[Jim Kaekel]

Like anything else, I think there are several things that affect the life of the coil spring. Car weight, spring rate and diameter, length of suspension travel, wheelies, etc. I've had to replace mine about every five years or so, but that's on a nose-heavy Olds 4-4-2. I know the lower the nose is, the better the car works. But, of course a little goes a long ways and it's no good to have the worry of tearing your headers up either. My .02.