The GKTECH S13 240sx/Silvia SR20 engine torque dampners do as the name suggests, they dampen the movement of the engine under load.
Particularly useful in a drift car where the car is off and on the throttle although all forms of motorsport will see an improvement in the feel of the car but without the drastic increase in vibrations that using solid engine mounts will see.
NOTE: Will only fit with SR20's
NOTE #2: May not work with high mount turbo setups.