the pads roughly 3/8" thick little round 'hockey pucks'.
The ones that came of the old spring were as fat as the leaf spring
locating dimple is deep ( < 1/8") and now looked like 'top hats'
with the brim less than 1/64" thick.
About 1/4 of the volume of rubber making up the 'puck'
had been compressed and squeezed out to the sides.
...Figure 3 pucks... 1/4" each that's 3/4" lift in the loaded position of the
spring!
After going through this whole 'test' ,.... I replaced the entire spring.
...Why? Because I had one laying around.
I figured I was under there, might as well put it in.
Paul Tegler
1973 BGT - Daily Driver
Rat - 1980 Spitfire w/ O/D - in re-hab
Punkin' - 1978 Spitfire - in Superb Shape!
email: wizardz@toad.net http://www.teglerizer.com
-----Original Message-----
From: Simmons, Reid W <reid.w.simmons@intel.com>
To: 'wizardz' <wizardz@maxinter.net>; spitfires@autox.team.net
<spitfires@autox.team.net>
Date: Wednesday, September 15, 1999 3:15 PM
Subject: RE: Spring sag on one side (bear with me it's a little lengthy)
Paul;
This sounds like the simplest, lowest cost solution I have heard so far. I
do have some questions though: Did you compare the old rubber pads with the
new ones? Did you see enough difference in the pads that would account for
at least the majority of the sag? Have you had this fix in place long
enough to determine that this is the "cure" (until the new pads wear out and
need to be replaced)?
Thanks
Reid
'79 Spitfire (original owner)
-----Original Message-----
From: wizardz [mailto:wizardz@maxinter.net]
Sent: Wednesday, September 15, 1999 7:06 AM
To: spitfires@autox.team.net
Subject: Re: Spring sag on one side (bear with me it's a little
lengthy)
To correct the 'lean' ...one way around it is as follows.
Replace the little rubber pads that fit under the ends of the leaves
JUST on the driver's side (at first at least)
VB sells the little rubber pads for $1.95 each
(99 summer catalog page 120 #0-030 $1.95 each)
you'll need three per side (six for the whole spring)
2 reasons for driver's side only (at first anyway)
1) they are the ones worn out (most likely)
2) it'll make up for the hieght problem associated
with the 'worked in' side of the spring
You can replace them without even removing the spring from the car
Jack up the whole rear end. Drop the driver's side rear wheel.
Use a jack to support the wheel/bearing/upright assy at the wheel
adjust the hieght as nessesary to remove the top vertical upright link bolt
Don't let the axle wieght 'hang' on the brake line.
using a c-clamp to keep the leaves compressed as needed
and a chisel/screwdriver/wood wedge as a shim, you can remove the little
clamps that hold that stacks together and spread the leaves
enough to slip in new pads.
It only took me an hour and a half... and my '80 sits perferctly level now.
Paul Tegler
1973 BGT - Daily Driver
Rat - 1980 Spitfire w/ O/D - in re-hab
Punkin' - 1978 Spitfire - in Superb Shape!
email: wizardz@toad.net http://www.teglerizer.com
-----Original Message-----
From: Vic Whitmore <vicwhit@home.com>
To: Joe Curry <spitlist@gte.net>
Cc: Barry Schwartz <bschwart@pacbell.net>; spitfires@autox.team.net
<spitfires@autox.team.net>
Date: Wednesday, September 15, 1999 9:18 AM
Subject: Re: Spring sag on one side (bear with me it's a little lengthy)
I tend to agree with Joe on this one.
Although Barry puts up a convincing argument, the swing spring balances on
the
mid point (I think we all agree). It will reach an equilibrium when the
weight
applied on each end is equal. If one end is slightly weaker, spacers worn,
or
deformed due to heavier use (e.g. driver side), it will deflect a greater
distance until the applied force is equal to the opposite end. You would
then
end up with one side lower than the other.
