Picked up a set of rebuilt Motons in March and have finally collected all the bits to have the installed this week on my 996 C2 while I'm out of town on vacation. I got word from my tech yesterday the inner diameter of all 4 springs is approx 2 mm too small to fit the Moton spring perches the ID of the springs is 58-59 mm while the OD of the perches are 60mm. The perches will not fit within the spring diameter. See attached photos. The springs in question are 800/1000 6" that were provided with the coilovers but not originally mounted to them. So...., not knowing a whole lot about this, is there a trick to get them to fit or do I need to purchase new springs (or perches)? If I need to purchase new springs, can anyone recommend a source? Better yet, if someone has a set they'd like to sell, me, let me know as my car is apart until I get this sorted with my tech.

Bump. I would appreciate anyone's help in getting this figured out...

It would appear the perches you have are designed for 60mm (metric) springs while you are trying to use 2.25" (57.15mm) springs.

You either need new/modified perches or 60mm springs. Do a search here for people that support Moton dampers. They should be able to tell you if you have an option in regards to perches.

Scott is correct here.

You will either need new metric springs or you will need new perches. Those spring rates sound a bit heavy anyhow so you might be happier with a different spring set up.

It's probably faster and easier to get new springs in the rates you want, plus you can sell the 2.25" ones.

Thanks to those who have explained the issue I'm having. I emailed my tech to contact ANZE Engineering (I'm currently abroad and int'l cell rates will kill me) and get the proper springs. I'll drop down to 600/800 being I'm now buying new.

I have a set of 60mm that came with my used motons that may work to get you started. 628/970 with helpers and couplers.
https://rennlist.com/forums/parts-ma...d-helpers.html