Toyota Supra A90 / A91 Penske Racing Dampers

     An Immediate realization was that there was not an inverted option available, short of the Toyota GR Supra GT4. 15 years ago, we learned the importance of an inverted setup at AST USA, as we were responsible for building the test rig to apply a minimal amount of side load on the strut during dyno testing. The results of an inverted damper were surprising and led us to only build inverted damper kits for any serious racer. At LGR, we fixtured and welded all of the spec iron strut casings, in addition to many porsche, BMW and Subaru strut casings for AST USA, which is now led by Chris Hagen, affectionately known as Inertia Lab. 

     The inverted strut design maximizes strength and durability. Because of the inverted style, the inner and outer tubes take all of the side load commonly encountered with strut applications. Typical struts use a large 22mm shaft that is responsible for side load distribution and sealing. Our inverted design takes the side load and distributes between the inner and outer body, while sealing is done with our standard 5/8" shaft inside. This design maximizes strength, while reducing friction because of it's small shaft. Plus you don't have to replace seals constantly from side load effects. Penske Shocks race proven struts have endured and won the 24hrs.

Given a clean slate design, we decided to add a rideheight-independent-of-spring-preload aspect to this kit. In many cases, a coil over kit will require some level of spring preload on the ride height adjuster to achieve a desired ride height. This is acceptable, to an extent. We have an internal rule that we try to minimize preload to no more than 3 turns. Any more preload and the force to required to move the shock position changes. This is less than ideal, and why we always try to achieve zero preload. The front has a ride height adjuster to the knuckle, and the rear we took inspiration from the GT4 car, and have 1mm shims, to achieve a 25-30mm window of ride height adjustment, independent of spring preload.

Kit includes LGR rear upper shock mounts and shims, and is shipped with your choice of springs and pictured camber plate, as it needs to be installed prior to final assembly of the reservoir hose. If you need us to help with spring choice, we are happy to do so, just send us a message.