[Yetiman]

I was about to post the same calculater Richard posted.

You got H&R's standard answer.

I went from H&R sport springs to race springs on a VW Corrado I own, and before i ordered them i called to find out the rates of the race springs (I had already calculated that the sport fronts were 275#) and recieved the same kind on brick wall answers.

All they would say is that the race spring was 30% stiffer.
After explaining that if they couldn't give me a solid answer I would be buying from a different manufacturer from now on and going in circles they finally told me they were 400# which is exactly what i was looking for.

I said "there, now wasn't that easy ? could have saved us both 20 minutes !"
The new springs calculated at 420#, and measured the same in a spring guage.