RE: Coilovers vs. Shocks/Springs/Struts

[Khan Klatt <khan@mediaaccess.com>]

Perfect explanation-- that makes sense. Yet what is the difference 
between jumping and hoisting, except that in hoisting the weight is 
taken of gradually and nonviolently (ideally anyway) and jumping is 
abrupt...

Also, the spring is apparently rigid enough not to buckle... imagine 
a floppy spring like a slinky... it's hard to keep it straight along 
it's central axis (i.e. the axis from which the radius of the coil of 
the spring would be determined)...

Of course, if it buckled at all, it would scrape along the strut 
anyway, and the strut would keep it in place...

But it seems to me the springs are pretty darn hefty, even without 
the strut keeping it in place. All very interesting.

-K

At 11:31 AM -0700 04/10/2000, Belt, Stephen D wrote:
>Khan-
>
>The coil isn't fixed in place.  It isn't attached in any way.
>Compression and weight are all that holds it in place.  On my
>Dodge Ram, there isn't even compression, just the weight of the
>vehicle.  On the spring perch is a rubber gasket that's about
>1/2" thick that provides some adhesion and noise reduction.
>
>I know this probably makes it sound like the spring should be
>moving all over the place, but with several hundred pounds
>pressing on it all the time, and with the way that the upper
>mount point is fixed and the lower point is allowed to move
>only vertically (never side to side, unless ball joints are
>extremely worn), the spring doesn't need anything further to
>keep it in place.
>
>On many vehicles, catching air is a problem, as the suspension
>system is not really designed with this in mind (jumping, that's
>is, not hoisting).  When jumping, the suspension uncoils very,
>very quickly.  Whatever suspension element limits maximum droop
>will undergo an extreme stress.  Often that element is the shocks
>as they expand to their maximum point.
>
>You may notice that some 4x4 trucks that want to jump will have
>limiter straps added to the system, to address this problem.
>The strap keeps the spring from fulling releasing, and perhaps
>moving from its intended location on the spring perch, and from
>the shocks being the droop limiter and inadvertantly breaking a
>shock.
>
>Steve Belt - Scotts, AZ
>1998 VW Jetta GLX


Khan Klatt                                         khan@mediaaccess.com

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