Spring Rate Data

[jwernerny]

Originally Posted by shoestring

How about a spreadsheet for these? I love a spreadsheet.

This should work. Change the rear corner weight as appropriate, and specify the spring length and lb/in. Everything is in reference to the first one, which should be a Nivomat.

Mk I Spring Rate Calculator

[redblockpowered]

Some navel-gazing about stock rates here: http://forums.turbobricks.com/showth...85#post6064885

[mikep]

https://www.f1technical.net/forum/viewtopic.php?t=6371

[sloopy]

I was able to get some spring data from our friends at Lesjofors and they gave me permission to publish it :o)


Lesjofors {part number}
{description}
---
L: {length}
OD: {outer diameter}
WD: {wire diameter}
R: {spring rate}


################


Lesjofors 4095801
240 front
---
L: 452 mm
OD: 167 mm
WD: 13.5 mm
R: 15.3 N/mm (87.4 lbf/in)


Lesjofors 4095802
240 diesel front
---
L: 485 mm
OD: 166 mm
WD: 13.5 mm
R: 17.5 N/mm (100 lbf/in)


Lesjofors 4295801
240 sedan rear
---
L: 422 mm
OD: 127 mm
WD: 12 mm
R: 17.2 N/mm (98.3 lbf/in)


Lesjofors 4295803
240 wagon rear
---
L: 407 mm
OD: 134 mm
WD: 13 mm
R: 21.1 N/mm (121 lbf/in)


Lesjofors 4295816
240 ambulance rear
---
L: 410 mm
OD: 132 mm
WD: 14 mm
R: 30.0 N/mm (171 lbf/in)


Lesjofors 4595804
240 sedan sport kit (35 mm lower)
---
R front: 29 N/mm (166 lbf/in)
R rear: 26-35 N/mm (147-200 lbf/in)


Lesjofors 4595805
240 wagon sport kit (40 mm lower)
---
R front: 29 N/mm (166 lbf/in)
R rear:23-33 N/mm (131-188 lbf/in)


The sport kits have progressive rate in the rear. I also verified that the sport kit's rear rates are lower for the wagon.

[redblockpowered]

Who did you contact at Lesjofors for spring rates? That's very interesting. I wonder what they're willing to tell me for 740/940 springs.

[sloopy]

I talked to Jim at the Pennsylvania office. I can PM you his number.

[culberro]

Originally Posted by aharres

I was able to get some spring data from our friends at Lesjofors and they gave me permission to publish it :o)

Nice!!!

Any chance you can get the 240 diesel spring rate for the front? I had a pair that were a slight lift over stock and a go of bit stiffer.

[sloopy]

Yeah I'll give him a call on Monday.

Originally Posted by culberro

Nice!!!

Any chance you can get the 240 diesel spring rate for the front? I had a pair that were a slight lift over stock and a go of bit stiffer.

[sloopy]

I updated the table with data for the 240 diesel front spring.

[redblockpowered]

Jim says no rates for 740/940. They're kept by the applications engineers in Sweden. Now, they do publish wire diameters, along with diameter and length, and maybe they're made from the same material as the 240 springs...

[mikep]

The material used has almost no variation within the iron alloy family. But when measuring the spring, knowing the coating is important. Powdercoating can add a mm to the wire thickness, most paints 0.5ish mm.

[petercz]

Originally Posted by jwernerny

From an old post I wrote in 2008 (http://forums.turbobricks.com/showpo...0&postcount=26

IPD Nivomat Delete Rear Springs:

92.5 lbs/in. Free Length: 20". Compressed Length ~8" (1100 lb load on each spring)

Can anyone confirm, that they are really that soft? I read somewhere, there were two versions (old and actual).