BAE Exhaust valves bending

Discussion in 'PSI Superchargers Tech Questions' started by smbs, Dec 24, 2007.

  1. smbs

    smbs New Member

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    Is anyone having valves bend for no apparent reason? There is no contact with piston. 12 runs on exceldyne and 6 bent.
     
    #1
    smbs, Dec 24, 2007
  2. eli

    eli Banned

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    #2
    eli, Dec 24, 2007
  3. Alkydrag

    Alkydrag Sr. Dragster

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    Valves just don't bend for no reason. Take a harder look, I'll bet you find witness marks on the edge or the face of the valve. Look for smiley faces in the valve pockets. What is the centerline of your cam?
     
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    Alkydrag, Dec 25, 2007
  4. smokinboyz

    smokinboyz Member

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    Uri Geller Doin The Tune Up???? Merry Xmas
     
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    smokinboyz, Dec 25, 2007
  5. Mike Canter

    Mike Canter Top Dragster
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    We used to get bent exhaust valves after a run when we had a nitrous motor. It was only the exhaust valves that were open after shutdown and cool down. It was due to drooping from heat. We switched to inconel exhaust valve and never had another problem.
     
    #5
    Mike Canter, Dec 26, 2007
  6. nitrohawk

    nitrohawk New Member

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    If you are currently using titanium exh valves they will bend with to much heat. Titanium melts at 1200 degrees F. It has been my expierence that anything close to that and the valves will show bad on a leak test.
    Other than that if there are no marks on the pistons take the intake and headers off turn the engine over on #1 to TDC in the overlap and take a flashlight and observe how close the valves are to touching. You might have to check at 10 degrees befor and 10 degrees after TDC also.
     
    #6
    nitrohawk, Dec 26, 2007

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