Thanks for the correction
Nissan Competition
* 55020-H1023 SPRING/REAR (140 LBS/IN)
Datsun Competition Suspension Manual
Quote:
The original rear springs are replaced with modified Datsun 1200 Competition units, Part Number 55020-H1024. The competition spring assembly contains three leaves held together by a single bolt.
Before installation, both of the competition springs are modified by removing the bolt and discarding the bottom (short) leaf. Then simply bolt thetwo remaining spring leaves back together. This modification will result in a spring rate reduction of approximately 25% from the unaltered competition spring assembly, but an increas of approximately 10% over the stock 1200 assembly.
Stock rate is 109 lbs/in. Add 10% = 120 lbs/in
Many smooth tarmac racers on this site recommend much stiffer springs, to match upgraded stiffer front springs