Camshaft cap fasteners | FerrariChat

Camshaft cap fasteners

Discussion in '308/328' started by miked, Jul 29, 2024.

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  1. miked

    miked Formula Junior

    Feb 7, 2001
    898
    Cincinnati, Ohio
    I am slowly (glacial speed) doing an engine out refresh on my GT4 engine, currently remounting the cams after replacing the valve stem seals. The fasteners were a mismatched mixture of nuts and washers so I am going to replace what isn't factory, the washers in particular. I have a mixture of thin (0.5mm) wave washers, conventional (1.5mm) flat washers and standard split lock washers. The parts diagrams don't specify what kind of washers where originally fitted, my guess is the wave washers but parts are superseded multiple times over the years. Any suggestions?

    A little bit of a rant about hack work, The factory wisely marked every cap with a position number (1-20) and marked the head with a corresponding number so that the cap can accurately be replaced in it's original position. My caps on one head had been re-labeled multiple times by apparently less than knowledgeable mechanics either with number stamps or pointed punch. Mostly done next to the original numbers but in the opposite direction from the factory marks along the cam. Hack work, gotta love it.
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  2. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
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    Jan 11, 2001
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    +1 -- the amount of torque on those nuts is so low that you don't want a lot of that torque being lost into friction compressing the lock washer.
     
  3. Rifledriver

    Rifledriver Three Time F1 World Champ

    Apr 29, 2004
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    Split locks never on aluminum. Through the entire production run of 308, QV or 328 Ferrari used either very standard wavy washers or bellville washers.
     
  4. smg2

    smg2 F1 World Champ
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    Exactly.
    Given the harmonics and tQ I'd lean towards Belleville washers.
     
  5. fatbillybob

    fatbillybob Two Time F1 World Champ
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    Aug 10, 2002
    29,047
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    Wave washer was used there. Bellville are used in higher torque applications like preloading differentials.
     
  6. smg2

    smg2 F1 World Champ
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    I've lost track of how many camshafts I've pulled from the 308 engine series and I've never once seen a wave washer. Every single engine I've taken apart and rebuilt has had Belleville washers.
     
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  7. fatbillybob

    fatbillybob Two Time F1 World Champ
    Consultant Owner

    Aug 10, 2002
    29,047
    socal
    The ones that are on the cam caps are wave. That's what my old brain tells me. Belleville are the cup shape things
     
  8. smg2

    smg2 F1 World Champ
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    Yup, the cup ones are on the cam caps.
     
  9. Rifledriver

    Rifledriver Three Time F1 World Champ

    Apr 29, 2004
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    Earlier on they used wavy washers. Both worked fine assuming the guys in the engine room tightened them.
     
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  10. Rifledriver

    Rifledriver Three Time F1 World Champ

    Apr 29, 2004
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    By the way, you do know the V8s were bare aluminum, not painted?
     
  11. miked

    miked Formula Junior

    Feb 7, 2001
    898
    Cincinnati, Ohio
    So I have heard, my engine had paint on it as it came to me 25 years ago. It was peeling off in places so I cleaned it as much as possible and painted it again. If I ever rebuild the engine (this was more of a re-seal) I can remove the paint during that process.
     
  12. mk e

    mk e F1 World Champ

    Oct 31, 2003
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    Wave washers are thin and get stuck in the threads, I'm pretty sure they'd do more harm than good.

    I use flat washers for what little it's worth.
     
  13. Rifledriver

    Rifledriver Three Time F1 World Champ

    Apr 29, 2004
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    Well 40+ years of daily dealing with them I have not once seen harm done but I'll certainly keep a close eye on them.
     

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