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308 Wheel bolt to stud conversion

Discussion in 'Technical Q&A' started by pma1010, Jun 17, 2005.

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  1. pma1010

    pma1010 F1 Rookie

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    Philip
    #1 pma1010, Jun 17, 2005
    My guess is most 308 owners take the wheels off the car once a year. Over the last couple of years, mine are coming off and going on again with high frequency from corner weighting, changing wheels, rotating tires and so on. The threads in the hubs are getting worn. I have just ordered, and will replace, one front hub and will inspect the other.

    The longer term solution is likely to replace wheel bolts with studs and use an appropriate nut. I know the 360 Challenge cars did this and believe the 355C were similar.

    Searching the archives there are two threads that deal with the issue, usually in the context of the 355C question, but also where larger wheels (360, 550 etc) are mounted on 308s (which has raised its own set of issues).

    Anyone BTDT on a 308? If so, where did you source the studs and nuts? One further source of complication, I use a ball (rather than a tapered) wheel bolt which has a "shoulder" and accepts a 17mm socket head so an OEM sized nut will not fit. That said, the studs may work.

    If I need to source from other than Ferrari, I believe Volvo used the same bolt pattern (5x108) on the wheels. Does anyone know if Volvo used a 14 x 1.5 mm nut/bolt/stud?
    Thanks
    Philip
     
  2. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
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    #2 Steve Magnusson, Jun 17, 2005
  3. pma1010

    pma1010 F1 Rookie

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    #3 pma1010, Jun 17, 2005
    Thanks Steve. I had ordered bolts from them before but not looked at any conversions. As I read this and other sites, there are two types of wheel studs, press fit and threaded. I am assuming a threaded stud with some red loctite is the way to go, but want to check from others that have been down this path before attempting given both the heat (brakes) and torque (air guns) placed on the studs/nuts.
    Philip
     
  4. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
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    #4 Steve Magnusson, Jun 17, 2005
    The attachment method of the stud to the hub will be the tricky bit. No experience for me with them (I just recalled that bolt-to-stud conversion stuff was listed there from surfing their website after "Big Head" Dennis mentioned them on FList in the Elder Days) -- let us know the details/options/responses you uncover.
     
  5. Artvonne

    Artvonne F1 Veteran

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    #5 Artvonne, Jun 19, 2005
    Its been my experience that most wheel studs are a press fit in the hub coming in from behind, but you guys already probably know that. I just dont know what kind of clearance there is behind it. I had already been thinking about this, as while some may hate ignition points, and I dont, I absolutely cant stand wheel bolts. I cant even comprehend why a car maker would have ever considered them. While a press fit stud would most likely make the hubs forever unable to return to stock, I would imagine a thread in stud with bunged up threads and locktite should hold up fairly well and allow us to use more logical wheel nuts, no? Many thread in studs have a middle area that is not threaded, so maybe that could be brought down tight into the hub with a stud driver and if clearance were needed the back side could be ground away. If clearance exists, perhaps a locknut could be threaded on the back side and tack welded? Perhaps a "thin" nut? Again, I have no idea what kind of clearance exists behind the hub. I will be changing rotors soon, so I will take a look and see what may be possible.
     
  6. pma1010

    pma1010 F1 Rookie

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    #6 pma1010, Jun 19, 2005
    ECS Tuning sells threaded studs in different lengths and nuts for same (taper or ball). They put on with red loctite.

    There is clearance on the back of the front hubs to use a locknut if needed.
    The rears do not have sufficient clearance for same.

    I imagine the Challenge conversions used a threaded stud. Can anyone confirm? Also, loctite or some other fixing method.

    A press fit stud would require drilling at say a 36 degree offset (although any would suffice).

    While nothing is impossible, I suspect the hubs are hard to weld given they are cast (porous).
    Philip
     
  7. Smiles

    Smiles F1 World Champ
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    #7 Smiles, Jun 20, 2005
    I'd feel a lot more confident on the track with cottor pins, or at least safety wire, securing the wheels to my car than I would with Loctite alone.
     
  8. don_xvi

    don_xvi F1 Rookie

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    #8 don_xvi, Jun 20, 2005
    Loctite, lock nuts, etc are really not necessary to hold the studs into the hubs. They're held in the threads of the hub just as the nut is held on the end of the stud, by the tension in the stud. Unless you feel the need to loctite the nuts on the stud, or even the current bolt into the hub, you don't need to loctite the stud. No problems no my MB in 30,000 miles using studs in the summer.
     
  9. pma1010

    pma1010 F1 Rookie

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    #9 pma1010, Jun 20, 2005
    For the 355 Challenge manual extract. Screwed stud. Has a flange on the hub side to form a natural barrier/tightening surface.

    Oh the fun news, $100 for the stud, $60 for the nut from Ferrari. ECS Tuning sells a combination (w/o flange) for about $10/stud-net combination. I could get sets custom made for less. Got to love that F1 developed pricing scheme. Nuts. literally and figuratively.
    Philip
     

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