I just finished a front supension 'performance rebuild' and though I might
as well bore the list with the details.
My kingpin was still in good shape because I had rebuilt the front end 4
years ago. At that time I had neglected to change A-arms and only
installed new fulcrum pins. Now I was back to massive play in that area.
After reading some instructions by Dave Formstone on this list, I decided
to rebuild the A-arms myself. Apple Hydraulics, makers of leaky shocks,
has the fulcrum bushings for $16/side. They will rebuild your arm for $75
+ shipping, so a worthwhile saving. The bushings are silver soldered in
place using a serious torch. It was a fair amount of work to clean up the
arm enough and to get the bushings to line up so that the fulcrum could be
screwed in, the soldering was a quick affair. If someone is interested in
more detail, let me know.
I installed new fulcrums and bought polyurethane inner bushings from
Faspec. These bushings were a joy to install, and since they don't have a
metal sleeve inside, they will never rust to the bolts!!
I decided to use Neverseize, a copper paste, as a lubricant between
bushings and bolts because I feel that it stays around longer than regular
grease. I have nylon offset trunnion bushings on the car and these were
pretty much dry when I took them out (I had greased them liberally).
I also made sure to use plenty of Neverseize between the kingpin and the
fulcrum and the little...uhh...pin thingy. I had done this 4 years ago
(also on the inner bushing bolts) and everything looked as new and came
apart easily.
I had recently installed 1" lower 340# springs from Moss w/o any other
changes. Since my swaybar mount ripped off a while ago, I was able to
test the spring change by itself and was extremely impressed. The change
to these springs was a much better move than the installation of the 3/4"
swaybar that I used to run. Adding the swaybar made the car lean less but
induced understeer as expected. Installing the springs really improved
front end feel under all conditions (braking, swerving, they even
improved straight line stability). The surprise was that I got a very
predictable handling (I have a Panhard bar) with a tendency to oversteer
in constant radius curves and in 90 degree turns. This must be due to
front outer tire having more grip because it doesn't tuck under as much.
I don't know why this didn't happen with the swaybar, maybe it was to
stiff or the 1" lowering helped a lot.
My original idea was to build the hardware needed for a tube shock
conversion myself and find shocks of the right length at a parts place.
However, I found that Winner's Circle sells the kit w/o shocks for $85
which seemed very reasonable since I don't have a welder, bandsaw, etc.
I also REALLY wanted high quality shocks, adjustable if possible. I am
usually not satisfied with a modification unless I have explored the whole
spectrum of adjustment, e.g. when I installed a 3/4" swaybar with PU
bushings, it was too stiff and I backed off to softer bushings. This way
I feel good about knowing that the swaybar is just right (?) now.
So I went for the full kit with Carerra adjustable shocks ($308).
The kit is of very high quality and finish and fits very well subject to
production tolerances of these cars. The shocks have three stiffness
settings and have to be at least partially removed to adjust them. They
come set to the middle setting at 50/50 compression/rebound.
The result:
The feel of the car was transformed as hoped. A number of aspects of
the car's handling that I used to think were due to the design of the car
were dramatically improved. Straight line stability, braking, turn-in
(more testing needed :-). Of course a lot of this is probably due to
eliminating front end play. I can't tell any negative effects of the PU
bushings. With the stiffer springs and the bushings, I am sure the car is
a little harsher than stock, but since a stock Sprite has a fairly bouncy
ride as well, I don't feel that I am loosing much.
The shocks work well with my 1" lower 340# springs, but are not extremely
stiff. I will try out the hard setting soon.
How the car feels at the limit of adhesion is very important to me and I
am very pleased at this stage. Oversteer comes on gradually and
predictably and is much easier to catch than before.
The two best modifications to this end I have made were the installation
of the front springs and the Panhard bar (shorty bar from Mini Mania).
I still need rear shocks, but because there really isn't any added
hardware required (I hope) if the shock is mounted to the limit strap
mount at the top and the original shock bracket at the bottom, I want to
just measure the required length and find shocks from a listing at my
corner parts store. I will go with KYBs if I can find some.
Have a spritely day,
Ulix __/__,__
.......................................................... (_o____o_)....
'67 Sprite
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