Review: HKS Hipermax IV SP for 370Z

MaysEffect

Sorry to be a source of annoyance again. But the helper springs are not for controlling or helping compression during normal conditions, as arse backwards as that sounds. They're fully compressed and only aid in seating the main spring under full droop conditions. most helper springs if not all are less than 2kg in rate, usually less than 1kg (10-55ib/in)

The rate of those main springs are actually properly matched for the weight of the car, the caveat is the overall length. You'd only really need to use the helpers if the spring itself is shorter than the perch to perch distance or to reduce adding additional preload during droop.

Tender springs need to be used when trying to add dual rate functions and can range from 1kg-20kg.




Excellent review OP.