At checkout put which size shaft diameter you need in the notes. The tankless kit includes everything you need to install the air cup lift system. Pre-wired 16mm LED switch (1 switch, operate front + rear at the same time).
Complete VIAIR compressor kit with 2 gallon tank. Make sure you have enough clearance around the coilovers, the air cups are 120mm in diameter, the fitting is 17mm. (110mm air cups available on request). The air cups can only be installed on linear springs, it will not fit on''shaped'' springs as shown in the figure.
In some situations shaped springs can be changed to linear springs. See picture of springs for reference. Measure the thickest part of the shaft, we strongly recommend to measure with a caliper. See picture for how to measure.Air cups are available for coilover shaft diameters. (57mm on request) Maximum outer diameter for 110mm air cups: 89mm. In most cases the air cup will take between 20 and 30mm of height. The air cup itself is 20mm thick and with most coilovers the top hat comes on top of the air cup, this will take around 10mm. If there is enough thread left on the coilovers to lower the springs, it won't be a problem. If not, you will need to install shorter springs. The lift from the air cups requires droop / rebound from the coilovers. If you don't have enough droop, the air cups can't lift the full 50mm. The damper strut simply will top out before achieving the full lift. If you're using the standard spring rates that came with your coilovers, it should be fine.
If you're using higher spring rates we recommend to use helper springs to get the full lift. Droop, also called rebound, is basically the amount of travel you have between ride height and full extension. Too much preload will decrease droop, we recommend to set a minimal preload. If you're using extreme high spring rates, higher than the original rates that came with your coilovers, the weight of the car won't compress the springs enough to create enough droop.
This problem can be solved by installing helper springs, these will create enough droop for the air cups to lift.