Re: [DML] Shocks - vendors and other scammers

[jwit6@xxxx]

In a message dated 6/9/02 1:05:58 AM Eastern Daylight Time, james@xxxx 
writes:

<< I'm just curious, and hope that someone can answer this for me 
intelligently. 
Wouldn't there be some disadvantage to using shocks from a FRONT engine 
car in the DeLorean application? I mean, think of the weight distribution in 
the 
DeLorean (35/65) versus either of the cars mentioned. Can someone explain 
to me why this is not factor? >>

James,
Shocks don't care whether they get to ride in the front or the rear. Shock 
absorbers absorb shocks. That is, they damp the movement of the suspension. 
They offer resistance to movement. The weight of the car is carried by the 
springs, not the shock absorber. ( Although on the DeLorean rear, since it is 
a coil over shock design, the spring does attach to the unsprung lower 
portion of the shock.) 

The more mass or weight that is set or put in motion, the more energy 
absorbtion required to keep the spring from returning the energy it has 
stored, back to the body and setting up a harmonic resonance (bounce). So 
when the suspension compresses, the inertial energy of the mass in motion is 
absorbed by the spring and the shock. Most of that energy goes up in heat. 
The rest goes into returning the car to it's normal ride height. 

So if you take a shock that offers a firm ride in it's original application, 
it will offer the exact same ride with the same weight, as long as the 
compression rate of the spring it's paired up with is the same as the 
original application.

So if you wanted to make a science out of it, once you know the dimension of 
the shock that fits the Delorean, you can take all the applications that run 
that dimension, find thier OEM spring compression rates, and the weight they 
were designed to damp. Then under the same conditions you'll get the OEM 
ride. A lot of work, and still a need to interpolate for DMC-12 applications 
(Do you want your car to ride like a Galaxy 500?).

For ball park purposes it would probably suffice to look at the amount of 
weight the shock was designed to damp, leave the spring out of the equation, 
and go with that. Shocks with a 1000 pound OEM damping load should offer a 
stiffer or less compliant ride in a 800 pound application.

Variable speed damping, or sensa track units should take a lot of the 
guess work out of it, since they should adjust thier damping to match 
velocity. Still a need to bolt it up and try it out to know what you're 
getting for sure. 

As always correct me if I'm wrong. We can all learn together.

Jim 6147