To complement our other link and arm offerings, we now round out the set with rear adjustable upper control arms (RUCA) for the SC300/400, Gen1 GS300, and MKIV Supra.  We have built these arms to handle drift and track abuse with the option of street friendly lifetime poly bushings or track focused spherical bearings for the inner mounts. Along with a high-misalignment outer spherical ball joint to handle the extreme conditions of drift and track use.  The setup is light, easy to adjust without an alignment rack and allows a perfect balanced offset for wheel/tire fitment and/or camber curve modification.

Features:

• Steel plate gusseted construction for max strength, and fully TIG welded.
• Setup for mild rear camber offset for traction (road race) or positive camber for more contact patch under squat (drag/drift).  At a 2" drop, 5 degrees of total adjustment range between +2.5 and -2.5 over non-adjustable stock arm.
• In conjunction with our Adjustable LCA and toe links these arms sweep between +4 and -8 degrees of camber. If going positive camber that we would include a grade 8 jam nut for the best thread support.
• 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.

Adjustment

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. Lower links offer the infinite adjustment for fine tuning and are a better place to manipulate camber and toe changes for a stable geometry.  Alignments are always iterative, meaning as adjustments are made to one link, the other will need small adjustments as well.  By fixing the rear upper to a finite offset in graduations of 1/16" we are simplifying to overall alignment process.

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.

Options

We offer these uppers in two options. 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. 

Street Spec (SuperPro Poly Inner Mounts): The best for long life and low maintenance. SuperPro bushings are made from a proprietary polyurethane material that features internal knurling to retain the grease. Their material is unlike any other Polyurethane on the market, and is guaranteed to not egg out, deform or migrate. This is the best Polyurethane we could find and we have looked all over the world.

Track Spec (Spherical Bearing Inner 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 product 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 judgement 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.