This is a set of performance springs and steel/titanium retainers that we use in our race 2ZZ’s in our Lotus 211 supercharged race cars that are around 270bhp. Seat Pressure: approx. 70lbs @ 38.50mm installed height. Spring Coil Bind: 25.5mm. Max net lift 13mm. Please note which retainers you would prefer with your set of springs.