I am trying to cure a wheel hop /tramp issue in an IRS sedan. The cause seems to be a resonance issue from the wheel spin / then traction twisting of the rear axles. The new 2010 Camaro solved it by using different axle sizes left to right, as did the Cadillac CTS-V. The frequency of the tramp seems to be around the 6Hz range. Problem is complicated by using Koni FSD dampers that use a tiny oil pump that after a few oscillations, results in a rebound hole opening and rebound force decreasing for ride comfort ...hence frequency damping is reduced on rebound for a selection of frequencies approaching 10Hz (hitting holes at a fast rate). I feel that this reduced rebound force is making the tramp worse (let's agree to call it tramp, under acceleration). Any thoughts before I try different rebound settings? Fabricating new axles is the main aim, but this rebound issue is stopping progress.
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