The front suspension on the 240sx is a McPherson strut assembly. It is composed of a shock leading from the chassis down to a spindle. The spindle is then attached to the lower control arm (LCA) and the tie rods. The LCA is attached to the Tension Compression (T/C) rods.
Lower Control ArmEdit
These are replacements for stock soft rubber bushings. They are usually polyurethane and are stiffer than stock units.
These are complete replacements with pillow ball end links. These are very important because they allow the adjustability of LCA angle. When the car is lowered the LCA moves more horizontal in comparison to the ground increasing the possibility of bump steer. With aftermarket LCA's you can adjust this and return the angle of the LCA back to stock. hehe
Same as replacing LCA bushings. Tightens up the car, but doesn’t allow any more adjustment.
This should be one of your first modifications to your car. The McPherson strut assembly is extremely hard on this part of the suspension. If you haven’t replaced it, it is worn out, end of story. When braking, the car's weight shifts forward onto this bushing, causing it to be the first to wear out or fail. Aftermarket replacements are recommended because they fully replace the bushing with a pillow ball joint and allow caster adjustment.
It is worth replacing with stock if you are just trying to maintain the car because they do wear out and with that you will lose steering feel, but aftermarket has its advantages as usual.
Inner Tie RodsEdit
The inner tie rod can be equipped with a spacer to let you have more steering lock to lock. This is good for drifting because you can get more angle in your drift. Also on the S13 the inner tie rods are very small and tend to bend or to break. The S14/Z32 size is much bigger and a necessary upgrade for any real race car. The S14/Z32 inners thread right into the stock steering rack and align with no problems.
Outer Tie RodsEdit
The OEM outer tie rods are ball joints filled with grease. They are great for longevity, not great for performance. Aftermarket tie rods are pillow ball joints which help with steering feel. They also allow bump steer adjustment which will make the car easier to control.
The rear suspension is comprised of an excellent multi-link suspension design. It has 4 "sides," the rear upper control arm (RUCA), the forward link, the lateral (toe) link, and the rear lower control arm. This design allows for a lot different of adjustment and control over the rear suspension movement. Its all housed on a single "floating" sub frame which is bolted onto the chassis and incorporates the differential, and other suspension.
Lower Control ArmsEdit
Better than doing nothing. Essentially the same as effect as doing this for the front LCA's.
These also come with pillow ball joints. Much stiffer than any bushing you can buy. They also allow for roll center adjustment...
Toe Control ArmsEdit
Tightness up the ride. Stock units can be adjusted, but race units are much more accurate and have more range of adjustment.
Pillow ball joints once again, add more adjustability than stock.
Upper Control/Camber ArmsEdit
Once again better than doing nothing, but defiantly can be improved upon. Also adjustment with this piece is very limited stock and is necessary if you plan on lowering your car. You can slot the stock pieces to allow for more adjustment, but I don’t recommend it.
The RUCA's are the second most important piece of linkage (next to the TC rods). They (as usual) have pillow ball joints and allow for more adjustment. They take a lot of stress so its important to get quality pieces. The S13 OEM style had a full loop style that goes all the way around the shock. The S14 OEM style RUCA's only go around the rear. Aftermarket RUCA arms can be found in either style. The half round style is more than sufficiently strong for either application and allows servicing of the shock without removal of the arm.
Same as usual. Tightness up the suspension further.
Pillow ball joints and more adjust