I can't believe I'm posting this twice in the same day! I've had this saved for a long time and besides bringing it to my alignment guy each time.........I don't get to share it that much. Now, twice today!



Enjoy!

 

So this is only for the 99-01 MY though right? Or will these specs work for later MY's as well? In particular, will they work for an MY05?

Thanks,

Brandon

 

i know the pic is dark but this is the GC's on yellows with about 7 threads left front and rear. damn near impossible to drive but it was fun for a few days.

 

anyone has any idea as of what the spring rates are on the Espelir ASDs and the Eibach Pro-Kits?

 

^look in the group buy section steve@evolution has them for sale the ASD's and has all the specs on the springs

 

Lowering can attribute to early failure of the shocks because lowering springs put more stress on the stock shocks. The stocks shocks were meant to ride at a certain height and compression, when lowered the shock is compressed and the pressure inside is greater (there-by putting more pressure on seals etc..). It really just depends on the shock and spring combo, for instance a harder spring lowered the same amount will put less stress on the shock when it compressed over bumps. After market shocks (like Koni yellows) are made specifically for lower ride height, and so have their optimal internal pressure and settings corresponding to the drop in height. Lastly I would think that it would be the front shocks that would blow first (this is complete speculation as I am not sure about the effects of lowering on shocks with remote reservoirs) because the rear shocks with external reservoirs may be able to compensate more externally there-by releasing some stress.

If I'm wrong please correct me, but that is how it has been explained to me by a few garages (most of which were quite knowledgeable for track prepped Porsches as this was back when I had my 944) and had read in magazines/books.


btw you guys need to get different icons for yourselves, for a min I thought we had a skitzo on the board arguing with himself

 

You should be able to get these numbers with any model year. I've never heard of any particular model year having issues. As a matter of fact, the USDM AP2s are noted for having the worst (re: least aggressive) camber settings. If I were to purchase a new one now, I'd probably have the alignment checked right off the boat........but thats just me. I kinda like the Euro settings .

-Hockey

 

Thanks for responding.

Same here; If I'm wrong, I want to be corrected. Certainly if I already knew all the answers, I wouldn't be asking questions.

Here's what I don't understand ...

The way I understand it, shocks work by passing fluid through orifices (and valves), and the fluid simply moves from one chamber to another; This makes the pressure a function of velocity rather than position (and the valves in the shock open to regulate the pressure). IOW, shocks are velocity sensitive rather than position sensitive.

The only position related pressure in shocks (that I'm aware of) is in gas pressurized shocks, and in the case of gas pressure, the design has to be able to work throughout the entire range of suspension motion without blowing out the gas seals. If that wasn't the case, then the shocks would blow the first time a bump pushed the suspension against the bump stops.

The force of a spring changes as it is compressed, but the forces inside a shock absorber do not, unless the shock is gas pressurized, and in that case the gas is an air spring, and will function throughout the entire range of travel.

As long as the design stroke and velocity of the shock is not exceeded then it sould not fail.

Now all of what I just said may be totally wrong, but if it is, I need someone to explain why, because if it is wrong, then I don't really understand how shock absorbers work (and I thought I at least understood the basics).

As far as I'm aware, all aftermarket shocks are designed to work properly and effectively over the full stroke of the target suspension. If that's not the case then I'd like to understand why.

When you put a good set of shocks on a car you can adjust the ride height to whatever you like, and the shocks work at every setting. Has anyone ever seen an AFTERMARKET shock that had to be replaced or re-engineered every time the cars ride height was changed? I know I haven't. Do shock companies specify the design ride height? No, as far as I know, they do not (because it is not relevant). They provide curves that show the damping plotted against velocity (not position), because that's the way shocks work. If this isn't the case then somebody PLEASE educate me, because I really did think I knew how shocks actually worked, and I don't want to remain stuipd.

Well, under different circumstances I'd explain the function of the external reservoirs, but my understanding is based on a theory of shock absorber operation that may be totally wrong, so all I'll say is that I thought the extra fluid capacity was for cooling, not pressure relief. The rear shocks produce more heat, because they work harder to control greater sprung mass. LOL, or so I thought.

I don't know, but either I totally don't understand anything about how shock absorbers work, or this theory doesn't hold water. It would be nice if somebody who really KNOWS would comment, but honestly, I'm just thankful that someone stepped up and proposed a theory to explain the belief. Now all we need to do is figure out which "theory" is correct.

 

I think the UK specs are a good starting point for any AP1. AP2's are another matter, and with an AP2 I'd start out with the original specs and work from there.

 

I've seen spring rates quoted for the Prokit springs, but the springs are progressive and the quotes don't give any indication of the percentage of compression at which the rate was measured, so the numbers I've seen don't provide enough information. When compressed to their normal ride height they are very close to the stock spring rate (which is why the ride quality is so close to stock), but they get stiffer as they're compressed. I have never seen a curve of the rate vs. compression, and that's what you really need to see to evaluate progressive rate springs.