355 bypass valve wired open ? | FerrariChat
Buy

355 bypass valve wired open ?

Discussion in 'Technical Q&A' started by spiderscott, Dec 20, 2004.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, Skimlinks, and others.

  1. spiderscott

    spiderscott Formula 3
    Silver Subscribed

    Feb 24, 2004
    1,662
    Ratarossa HQ UK
    Full Name:
    Ratarossa
    #1 spiderscott, Dec 20, 2004
    Ive got soooooo fed up with the vibration from my exhaust valve even thought it is brand new, anyway in my last post someone suggested wiring it open, which I have just done ...... must say im impressed it sounds great !! not only has it got rid of that terrible rattle noise but the exhaust sounds deeper (this could just be my ears hearing Ferrari exhaust music instead of rattle!!).

    Couple of questions regarding having it wired open:

    First will this have any knockon effects with the car, a friend has just told me that Maranello advise againist doing this as it causes Cat problems .... ????

    Second will this use more fuel ??

    Any other drawbacks ??

    Can anyone explain what the bypass valve actually does ?? .... might help me understand why opening it could cause Cat probs.

    Thanks
    Scott
     
  2. jh355

    jh355 Formula Junior

    Feb 12, 2004
    424
    Halluci-Nation
    Full Name:
    Craven Morehead
    #2 jh355, Dec 20, 2004
    It’s possible your EBV is either;
    1.) Adjusted incorrectly (allowing the valve to flutter from idle to 3k).
    2.) Spring has been overheated and is weak (allowing the valve to open under 3k rpm) (pre 98 spring 4lbs @ 1.0” post 99 springs 8lbs @1.0”.
    3.) The end cap bearing has been blown off (allowing the valve to buzz at pick your favorite RPM usually 2400 rpm).

    Wiring the EBV open will increase the HP just like leaving off the Air filters, but neither can be healthy for the motor long term.
     

Share This Page