At 08:47 AM 11/23/98 -0600, you wrote:
> It's about time for me to start shopping for all of the parts to
>rebuild the suspension (and upgrade brakes) on the Garage Queen. My
>intent is to set the car up with the capabilities for fairly aggressive
>street driving and the occasional autocross.
In order to determine the status of what you already have, the first
operation is to dissassemble the assembly, clean all the crud off the
components and do a detailed inspection. Because you are running Nylon
type bushings, this will be easier for you than for most. The only front
suspension component that should require pressing is the upper A_Arm ball
joints. You will be looking primarily for the initiation of stress cracks
and the evidence of settling or partial collapse of the crossmember. It is
typical for the frame and crossmember to drift together toward the
centerline of the Tiger. You should check the distance between the
X-member mounting holes with the Factory dimensions. A reduction of 1/4"
is very normal. To restore this dimension to original specification you
will need a hydraulic jack type system. Be carefull here, you must over
extend because the structures will spring back, but you don't want to over
do it. Its easy to push too far and tougher to get it back. This jack will
be used on the frame rails and on the crossmember. Pay attention to the
quantity of shims on the upper A-Arms. If it is currently 1/16" or less
you will want to make this correction in order to have some latitude for
alignment. It will never get any better on it's own. Inspection of the
frame rails in the area of the X-member attachment is critical.
Delamination of the front portion of the frame between the mounting bolts
and the bumper attachment is becoming quite prevalent.
The X-member is likely to show cracking at the shock tower attachment
points to the spring domes, unless it has already broken and has been
repaired. It is important to "box" the arch where the upper snubber seats
to form a shear wall which reduces chances for further failures in this
system. Cracks also typically appear at the joint between the upper and
lower halfs at the point where the steering recess crosses this joint.
They usually start at the outside and propigate inward toward the 1/4" dia.
hole and beyond. Other areas are at the heat effected zones where the
spacer pads are welded to the lower shell at the A-Arm mountings, and at
the top of the weld area for the rack adapter fittings. A small amount of
cracking is easily repairable but if you observe major cracking, you may
want to consider replacing the crossmember with a modified Alpine unit. I
advise having the sub assemblies sandblasted to white metal before welding.
Any pressing or repositioning should also be done prior to the welding
operations.
The A-Arms should also be reinforced with extra welds in appropriate
areas. The spin welds attaching the bushing tubes and the upper ball joint
tubes need to be skip welded to make sure they stay put. Doesn't take much
weld to prevent them from pulling loose under aggressive loadings. The
lower arm sway bar slots will require bridging if you are going to increase
it's diameter. I use 1/4" rod to create these bridges. You didn't say if
your Nylon bushings were setup for grease fittings. I recomend this as it
reduces the typical squeeking that comes from water induced rust on the
pins. Nylon bushing always require some positive control of nut rotation.
Either safety wire or double nutting will do as long as you inspect
regularly. If you want to get real serious, you can also get Doug Jennings
Fulcrum pins and make sure you reinstall them correctly as they are Not
symetrical.
Rick at SS now has new upper and lower ball joints, with the design
taken
from the best features of previous manufacturers. They are all fit with
zirc fittings but are not copper or cad plated like the OEM Engineered
Products. As such I recommend the use of Marine grease to reduce rust
tendancies. The durability of the rubber boots is unknown at this time,
but worst case, you can replace them. The boot part numbers have been
published on this list.
If your wedges are corroded you can replace them with shortened Alpine
units, or you can have them machined from aluminum stock. Remember also
that you have an opportunity to adjust the caster with these spacers so if
you make them thicker in the rear, you will increase the maximum caster.
You will also want to examine the rear spring mounts. Most Tigers have
cracked the inner side of the front mounts at the connection to the X
frame. A simple 1/8" angle lamination will spread this load out nicely.
Also examine the Panard bar mount on the frame. If it shows cracking, it
is best to remove this bracket and apply 1/8" plate to the frame and
reinstall the bracket. I like Dan Walters Traction arm for street and
light competition operations.
Finally, do yourself a favor and find a rotissere for your cleanup
operation. Gravity sucks and you'll really know what I mean soon afer you
start this job on jack stands. Hope this is some help.
Tom
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