Dan White of Suplex has developed some new 4 leaf asymmetric springs which are of very good (UK-made) quality and designed reduce axle tramp. I have put them on my 2014 Plus 4 (the one with the 250 bhp turbo engine) to help control spring wind-up (along with anti-tramp bars). Even before the engine change the original springs on this 2014 car were useless -- sagging on one side even with no-one in the driving seat and someone in the passenger seat. I have been told the batch I got were made in Sri Lanka! I'm not sure if that's true. Anyway, I've only done about 1k miles on the new springs but I'm very impressed so far. Hope this helps.
