Getting the back half of the rear main.

Discussion in 'PSI Superchargers Tech Questions' started by tsegars, Jun 22, 2015.

  1. tsegars

    tsegars New Member

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    im having trouble wiping the back half of the rear main and it just started this year. It's a clutch car and seems to only do it when I shake the tires but I haven't had this problem until this year. I've tried two different motors and wondering if maybe someone else has had this problem. It's a titanium clutch, bontifonti, and titanium flywheel, in a promod car. I've already started oiling with the other oil gallery and it may have helped but it didn't fix it.
     
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  2. jay70cuda

    jay70cuda Well-Known Member

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    What's the line bore look like. I've seen this happens when line bore gets off. If it's right on the. You could open the rear main up .0005 should do it. Is it a 3 disc by chance. I e seen guys have to put top fuel rub blocks on the back to keep the crank from flexing so bad. I have 11in 2 disc never had a problem with rear mains ever.
     
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  3. SoDak

    SoDak Active Member

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    We've done this many times in our BBC's before we traced the issue to clutch imbalance.

    There are many places "clutch imbalance" can come from;
    -floaters that have ears that are wore
    -stands that are wore
    -flywheels that are warped (the more discs you have the straighter these need to be)
    -pressure plate (not sure the name) ears that are wore

    The higher the RPM the more important these items are.
     
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  4. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    clutch

    95% of rear main problems are clutch related.

    First thing to check is put a straight edge across the back of the flywheel.

    If you are not drilling your floaters, many teams will drill in a standard location (make a fixture). I have seen this location vary from in the middle of the floater to up on one of the ears. In a 3 disc clutch, you would stagger where the holes in the floaters are (one at 12, one at 6). This keeps both floaters from getting heavy on the same side.

    I would also check to make sure your stands are straight as well.
     
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  5. tsegars

    tsegars New Member

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    Thanks for the information I'm looking at the clutch.
     
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