like a cam cap nut that is covered in oil it's entire life, I see no need to replace those as it would make little sense other than flushing $$$ in the toilet