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consistency and tuning questions

Discussion in 'Ask The Pros' started by JamieM, Apr 8, 2019.

  1. JamieM

    JamieM Pinewood Ninja

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    I could use the collective expertise this forum offers. Here goes.

    Stock district races this past weekend where we built 2 plug and play, 4 wheel, no bent axle, and followed John's black ice prep, polished BSA axles to 5k, pledge then graphite. COG was .5" which contributed to some less than straight runs but nonetheless finished first and second respectively.

    My question is: their times fluctuated by a big margin and I'm wondering if it was more a track or car issue. Here are their times on a 35' 4 lane Best Track.

    Lions Car 1 - average time 2.56575 finished first
    1. 2.5713
    2. 2.5502*
    3. 2.5673
    4. 2.5684
    5. 2.5719
    6. 2.5617
    7. 2.5724
    8. 2.5628

    Webelos Car 2 - average time 2.57305 finished second
    1. 2.5518*
    2. 2.5804
    3. 2.5788
    4. 2.5812

    This is our first run using a ladder high-performance car from DD4H and in fact, the tune was pretty aggressive 6-8" at 48" and I thought I could get away with that low a COG. The track seemed rough and the deceleration section would cause the car sometimes to get airborne and they had a box at the end with rigid foam to absorb impact. Rather disappointing and debating if new cars will be needed for Nationals.
     

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  2. Reecedad

    Reecedad Council Champion

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    Did the car wiggle?
     
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  3. JamieM

    JamieM Pinewood Ninja

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    Yes
     
  4. Wolfram Racing

    Wolfram Racing Rail Runner

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    Too aggressive on the COG? Sounds to me that you are on the border between stable and unstable...a rough track isn't going to help that situation at all.
     
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