Date: Fri, 19 Jun 1998 16:14:34 -0400
Reply-To: Derek Drew <drew@INTERPORT.NET>
Sender: Vanagon Mailing List <Vanagon@vanagon.com>
From: Derek Drew <drew@INTERPORT.NET>
Subject: Re: Pre-loading Rear Springs re Syncro Suspension (long)
In-Reply-To: <358ABC94.6A8E4391@Schwenk-Law.com>
Content-Type: text/plain; charset="us-ascii"
At 12:31 PM 6/19/98 -0700, you wrote:
>Derek Drew wrote:
>
>> <> what do the spacers do that firms up the
>> > suspension if they do not change spring rate?
>
>> I believe there is a possibility the spacers may not actually firm anything
>
>> up at all.
>>
>
>Well, if that's the case, then the placebo effect is remarkable and well
worth the
>effort in any event. :~0
>
>I think I see where theory departs from reality. Your theory assumes that
the
>spring length remains identical with and without the spacer, and that all the
>spacer does is increase the height of the van by the distance of the
thickness of
>the spacer.
Right. You have my assumptions correctly. If I am wrong, you likely right
in some other respects that I previously suggested you might be wrong about.
>I think that the spacer lifts the van some, but I also think it compresses
the
>spring a little too.
I could imagine this, but theoretically there must be something extra in
the mix to cause this, because the weight on the springs is the same either
way, and therefore they ought to be the same length either way.
>The result is that with the spacer, the spring is slightly
>more compressed ... it is pre-loaded... over what it would be without a
spacer ...
>with the same weight in the van, etc. Assume this to be true, and that the
>distance of additional compression is 1 cm....i,e, the spring is 1 cm.
shorter
>with the spacer than without when installed in the van with the van
sitting on a
>flat surface.
>Doesn't it take more pressure to compress the spring the next 1 cm. than
it did to
>compress it that first 1 cm. accomplished by inserting the spacer?
yes, you are right to postulate as you have in the previous sentence
>When you compress a spring, the force required to compress the spring is
not the
>same all the way to the point where the coils bind, is it...even in a
progressive
>rate spring? So, if you shorten the spring by compressing it a little,
aren't you
Yes. I just don't know that I believe the spring is compressed very much by
the doughnuts. I suppose it is possible, but the *only*way to compress
those springs further is by extra weight, and I don't see how the doughnuts
would cause extra weight to be loaded on top of the spring points except at
that point that the vehicle has reached its maximum shock travel.
>making it a little stiffer since it requires more force to compress it
further
>than it would have required to compress it the same distance had you
started with
>a completely un-loaded spring?
>
>steve
>
_____________________________________________________
Derek Drew New York, NY & Washington DC
ConsumerSearch
drew@interport.net
212-580-6486 (W)
212-580-4459; 202-966-0938 (H)