May Spin

Which do you prefer and why?

BlackHawk T/A

iTrader: (3)

I can tell you how this thread will turn out already.

Sam will chime in and explain why its hard to properly damp a progressive spring

YellowToy/A

iTrader: (1)

But there is not many springs that are Linear. I would like to know which springs for our cars are linear.

2000Z28M6

iTrader: (13)

IMO it be better to just have trackbird or mitch explain it.

chupr0kabra

iTrader: (10)

I have Hotchkis, which are progressive. I like them because I don't sacrifice a comfortable ride when they are properly damped. I had KYB GasAJust shocks and the ride was OK, but floaty. Now I have Koni SA's (which, coincidentally, I purchased from Sam on his recommendation of this combo) and the ride is firmer and much more controlled.


-Mike

Foxxtron

iTrader: (1)

The fronts on these are: http://www.lgmotorsports.com/catalog...oducts_id=1448

At one point, there were some that were OE replacement as well that were linear that were made by the same company that LG uses, Hyperco, but don't know where they're available now, that is if they are still available.

Sam Strano

iTrader: (41)

Maybe Monday.... I'm too tired today.

And FWIW, stock springs are linear. Progressive springs can be damped, but never exactly right for all conditions. By definition a progressive springs gets stiffer the more it's compressed. Some are easier to deal with than others. But the nature of them is yet another reasons that high-quality adjustable shocks are useful. Better left up to you if you want to be overdamped at soft spring rates, underdamped @ high spring rates, or set the shock up for the middle. You don't have those choices with a shock you can't adjust. When I do Revalves for such springs (and I do it a lot). I honestly run a pretty aggressive valving to insure I don't have an underdamping issue. Rather be high than low and lack control.. I can do that with HD's.

If the thread is still alive later, maybe I'll add more.

May Spin

It would seem that all rear lowering springs are progressive other than one, suspension techniques. Even GM's 1LE rear springs are progressive. I would imagine this is done for comfort, as live rears aren't that comfy to begin with, let alone with the higher rates needed for lowering spring.

For comfort SLP Level one fronts look nice (223-448) compared to the 292ib linear stockers, however there's not much of a drop at .75". Eibach prokit rears (80-137) seem very forgiving compared to the stock linear springs at 114lb.

Does Ground Control offer any progressive springs for their kits?

Scott.

Sam Strano

iTrader: (41)

You are working under the assumption that linear must equal firmer. That's not the case. Add to that the fact that there are different ways to wind "progressive" springs and even if you had two spring with the same starting and ending rate, they could well be VERY, VERY different in their working rates due to when they "change" rates.

Which is one of the issues with these springs. You can't tell where they are in rate at any given time because the rate is always in flux. And some springs much more than others. Some "progressive" springs are fine because the soft end just gets compressed and the really just work in the upper rates. They are more "dual rate" than progressive.

The stock springs are linear, and nobody accuses them of being too hard.

May Spin

Double post.....

May Spin

Thanks Sam, It seems you can't just compare the progressive rates on these springs to determine their characteristics.... Sure, the final rate is comparable. It's what happens before you get there seems impossible to determine. Mike mentioned a "comfortable" ride with Hotchkis as have others on this board. Now on paper I've always liked the rates. Would this mean a more usable initial (starting rate) than others?

Sam Strano

iTrader: (41)

No, the starting rate is pretty much gone the minute you put the car on the ground. It means a more proper "working" rate.

Only final rates are comparable. But some progressive springs get to their final rate much sooner than others. Some only get there if you crush the suspension..... All is not equal where springs are concerned.

May Spin

Ok... So which springs (other than OEM) give the most comfortable ride during their "working" rate? Lets asume Koni's will dampen them, and your bar combo will be used for added roll resistance.

Sam Strano

iTrader: (41)

Ugh... that's not exactly cut and dried.

Hotchkis work really well and if I'm interpreting your statement correctly, would be likely the highest on the recommendation list. I carry them, $239/set.

However let's remember there is room for mis-understanding when e-mail is involved.

No Juice

iTrader: (11)

It says a lot about the stockers when Sam recommends them with the Koni's. I don't think I've heard one person complain about that set up.

Sam Strano

iTrader: (41)

They get a bad rap because of the way the car feels with the disgusting poor stock shocks.

Not everyone wants the stock springs. But very often the reasons given for changing (ride height aside) are reasons that are really the OEM spring's fault.

dailydriver

Which is a good reason to go with Ground Control coilover conversions (if $$, rules and conditions allow this). You have almost infinite linear choices up front and although limited to one company, a good many linear choices out back!

YellowToy/A

iTrader: (1)

I think you are correct dd. One big reason I got ground control is that they are linear. I still do not understand how a shock will damp a spring that is not linear and do it well. The shocks can only have the correct rate at one point on the progressive rate spring travel. Maybe the "working rate" change is small.

Sam Strano

iTrader: (41)

True that coil-overs are linear.

But again the magic bullet is in the working rate. Some progressive springs actually don't have much working rate change. Some are all over. And FWIW a poorly picked linear spring can indeed be worse than a decent progressive (and often are).

In short, linear isn't the end-all answer. I prefer to use linear or the least amount of progressives. However, the publised rate of progressive springs don't give you the full story on how they progress. For instance, Eibach, H&R springs are technically progressive, but the soft end of the spring is gone, not there, out of play. They really are pretty much linears.