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The answer?<p>They don't know how to set up a stock active suspension!<p>Now before JRL jumps all over me, I know that he brought this up originally and this has been discussed before. However, I thought that it would be an interesting read for those of you who woe your 4C.<p>From the August 2006 Edition of "Excellence" (all Porsche Mag), taken from their article on the new, 997 based GT3:<p><i>Regular Excellence readers will know that we're not big fans of PASM (Porsche Active Suspension Management) as used on the first 997's - although the latest cars seem to have gone a long way toward changing our opinions. Even so, PASM in the 997 Carrera is far too stiff for road use in its Sport mode <b>causing the rear end to skip out on bumpy corners</b>. </i><p>I added the bold. However, Porsche engineers seem to be able to admit and learn from their mistakes within one model year:<p><i>To our surprise, the engineers behind the GT3 seem to agree with our conclusions - so long as the discussion is limited to buyers looking for ultimate performance. When they formulated the new 997-based GT3, they took PASM's basic "active damping" concept and then started with a clean sheet........Where the Carrera-series 911 use spring rates in the low 30-Nm range up front and in the mi-60 Nm range at the rear.....the new GT3 has 45-Nm springs in front and 105 Nm coils at the rear.</i><p><i>Perfectly matched to the active Bilstein dampers, the springs yeild a ride that's firm but compliant in normal, "Comfort" mode. This 997 is able to take the sharp edge off bumps with a level of competence manufacturers of softer -sprung cars seem unable to match.</i><p><i>Weissach engineers use the 997 GT3's springs for springing and its dampers for damping. While many manufacturers and tuners set dampers too firm in compression and get a "double-springing" effect that yeilds a jarring ride, Porsche has managed to avoid this problem in both the normal and the Sport modes of its GT3 PASM suspension. On normal roads, Sport firms up the GT3's suspension noticeably - but not to the extent it does in the Carrera models. Instead, reasonable suspension compliance is still there at both ends of this 911, and it's simply a matter of how much extra stiffness you really want.</i><p>Very, very interesting. Seems like it proves out a couple of facts that we have all been wondering about for a while.<p>1) The stock R's are undersprung for the 4C.<br>2) Putting stiffer lowering springs on the car will make the ride much more fluid.<br>3) Putting stiffer lowering springs on the car will make comfort stiffer, but also make advanced less harsh.<p>I believe that many of you who have installed lowering springs have noted the same effects.<p>Now why can't Volvo engineers admit that they undersprung the R from the get go? Wouldn't have helped my '04, but it might have helped the rest of you. <p>And cheer up, Jim, there's hope for your purchase of a PASM equipped Cayman S yet!<br>
 

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Re: What do Porsche Engineers and Volvo Engineers have in Common? (needsdecaf)

I copied the first half of that nearly a year ago. I DIDN'T read the 2nd part.<p><I>To our surprise, the engineers behind the GT3 seem to agree with our conclusions - so long as the discussion is limited to buyers looking for ultimate performance. When they formulated the new 997-based GT3, they took PASM's basic "active damping" concept and then started with a clean sheet........Where the Carrera-series 911 use spring rates in the low 30-Nm range up front and in the mi-60 Nm range at the rear.....the new GT3 has 45-Nm springs in front and 105 Nm coils at the rear.</I><p>However, wouldn't you expect that from Porsche, address the problem, find the reason and give it a cure? Unlike Volvo, who continues with the same basically unchanged system for three years trying to fix it with SOFTWARE when HARDWARE is the problem.<br>You also also have to understand that Porsches have a MUCH superior suspension to start with which gives them a lot more to work with
 

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Discussion Starter · #3 ·
Re: What do Porsche Engineers and Volvo Engineers have in Common? (JRL)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>JRL</b> »</i></TD></TR><TR><TD CLASS="quote"><br>You also also have to understand that Porsches have a MUCH superior suspension to start with which gives them a lot more to work with</TD></TR></TABLE><p>Belive me, having driven only a handful of porsches, it's noticable. <p>Having driven a bunch of BMW's it's just as noticable too.
 

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Re: What do Porsche Engineers and Volvo Engineers have in Common? (needsdecaf)

Wow, great find! <IMG NAME="icon" SRC="http://********************/smile/emthup.gif" BORDER="0"> <p>My one question is- How long was the original PASM system put in the 997 before it was redesigned? Did Porsche go back to all original 997 owners and re-work their suspensions? I doubt it.<p>
 

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Re: What do Porsche Engineers and Volvo Engineers have in Common? (needsdecaf)

Perhaps Volvo should have named our system "SPASM" instead of 4C. <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/eek.gif" BORDER="0">
 

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Discussion Starter · #6 ·
Re: What do Porsche Engineers and Volvo Engineers have in Common? (Wayne T5)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>Wayne T5</b> »</i></TD></TR><TR><TD CLASS="quote">Wow, great find! <IMG NAME="icon" SRC="http://********************/smile/emthup.gif" BORDER="0"> <p>My one question is- How long was the original PASM system put in the 997 before it was redesigned? Did Porsche go back to all original 997 owners and re-work their suspensions? I doubt it.<p></TD></TR></TABLE><p>I doubt it too. <p>But how long has the 997 been out? I think it's the second MY now, but it still may be the first. And from the tone of the article, it seems as if Porsche started addressing it later in the same MY when they say that the newer 997's are better than the earlier ones.
 

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Re: What do Porsche Engineers and Volvo Engineers have in Common? (JRL)

I couldn't agree more with your position here.<p>It is not the fact there is a problem, but what the vendor does about it that makes all the difference in the world, be it Porsche or Kia. Too oftern I think some are perceived as being Volvo bashers, (even though they voted with their wallets), when the real issue is problem resolution, not the problem itself.<p>I have driven a 997 and I can say it pretty much does what 4C was supposed to do. <p>I own a 996 with 030 ROW suspension, a non active system, and I can tell you it is firm but very much controlled.
 

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Re: What do Porsche Engineers and Volvo Engineers have in Common? (needsdecaf)

yadiyadiyadi<p>don't forget that THE original SUM-sw advanced was written to be driven on perfect tracks or streets!!!! THAT's even what VOLVO said themselve since day 1. Don't blame Volvo they rewrote the sum-sw for the ones with fillings <IMG NAME="icon" SRC="http://www.vwvortex.com/vwbb/rolleyes.gif" BORDER="0">
 

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Re: What do Porsche Engineers and Volvo Engineers have in Common? (rogersampson)

Does anyone know what the spring rate on our cars are (measured in newton meters?) compared to the new "stiffer" 2007 S60 springs and the various aftermarket parts?
 
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