Discussion
So I got an S2000 track car a while back and had a back wheel or at the weekend for a caliper rebuild and noticed the springs have been cut by the previous owner (he did all the track prep). Now I know it's a common thing in America, but generally frowned upon over here. It makes me uneasy but has anyone got any real experience of this with which to reassure me/scare me s
tless?
Had a look on ebay for replacements and recognised the springs that are on there as a fairly cheap set from an unfamiliar brand. The car is stupidly low which now makes sense as to why!
I noticed the bottom coil was cable tied in place which I thought was just to prevent it become unseated when jacking but then noticed the cut...
tless?Had a look on ebay for replacements and recognised the springs that are on there as a fairly cheap set from an unfamiliar brand. The car is stupidly low which now makes sense as to why!
I noticed the bottom coil was cable tied in place which I thought was just to prevent it become unseated when jacking but then noticed the cut...
Cutting springs isn't a good idea to lower a car, and here's why:
The stiffness (rate) of a coil spring is given by the formula - Gd^4/ 8nD^3
G= modulus of rigidity of material
d= wire diameter
n= active coils
D= coil diameter
Don't work it out, but note that all that is changed by cutting the spring is 'n', so the spring will be very little stiffer for being shorter.
Grounding at worst and 'bottoming' on the suspension stops at best is likely.
To lower a car, shorter but stiffer springs are needed to prevent this, and that needs changes in the other parameters. G, unlikely, but 'd' easily done by the manufacturer. There is an an enormous range of coil springs in all sizes and lengths, all cheap, so no excuse for a cut spring bodge!
John
The stiffness (rate) of a coil spring is given by the formula - Gd^4/ 8nD^3
G= modulus of rigidity of material
d= wire diameter
n= active coils
D= coil diameter
Don't work it out, but note that all that is changed by cutting the spring is 'n', so the spring will be very little stiffer for being shorter.
Grounding at worst and 'bottoming' on the suspension stops at best is likely.
To lower a car, shorter but stiffer springs are needed to prevent this, and that needs changes in the other parameters. G, unlikely, but 'd' easily done by the manufacturer. There is an an enormous range of coil springs in all sizes and lengths, all cheap, so no excuse for a cut spring bodge!
John
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