I recently bought some H&R RS2 springs via eBay from here:
http://stores.shop.ebay.co.uk/Tom-s-...__W0QQ_armrsZ1
Cost me EU346.50 or about £300. 29969, correct H&R code for RS2.
They turned up in a nice gunmetal finish, a little more subtle than the older lime green versions.
They are 30mm shorter than the OEM RS2 spring. Baring this in mind I imagined they would be stiffer than OEM and/or have a rising spring rate.
Forum members seemed to believe H&R’s are stiffer than OEM RS2 springs. A bit harsh for simple road use but great for track work or pairing with 18” wheels was the general view.
No one seemed to know the actual numbers and H&R were not forthcoming, so I got in touch with my old Mech Eng. Dept to get some real data.
H&R Results:
Fronts seem linear, with a near linear compressive spring rate of 24.5N/mm. Took the fronts to 150mm travel, they were not changing rate much at this point, and looked quite coil bound at the top.
Took the rears to 110mm. They were starting to bend sideways at this point, as the tops and bottoms are not flat. Did not want to bend springs out of line, so stopped test at this point.
Added trend line, linear to rears, you looking at about 40.1N/mm. These are not linear, a second order poly fits quite well, but the rate does not change that much.
The forum suggests OEM RS2 springs are rated as:
Front: Rated at 210lbs/inch (or 37N/mm)
Rear: Rated at 300lb/inch (or 52N/mm)
So, IF the OEM spring rate data is correct above, then H&R springs are softer than OEM RS2 springs! Who would have thought it eh?
http://stores.shop.ebay.co.uk/Tom-s-...__W0QQ_armrsZ1
Cost me EU346.50 or about £300. 29969, correct H&R code for RS2.
They turned up in a nice gunmetal finish, a little more subtle than the older lime green versions.
They are 30mm shorter than the OEM RS2 spring. Baring this in mind I imagined they would be stiffer than OEM and/or have a rising spring rate.
Forum members seemed to believe H&R’s are stiffer than OEM RS2 springs. A bit harsh for simple road use but great for track work or pairing with 18” wheels was the general view.
No one seemed to know the actual numbers and H&R were not forthcoming, so I got in touch with my old Mech Eng. Dept to get some real data.
H&R Results:
Fronts seem linear, with a near linear compressive spring rate of 24.5N/mm. Took the fronts to 150mm travel, they were not changing rate much at this point, and looked quite coil bound at the top.
Took the rears to 110mm. They were starting to bend sideways at this point, as the tops and bottoms are not flat. Did not want to bend springs out of line, so stopped test at this point.
Added trend line, linear to rears, you looking at about 40.1N/mm. These are not linear, a second order poly fits quite well, but the rate does not change that much.
The forum suggests OEM RS2 springs are rated as:
Front: Rated at 210lbs/inch (or 37N/mm)
Rear: Rated at 300lb/inch (or 52N/mm)
So, IF the OEM spring rate data is correct above, then H&R springs are softer than OEM RS2 springs! Who would have thought it eh?
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