To complement our other link and arm offerings, the IS-F product category gets a new adjustable upper arm (FUCA) We have built these arms to handle track abuses as they were commissioned for a Nurburgring track IS-F. With lifetime poly bushing or spherical inner bearing options and high-misalignment outer spherical ball joint, these have all the necessary components to handle the extreme conditions of track use. The setup is light, easy to adjust without an alignment rack and allows a perfect balanced offset for wheel/tire fitment of camber curve modification. The IS-F has a tight arm pocket that it travels up into so we had to come up with a unique design. We leveraged our past 4 years of PROAngle testing and competition on the JZX90 platform and created a similar design for the F that is fully boxed, TIG welded and has a compound camber/caster adjustment via the outer rod end. An additional adjustment is made with optional inner SuperPro Poly bushings.
Boxed Steel plate construction for max strength.
100% Precision TIG welded.
Setup for mild front camber offset for traction (road race) or positive camber for more contact patch for straight line grip (drag/drift). Max range is -4.5 to -1.5(with grade 8 jam nut)
SuperPro Lifetime Poly bushings for inner mounts or custom Precision FK PTFE Spherical Bearings.
Outer ball joint replaced with Precision High-Misalignment PTFE Rod end and monolithic Chromoly taper stud.
Outer ball joint set with Belleville washer on the jam nut for addition security.
Never tamper with the outer ball joint assembly as it is retained with several adhesives for safety.
Our rear arms are symmetric adjusted meaning you adjust both sides by the same amount via the outer rod end thread. Though it may appear inconvenient, the upper arms should be adjusted as a fixed offset and infinite turnbuckle adjustments can create differences from side to side impacting handling and steering bias. Since the lower arms are fixed as well and the subframe is aluminum, the static offset should general asymmetric camber curve on both corners. Alignments are always iterative, meaning as adjustments are made to one link, the other will need small adjustments as well. By fixing the front upper to a finite offset in graduations of 1/16" we are simplifying to overall alignment process and also making it easy to adjust to a predetermine setting instead of a measured setting.
Primary adjustment is done with the wheel off as a static offset. Start with a deterministic number of turns on the upper rod end from fully seated. This means thread it in completely, then spin it out the same number of turns per side. The max strength of the rod end will de-rate after 10 turns outward or 0.625" of exposed thread beyond the jam nut. We strongly suggest keeping the max thread engagement possible to maximize safety. If using these arms for positive camber correction we will include a grade 8 jam nut to provide additional support. Each turn (full rotation of the rod end) will net close to .8 degrees of camber change.
We build these with several options for customization and user input. If one of our options does not meet your vehicle goals contact us about custom options. Camber goals are a starting point but given the specialized nature of wheel fitment and body work, we ask for a center point on the arm length for custom setups and we will also provide a length offset number for our standard configurations. We have complete suspension maps and can offer setup advice on adjustment and general ranges for fitment.
SuperPro Poly Inner Mounts: The best for long life and low maintenance. Lifetime poly features grooves to hold grease and a break-through material that is unlike any other Polyurethane on the market. Guaranteed to not egg out, deform or migrate, this is the best Polyurethane we could find and we have looked all over the world. An added benefit of our design is that we use factory bushing dimensions. This allows us to reuse SuperPro bushings that were previously purchased and perhaps installed in the factory UCA. At this time we have only confirmed OE SuperPro bushings and we do not suggest another brand due to fitment tolerance and potential failure due to improper fit.
Centered: The center tube of the bushing is centered and concentric, no adjustment and centered pivot.
Adjustable: The center tube is knurled and offset drilled making adjustment possible depending on how they are clocked when the mounting bolt is tightened. Knurls bite into the sheetmetal to hold the center tube in place during normal operation. These bushings can be adjusted on-vehicle by unbolting the ball joint of the upper arm, rotating the arm with the bolts loose, then tightening the bolt again to hold the center tube. The tube will rotate around 15-20 degrees per swing to adjust clock. Generally, we suggest using this as range offset for your desired settings, meaning full in or full out to reduce ambiguity.
Spherical Bearing Mounts: The most precise, free-moving motion transfer connection, these bearings are a must for higher loads and stresses from aggressive wheel fitments. The bearings can produce low-speed squeaking related to the tight interface and PTFE fabric but PTFE dry lube worked into the interface should resolve the noise.
Safety and Maintenance
Like all of our products, these are arm provided for customers to use AT YOUR OWN RISK. Proper setup, alignment, and installation should be done with reasonable and prudent judgment and any concern should be raised immediately. Arms should always be inspected within 100 miles of original install and inspection of jam nuts and mounting bolts should be verified to be fastened securely. Rod ends should be centered on their mount to minimize bias and maximize misalignment. Rod ends should only be lubricated with PTFE dry lube and never grease. Rubber boots are available however frequent internal lubrication is required again with a PTFE dry lube.