The 2.25" adapter allows you to match a 2.25" ID spring up to the bottom of the factory or Tarett rear upper mounts on a 986 or 987.
This transfers all the spring load to the bottom of the mount instead of putting it on the weak rubber bushing of the stock mount, or the monoball of the monoball mounts.
On a Cayman, this 2.25" adapter allows you to use any rate 60mm (2.36") rear spring with your PSS9/10 kit. The PSS9/10 kits come supplied with a progressive tapered spring.
The bottom is 60mm, but the top is larger, making it impossible to replace with a different spring.
This adapter sits against the bottom of the upper strut mount, and allows the use of any off the shelf 60mm straight springs.
The PSS9/10 front springs are 60mm straight springs, allowing them to be replaced with no mods required.
We recommend re-valving the struts for optimum performance when changing spring rates to over 550 lbs.
2 required per car.