Bypass Valve replacement...any alternatives to the Capristo? | FerrariChat

Bypass Valve replacement...any alternatives to the Capristo?

Discussion in '348/355' started by DaisyCutter, Jun 15, 2015.

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  1. DaisyCutter

    DaisyCutter Formula Junior

    Jul 15, 2014
    255
    Sweden
    Full Name:
    Dayan
    While I repair the clutch fluid leak and with the bumper and muffler now off, I would like to sort the non-functional factory bypass valve on my '96 2.7. It is fixed open, I assume as it either failed or rattled.

    Is a replacement Capristo the only choice/best choice? Are there no reconditioning or upgrading kits available to bring the original back to life?

    Cheers.
     
  2. cf355

    cf355 F1 Rookie

    Feb 28, 2005
    4,208
    Full Name:
    chris
    The short answer is no.....unless you go to a machine shop and have them press out and replace the bearings. If you search you will find some posts where some members have sourced the bearings/replaced them and the valve worked fine.
    Its a lot easier just to go with Capristo but make sure you get the one with the heat shield as there were some heat related failures noted.
     
  3. cf355

    cf355 F1 Rookie

    Feb 28, 2005
    4,208
    Full Name:
    chris
    You mention that the valve is fixed 'open' (is it wired open? or seized). Sometimes if the valve is still functional but just starting to rattle you can adjust the nut on the shaft...add a little preload adjustment.
    Sometimes this is enough to stop the rattle......not sure for how long though.
     
  4. TrojanFan

    TrojanFan F1 Veteran
    Owner Silver Subscribed

    Nov 17, 2008
    5,182
    So. CA & NV
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    Peter
    #4 TrojanFan, Jun 15, 2015
    Last edited: Jun 15, 2015
    Anyone have any information on the bearings? I'm not finding anything on a search relating to the bypass and replacing the bearings. Just the ones about tightening the shaft. I have access to a press and am getting real sick of the rattle. I tried the adjustments with the shaft to tighten things up with no success. Also waiting on Goth to develop a reasonably priced replacement for the OEM (Hint, Hint).
     
  5. DaisyCutter

    DaisyCutter Formula Junior

    Jul 15, 2014
    255
    Sweden
    Full Name:
    Dayan
    I am not sure as of yet. One way or another I think the best long term solution is the Capristo. My wish is for the car to work right, the way was intended to.

    Thanks all for the feedback.
     
  6. DaisyCutter

    DaisyCutter Formula Junior

    Jul 15, 2014
    255
    Sweden
    Full Name:
    Dayan
    Is the heat shield the nicely finished metal outer casing of the vacuum chamber?
     
  7. mad dog

    mad dog Formula Junior

    Jan 5, 2006
    875
    suffolk uk
    Full Name:
    andrew
    I used one recommended on here and sold on ebay. It needed a bit of sorting to form a gas tight fit but not a major job and so much cheaper. I'll have a search around for that thread.
     
  8. cf355

    cf355 F1 Rookie

    Feb 28, 2005
    4,208
    Full Name:
    chris
    no, its an extra heat shield below the vacuum chamber
     
  9. cf355

    cf355 F1 Rookie

    Feb 28, 2005
    4,208
    Full Name:
    chris
    & if you can find the ebay listing....pls post the link
     
  10. 0.0.1.99

    0.0.1.99 Formula Junior

    Jan 14, 2012
    424
    Carolinas
    Full Name:
    Ken
    http://www.ferrarichat.com/forum/348-355-sponsored-bradan/391007-bypass-valve-has-balls.html
     
  11. cladd2000

    cladd2000 Formula Junior
    Silver Subscribed

    Jan 18, 2005
    519
    IMO it's not the "balls". I believe that the rattling sound is the butterfly flap rattling against the interior housing. The reason is that pre-load (from the vacuum valve) on the flap decreases over time. My solution is NOT increase pre-load by lengthening the shaft coming from the vacuum valve; it only works temporarily. Instead I believe in slightly SHORTENING the shaft so the valve is slightly open at rest and therefor does not rattle against the housing. But, to each his own!
     
  12. eyboro

    eyboro Formula Junior
    Silver Subscribed

    May 30, 2004
    989
    Chicago
    Full Name:
    Eitan
  13. f355spider

    f355spider F1 World Champ
    Owner Rossa Subscribed

    May 29, 2001
    18,053
    USA
    I would not replace it unless it is actually rattling...and if it is, then try the adjustment of the rod, that got rid of the rattle for me. I had another rattle later, that I could not find, on a hunch, tried the Capristo valve. It did not fix the rattle, it ended up being a baffle internal to my stock muffler. A Capristo muffler took care of that. The Capristo valve is nicely constructed though.
     
