SPF Spring Rates?

[Zoom This]

I'm about to give up on tracking down the spring rates for my stock springs on #1735. H&R cannot give me the spring rate, even with the part number in hand, citing that it is proprietary info to Superformance. Can anyone out there tell me what rates I have on my car?? Thanks.

[Mike Simard]

Yours are probably 375 lb per in. springs.
BTW, H&R does suck, I tried calling with the same question and they were unhelpful and somewhat rude.

[Richard Hudgins]

Zoom this,

Measure the wire diameter of your spring, overall diameter of the spring and count the number of coils.

Then go to Coil spring rate And put in the numbers.

Your spring rate will appear in the right hand window as if by magic.

[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.

[Zoom This]

Well, there you have it. Thank you Richard.

SPF spring rates on my SPF #1735 are 375 lbs., front and rear. .45 wire diameter, 3.25 coil diameter, 7 active springs.