Characterization of the OE Suspension Springs
Thread Starter
Joined: Feb 2001
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From: Redondo Beach
Interesting, thanks! For some reason I never considered that those foam bits might be "active" components under moderate compression. That certainly throws (another) wrench in my suspension spreadsheet...
Joined: May 2004
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From: Tucson
Originally Posted by INTJ,Oct 5 2010, 06:53 PM
The bump stop in the s2000 is definitely part of the spring rate. It is a convoluted foam that has a progressive spring rate that is active in most high rotation turns.
I was really surprised myself went I worked on my AP2. It is similar to VW with a continuously engaged bumpstop. The density is less than celasto (Koni) but is is really long. With the weight of the car down it is in almost in contact with the shock.
I was really surprised myself went I worked on my AP2. It is similar to VW with a continuously engaged bumpstop. The density is less than celasto (Koni) but is is really long. With the weight of the car down it is in almost in contact with the shock.
Joined: Jul 2005
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From: Huntsville, Al
Read the paper, fantastic!
I just wish I had found this post yesterday before I installed a set on one of my cars. I have gotten several sets of shocks and springs and not knowing which was originally front and back, I have been checking the spring rate and then trying to set the car up as close as possible to the commonly posted rates (based on how the springs measured), which according to this post are all dramatically off!!
I just wish I had found this post yesterday before I installed a set on one of my cars. I have gotten several sets of shocks and springs and not knowing which was originally front and back, I have been checking the spring rate and then trying to set the car up as close as possible to the commonly posted rates (based on how the springs measured), which according to this post are all dramatically off!!
Good info.
Thread Starter
Joined: Feb 2001
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From: Redondo Beach
jeallen, yes, direct measurements can be deceptive since it's difficult to account for the inactive coils. Thus, one goal of this paper was to provide parameterized models of each OE spring and swaybar, along with the appropriate equations to use.
Have you measured the bump stop foam?
Have you measured the bump stop foam?
Thread Starter
Joined: Feb 2001
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From: Redondo Beach
Spring rates of aftermarket springs are usually stated directly by the manufacturer. Since Honda didn't ever really do so (except in the AAMA data sheet, reference [5] in the paper), the goal of this project was to add some clarity to the various OE spring rates, which should help folks calculate how much stiffer/softer their mods will be.
Thread Starter
Joined: Feb 2001
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From: Redondo Beach
Bump. After a review of my calculations, made some *very* slight revisions which resulted in spring rates that match (even) better with Honda's published data. The largest magnitude of change was to the '08 rears (is 294, was 290) and the CR rears (is 343, was 339). All other changes were within a pound or two. Swaybars unchanged.
Revised summary table (also updated in previous posts):
Link to updated paper: click here. (Only p.5 is changed; image of p.5 in 1st post has been updated.)
Revised summary table (also updated in previous posts):
Code:
| Front Rear | Front Rear Model Year | Spring Spring | Sway Bar Sway Bar --------------+------------------+-------------------- 2000-2001 | 219 291 | 393 427 2002-2003 | 246 309 | 300 396 2004-2005 | 262 278 | 300 311 2006-2007 | 262 269 | 300 311 2008-2009 | 280 294 | 354 311 2008-2009 CR | 384 343 | 392 362 Note 1: All figures are in lb/in. Divide by 56 to get kg/mm. Note 2: Edited 17Nov2010 with slight updates to spring rates per rev1 of paper.