I will be experimenting with some stiffer springs over the next several months. Is there any advantage or disadvantage related to spring length? 1975 Titan FF outboard front spring/Spax shock unit with motion ratio of 2:1. Currently with 6" front springs and 1/9/16" of thread showing above the spring perch so I could use a 7" spring. I suppose that the 6" is lighter??
Thanks in advance, Joe Riley
It does not matter how long your spring is, the lenght does not determin the poundage of the spring, this done by, heat treating, materials, and diameter of steel used, and any good race shop will be able to tell you what weight your springs are and able to advise as to what you may need, you can always ask some one in a similar car, what his set up is, and you can use as a base, it may not be the correct one for you as everyone has a different style of driving, but it will give you a start. This of course will take years, as I am still chasing set up, and just when I think I have it right, I come up with another idea! but thats racing!
The only thing I've been able to come up with on this is weight (and do they fit on your shocks). A shorter spring can use a lot less material to get the rate than a longer spring, whcih would normally have more coils and larger diameter wire. That's probably why really soft springs are usually longer than stiffer springs. I'm trying to standardise on 6" springs for convenience.
There is no techincal gain from using a longer spring of the same lb/in rate. I would make sure of the clearance required to remove the spring from the shock before using a longer spring, some spring keepers require about an inch of free space to remove. Some times going shorter will save weight, but you must be carefully of coil bind.