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  1. #1

    where did my rpms go???

    April 8400 15/20 78.7
    May 8380 15/20 77.5
    2 Days Ago 8200 75.1
    Today No Changes 8000 15/20 73.5
    It Has Racing Cam, Rr Level 1, New Rr Sc Impller, Ported Head, Nils Springs, Seat Hight In Front On One Valve Is High But Valve Was Cut To Cominsate. Boost Is At 9lbs At 8000 Today
    Compression Front 115 Middle 125 Back 125

    Can My Cam Be Off 1 Or 2 Teeth I Also Know Humidity Is So Vital But I Need And Have To Be At 8400rpms

    What Will Take


  2. #2
    75 mph on a budget TorquePhoto's Avatar
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    is it safe to asume with those mods you have ditched the ceramic SC washers??? You posted that you are seeing 9psi, is that normal for 8k with your setup??? This smells of SC troubles....



  3. #3
    Moderator Franko's Avatar
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    Your boost is a little low for the RR SC impeller, so my first thought would be to check the clutch slip moment. Might need a shim. After that, then the cam timing might come into play, but since you have seen 8400 RPM in the past, I would doubt that is your problem. Of course, heat is the obvious variable. What prop are you running?

  4. #4
    EZ Dock of Long Island Shibby1485's Avatar
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    i think your RPMs went out the exhaust pipe with all the oil and blow-by bc yo chit is gone bye bye just playin, i hope

    weird tho... nothing unchanged and just a steady loss of RPM? or have u been tinkering with things?

  5. #5
    Moderator two2curupt's Avatar
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    do a leakdown test

  6. #6
    Got Boost? psycho rxp's Avatar
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    Definately sounds like it's time to shim the SC clutches (if they are the metal ones) I had the same problem, and the slip was on the low side. 1 more shim and it's back on the limiter.

  7. #7
    i think its the cam timing sincei have just put the head back together. it may be off 1 tooth im going to change the slop first and see if i get higher compression.

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