Re: Shocks and springs for a '74 Spider

[Simon Favre <simon@domain.elided>]

The oscillations you feel are a result of too stiff a spring with not
enough damping from the shocks. Unfortunately, most shocks are designed
to have much less damping in compression than in extension. In order to
cure the oscillations, you would need to either put street springs in to
replace the race springs, or get some shocks that are more appropriately
damped for your particular setup. The old style Koni hydraulic shocks
(the red ones) can be re-valved. Just cranking them up stiffer only
changes the rate in extension (rebound). The compression damping is not
affected, unless you get double-adjustable shocks ($$$). In order to have
the red Konis revalved, you need to send them in with a detailed diagram
of the suspension, the typical weight on each wheel, and the spring rates.
It's a bit of a hassle to go through for a street car. If those really
are the race springs, not the street springs, perhaps the simplest answer
is to replace them. If you like the handling with these springs, the
simplest thing to do is get the red Konis and fiddle with the adjustment
till you get a decent compromise. In order to really make them work with
springs that are a lot stiffer, they would need to be re-valved so that
the compression (bump) rate is closer to the extension (rebound) rate.

Dave Pratt wrote:

>My '74 Spider has Ward & Deane racing springs, and KYB shocks, thanks to
>the PO.  The car is used strictly for the street.  It has the Ereminas 
>chassis stiffener and the suspension components are all in good shape.  
>The harshness of the ride isn't what bothers me - it's the, well, 
>oscillations that the car gets going over bumps.
>
>My feeling is that the KYBs, while in good condition, aren't matched to 
>the springs, and don't dampen the system properly.  So the questions are: 
>What shocks could I put on to address the problem?  Adjustables?  
>Anything else I should consider?  Anybody out there with experience with 
>W&Ds in a street application?

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