The springs carry all the weight that is bearing on the top of the springs.
Call it chassis - call it body - call it whatever you want to call it.   The
chassis and body are rigidly attached to one another.    The only weight the
springs do not support is the weight of the components that contact the bottom
of the springs.    Since the Vanagons and Syncros have independent suspensions
front and rear, I would suspect the unsprung weight of the Syncro is about the
same as the other Vanagons.    The only difference would be up front, with the
CV joints and associated unsprung front wheel drive components   The transaxle,
drive shaft, front differential, etc. are all attached to the unibody
frame/chassis.

Wendell Hovey

"James S. Cohen" wrote:

> All,
>
> I got the SA Heavy Duty springs measured today. The fronts were 500lbs/in.,
> and the rears were 280lbs/in.
>
> I did not get a chance to remove the stock springs from one of my "herd" of
> Vans, so I don't know how much stiffer these really are.
>
> I'm somewhat skeptical of the device this guy used to measure the rate
> however. It was VERY old, and beaten up. I have NO idea if he ever
> calibrates it.
>
> It's probably accurate for springs tested on IT. I dont' know if it has
> relevance to springs tested on another tester somewhere else in the country.
>
> I'll take the stock springs off and get them tested next week.
>
> Also, my book on chassis engineering clearly states that the springs ONLY
> support the weight of the body, and the weight of the chassis is
> irrelevent. Therefore, the extra weight of the syncros is not borne by the
> springs since it's on the chassis.
>
> So, it would seem, that syncros don't need spring rates any higher than a
> 2wd although they may need LONGER springs.
>
> If anyone disagrees with this, feel free to open a thread to debate it!
>
> I'm NOT an expert on springs, I have read books, and have experience with
> my GTis and Corrado. So, if there ARE any experts, let's hear from them.
>
> Meanwhile, I'll consult some of the racers on my other lists, and see what
> they say... (of course, this is all rather moot since there are only a few
> springs even available for the Vanagons) ;)
>
> James

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