[Bob Bidonde]

History,

My cars have reproduction springs in the front damper, and I suspect that the reproduction springs are not as stiff as new originals. I do not have access to the drawings for the original springs, so I do not know their spring constants.

Using the reproduction springs, I tighten the nut just enough to engage the coil springs. Then I drive the car sensing vibrations and clutch chatter. I continue tightening the nut and test driving the car until I get what I feel is the preload on the damper that is best for my driving style. If there is no tuning I can live with, I would replace the coil springs with stiffer ones and continue testing. Such is the case with my Victoria, it needs stiffer springs in the front damper.

Here's another thought. Running a high compression head increases the reciprocating force which adds to the vibratory force. Lightening the flywheel and clutch changes the rotating unbalance, and the seesaw effect about the rear engine mounts. The seesaw would have more unbalanced engine weight for the damper to balance.

The bottom line is that the vibrations don't go away, they just change their amplitude / frequency. We seek small amplitude and high frequency in the Model "A."