Sorry guys, what springs?

[19COBRA93]

I did brakes before I did springs, and while I highly recommend brakes, they're not that great of a combination with the soft factory springs when coming off a 130 mph back stretch. I don't usually brake til I see Jesus, and the soft factory springs just aren't cutting it. It nose dives so bad I fully expect the rear tires to come off the ground. I mean obviously it won't, but it feels like it.

 

[JA BoostedSTANG]

he has some form of aftermarket susp setup though.

 

[o0Dan0o]

The number of coils in a given space changes rate even if you don't change wire diameter, or coil diameter of a spring. Why? Well I'll let an engineer attempt to explain that...

Not an engineer, but a physicist.

Let's say you take two identical springs, the same hight, the same coil diameter and the same number of coils (and the same material), they should have identical spring rates (in a perfect world, in a real world nearly identical). Now lets set you cut one of those springs, cutting off the first (or last) few coils. now push each spring down 1 inch. With the uncut spring you're pushing on more coils, so each coil has to compress less to get your total travel of one inch. With the cut coil, you're pushing on fewer coils, so each coil has to compress more to get the same inch of travel. The added compression of each coil increases the spring rate.

The same idea holds for more or less densely packed coils. Two springs that have the same height, but one has fewer coils, all other variables are equal. The one with fewer coils has to compress each coil more for an identical amount of travel, thus a higher spring rate.

Coil diameter (diameter of the spring) also plays a key role, but that relates to torsional stiffness I believe.
Dan

 

[danbev07]

Let's say you take two identical springs, the same hight, the same coil diameter and the same number of coils (and the same material), they should have identical spring rates (in a perfect world, in a real world nearly identical). Now lets set you cut one of those springs, cutting off the first (or last) few coils. now push each spring down 1 inch. With the uncut spring you're pushing on more coils, so each coil has to compress less to get your total travel of one inch. With the cut coil, you're pushing on fewer coils, so each coil has to compress more to get the same inch of travel. The added compression of each coil increases the spring rate.

EDITPerhaps I was over-analyzing, thanks Dan lol)

The way Eibach seems to make their springs non-linear is by using coil bind, based on how i perceive their design. The closer-packed coils on the spring will bind faster than the ones that are further appart, and once those closer-packed coils start binding you begin to lose your linear spring rate since metal meets metal within the spring.

 

[danbev07]

anyone running coils?

 

[o0Dan0o]

Do the math.

1/k(tot) = 1/k(1) + 1/k(2)

For ease lets assume you cut the spring perfectly in half, thus k(1) = k(2), thus k(tot), or in this case the original spring constant, is 1/2 that of either half spring.
Dan

FYI, this comes from Hooke's Law

P.S. cool vid!

 

[Xporter]

So what's a good lowering spring strictly for street use/DD? I just want to lessen the gap between the fender and tire. I'm not looking for Cadillac ride just the best riding lowering spring for the street. I was leaning towards FRPP K or Steeda.

 

[AJ]

I personally like the FRPP K's but the steeda ride very nice aswell

 

[Sam Strano]

I really prefer a particular version (there are two) of the Steeda Sports, then the Ultralites, then a few other springs, then the "K" springs and Pro-kits.