To illustrate this, take this to the extreme. Consider one side of the pivot
to
be totally rigid (e.g. steel) and the other flexible (e.g. plastic). With no
weight applied, it would still balance on a pivot point (assume each side is
equal weight). Add equal weights to each end, and the arms will balance out
but
one will be significantly lower than the other. One problem with this
example is
that the arm with the greater deflection (plastic) will also have a shorter
moment-arm due to a decreased distance from the weighted point to the pivot.
Since the deflection in the rear spring is so small, this shouldn't be a
factor
in real life.
Now for the engineering types, let's have some of the math with spring rates
and
moment arms and all such stuff included in an equation. Or not...
Vic Whitmore
76 Spitfire
Thornhill, Ontario
Joe Curry wrote:
>
> Barry,
> The Swing Spring is weaker than its predecessor (the fixed spring) and
> because of this, and the fact that it flops from side to side, it IS the
> major cause of most sags in late Spits.
>
> Take a look at early Spits and see how many (that have not been
> converted to swing springs) show evidence of this sag.
>
> It's my opinion, based entirely upon comparison of the two types of
> suspension that the swing spring is indeed the cause. It has fewer
> leaves and therefore when the car has weight continuously applied
> unevenly (driver only) it will sag long before an equivalent fixed
> spring model.
>
> Compounding this of course is the greater negative camber of the longer
> axles which seems to me to make the applied weight rest more on the
> spring.
>
> Regards,
> Joe
>
> Barry Schwartz wrote:
> >
> > >"My Spit (like so many others) has a definite lean toward the driver
side of
> > >the car.
> > ***********************************
> > I've read several listers complaining about one corner of the car
sitting
> > lower than the other over the past few weeks, and the general consensus
is
> > to blame the Swing Spring. I can't see how the rear spring, in a
Spitfire
> > with a SWING SPRING, can CAUSE this problem. I feel that this poor
spring
> > is getting a bad rap, and I believe that it is undeserved. My own
opinion
> > is it is a very CLEVER and elegant solution, given the constraints at
the
> > time to solve a potentially serious problem. Overall rear end sag from a
> > worn spring, yes and this is evident with any well worn rear spring, but
> > side loading is virtually impossible by it's very design. It may not
> > counter an exiting leaning/listing condition by something else that is
> > causing the lean, and therefore, these vehicles may be more sensitive to
> > the problem but there is no roll or side to side loading with a swing
> > spring except from the main leaf itself, and that would be a very small
> > amount indeed. It's conceivable that a bad main leaf (however unlikely)
> > could cause a slight list, but I contend it would be very slight. The
> > other spring leaves are, if all is functioning correctly, and in good
> > order, FREE to rock about the diff center, and do nothing as far as
biasing
> > the car on it long axis. You could cut one of the leaves off one side
> > (provided it was not the main one) and all it would do is cause the
entire
> > rear end to sag a little more. The way this spring is designed it CAN'T
> > cause a "roll" bias, because the action is "divided" between the two
> > wheels. If one were to imagine, for illustrative purposes, that you had
no
> > front wheels or roll bar on the car. Place a pivot under the front cross
> > member directly at its center to support the weight at the front end,
but
> > allowing it to rock about that pivot. The only thing now keeping the
car
> > level, with respect to roll, would be the main rear leaf itself, and if
> > just that spring leaf was removed, (and all others were to remain in
place)
> > then it would roll over to one side or the other "pivoting" as it were
on
> > the center bolt in the spring clamp assy. That's the very premise of
this
> > design. Now you can see, that the remaining spring leaves do NOTHING to
> > cause the car to lean or list in one direction or the other. So I say
> > (for what it's worth) if your car is experiencing a tendency to lean to
one
> > side or another, look elsewhere (possibly the rubber pad p/n 149191
UNDER
> > the clamp if you must look at the rear), not at the Swing spring-
> >
> > Barry Schwartz (San Diego) bschwart@pacbell.net
> >
> > 72 PI, V6 Spitfire (daily driver)
> > 70 GT6+ (when I don't drive the Spit)
> > 70 Spitfire (long term project)
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