MSD 8973

Discussion in 'PSI Superchargers Tech Questions' started by WIDEOPEN231, Apr 30, 2017.

  1. WIDEOPEN231

    WIDEOPEN231 Member

    Joined:
    Jun 10, 2011
    Messages:
    112
    Likes Received:
    17
    MSD 8973. Have read cpl articles about problems with earlier models and wondering if still exist with newer models/ Asking because helping TA/D team and have been hurting some parts w/o real explanations. Two pistons cooked and data shows temps too low to be hurting anything. Examining all avenues of possible cause.
     
    #1
  2. GTPerf

    GTPerf Member

    Joined:
    Oct 22, 2006
    Messages:
    204
    Likes Received:
    5
    Have ran them for years never 1 problem, I have 2 , 1 never used was bought incase we had trouble.
     
    #2
    TADHemiracer likes this.
  3. TADHemiracer

    TADHemiracer Member

    Joined:
    Dec 9, 2010
    Messages:
    359
    Likes Received:
    14
    I doubt that the 8973 is the problem. Sounds to me that the EGT reading are too slow or are incorrectly placed. Either way, reading the plugs may help you and don't rely on EGT.
     
    #3
  4. Mike Canter

    Mike Canter Top Dragster
    Staff Member

    Joined:
    Mar 10, 2004
    Messages:
    4,630
    Likes Received:
    189
    I have never seen a 8973 mess up. Normally the cause is from using an unshielded or ungrounded shielded crank trigger extension cable to the 8973 from the crank trigger. The extension cable acts like an antenna to the high voltage spark to the plugs and in turn this randomly triggers the 8973 into firing. It can look just like detonation or a timing problem and can destroy a motor.
     
    #4
  5. WIDEOPEN231

    WIDEOPEN231 Member

    Joined:
    Jun 10, 2011
    Messages:
    112
    Likes Received:
    17
    I always go by plugs and use egt as back. Slow read is another issue. Owner was talked into computech datamax instead of racepak,not by me either. Also looking into pump as possible problem. Enderle 1275,yea need lil bertha.

    Will have to check on shielding for crank trigger.Having car 100 miles away makes things little more difficult. Still racing blower deal more fun than bracket crap.
     
    #5
  6. Mike Canter

    Mike Canter Top Dragster
    Staff Member

    Joined:
    Mar 10, 2004
    Messages:
    4,630
    Likes Received:
    189
    Even if that crank trigger cable is shielded it cannot be routed with other cables and has to be kept far away from the coil wire and the plug wires.
     
    #6
  7. aj481x

    aj481x Member

    Joined:
    Jan 27, 2004
    Messages:
    976
    Likes Received:
    18
    Grounding hasn't been mentioned yet, must be head to head to coil ground.
     
    #7

Share This Page