[DeTomaso] Aldan shocks help!

pantdino at aol.com pantdino at aol.com
Tue Mar 23 00:24:40 EDT 2010


Oops. My bad.
I will never again post anything regarding springs or shocks
Please ignore my other post, which was sent before I read this one.

Jim






-----Original Message-----
From: MikeLDrew at aol.com
To: pantdino at aol.com; tonydigi at optonline.net; panteratime at aol.com; detomaso at realbig.com
Sent: Mon, Mar 22, 2010 9:14 pm
Subject: Re: [DeTomaso] Aldan shocks help!



In a message dated 3/22/10 21 02 27, pantdino at aol.com writes:



I'm not sure if its just terminology that we differ on, but here's my thinking:

The spring holds the car up.
The bottom of the spring rests on the suspension arm, which is directly attached to the wheel. So it is fixed in height.
The longer (taller) the spring is the higher the car will sit above the ground.
So screwing down the adjuster to make the spring shorter (compress it) will lower the car closer to the ground.

I'm not sure if its just terminology that we differ on, but here's my thinking:

The spring holds the car up.
The bottom of the spring rests on the suspension arm, which is directly attached to the wheel. So it is fixed in height.
The longer (taller) the spring is the higher the car will sit above the ground.
So screwing down the adjuster to make the spring shorter (compress it) will lower the car closer to the ground.


>>>That's exactly wrong.

The bottom of the spring doesn't rest on the suspension arm.  It rests on the bottom spring perch, which is fixed on a conventional (stock) shock, and is adjustable height on any aftermarket shock.  The height of the spring is basically constant, regardless of where the spring perch is.  The free length when the car is in the air and the suspension is hanging free, let's say, will be 10 inches.  If the distance between the upper and lower perch is less than 10 inches, then the spring will be slightly compressed.  Regardless of whether the spring is slightly compressed by the adjustable perch or not, when the weight of the car is placed upon it, it will compress to a fixed length due to the weight of the car--for sake of argument, let's say it compresses to 6 inches.

If the spring perch is lowered all the way down, then the bottom of the spring will be closer to the ground, and the top of the spring (and the car) will be a fixed height above that.  If the spring perch is raised all the way up, then the bottom of the spring will be further away from the ground, and the top of the spring (and the car) will be the SAME fixed height above that.

Lowering the spring perch lowers the car and raising it raises the car.  It's that simple.  It doesn't matter if, when the car is in the air, the distance between the upper and lower spring perches is greater than, equal to or lesser than the free length of the spring.  The spring will compress to its natural compressed length when the weight of the car is placed on it, and that length will remain constant as long as the weight of the car remains constant.  The only variable is the location of the bottom spring perch (since, in adjustable shocks, the upper perch is normally fixed--although the shock can be inverted and the same principle still applies).

Mike 



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