  14. eyboro

    eyboro Formula Junior
    Silver Subscribed

    May 30, 2004
    989
    Chicago
    Full Name:
    Eitan
    Adjusting the rod is not recommended, if you tighten the rod, the valve will not open.
     
  15. DaisyCutter

    DaisyCutter Formula Junior

    Jul 15, 2014
    255
    Sweden
    Full Name:
    Dayan
    Hello Hugh,

    I cannot guarantee that amongst the myriad of vibrations and buzzes emanating from behind me that the valve is indeed one of them. I don't think so though. It is my understanding that it rattles when it is closed so if that is the case I won't know until it is functional, if in fact it can be made functional again.

    I will pull it apart and find out its reason for seizure. If it can't be restored then I will order the Capristo.
     
  16. ClydeM

    ClydeM F1 World Champ
    Owner Rossa Subscribed

    Nov 4, 2003
    12,036
    Wayne, NJ
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    Clyde E. McMurdy
    Keep searching.
    there's threads on the bearings, replacing the diaphragm, and a Porsche valve alternative.
     
  17. f355spider

    f355spider F1 World Champ
    Owner Rossa Subscribed

    May 29, 2001
    18,053
    USA
    That was not the case for me, or a couple other local 355 owners. Only two or three turns adds enough force to prevent rattling. I suppose if one gets carried away then that could result in an issue...but then just back it off a tad.
     
  18. DaisyCutter

    DaisyCutter Formula Junior

    Jul 15, 2014
    255
    Sweden
    Full Name:
    Dayan
    Once I've got it back together I will see if needs some minor adjusting as described. Just enough to create a small amount of tension.
     
  19. 0.0.1.99

    0.0.1.99 Formula Junior

    Jan 14, 2012
    424
    Carolinas
    Full Name:
    Ken
    Not entirely a drop-in replacement but is very close. Typically you will need to notch the rear passenger side of the bypass valve frame to clear the lip of the factory (or even Tubi) muffler. Just search ebay for "exhaust control valve" and you will have many to choose from. Look for a 2.5" normally closed valve to mirror the factory operation (however Capristo is normally open I think). Good luck.

    Requires modification:
    Stainless Steel Exhaust Control Valve Set Vacuum Actuator 2 1 2" 63mm Pipe Close | eBay

    May not require modification:
    Exhaust Vacuum Valve with Vacuum Actuator 64mm 2 5" Closed Baffle | eBay
     
  20. Capristo Exhaust USA

    Capristo Exhaust USA Formula Junior
    BANNED

    Jul 29, 2009
    378
    Riviera Beach, FL
    Full Name:
    Capristo Exhaust
    If there are any questions about our product please do not hesitate to call or email. Thank you for the interest.

    All contact info is below.

    Thank you
    Erik Krammer
     
  21. Shootfighter65

    Shootfighter65 Formula 3

    May 13, 2014
    1,372
    Charleston SC
    Full Name:
    Randy..alluneedtokno
    wasnt there a member on here that rebuilt them? I cant remember his name because mine didnt need rebuilt so I just skimmed the thread
     
  22. TrojanFan

    TrojanFan F1 Veteran
    Owner Silver Subscribed

    Nov 17, 2008
    5,182
    So. CA & NV
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    Peter
    Anyone know anything about this second one? Valve comes from Cyprus so I would be very leery of sending them $300.
     
  23. Shootfighter65

    Shootfighter65 Formula 3

    May 13, 2014
    1,372
    Charleston SC
    Full Name:
    Randy..alluneedtokno
    Last I knew Jim Enterprises in China or Taiwan (they build the Fabspeed headers) sells one also I'm not sure on cost...
     
  24. 0.0.1.99

    0.0.1.99 Formula Junior

    Jan 14, 2012
    424
    Carolinas
    Full Name:
    Ken
    In addition to the valve though, $300 today buys you like 1/16 of the country as well. So go get 15 friends and you can own all the bypass valves. Just sayin.
     
  25. SoCal1

    SoCal1 F1 Veteran
    Owner Silver Subscribed

    Jun 14, 2011
    8,635
    SoCal LA/OC/New Mexico
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    Tim Dee
    I tried the first one works fine

    Never tried the second, pay with payapl, no issues if any problems

    I buy worldwide daily and usually better then buying here in the states, I get my Bosch stuff from Romania in like 3 days. faster then my Bosch Distributer
     

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