Really silly question:

Is there some way to know - other than looking at the values and assuming that the damping is reasonable - whether rebound is being plotted up or down?

I'm used to rebound always being down and often become confused.

 

The data clearly shows "compression" as negative and "rebound" as positive values.

From an engineering perspective, rebound should be positive as it is tension force and tension is traditionally positive while compression is negative.

As far as "traditional" in shocks, I have no clue if rebound is usually shown as negative values. I did what made sense to me as an engineer. Sorry if this doesn't align with tradition. I have seen other graphs showing rebound as negative values though, so I know where you are coming from.

 

That's the piece that I was missing (having never taken a formal physics course). Thanks!

 

Oh boy, just what I needed before sending my Bilsteins to be rebuilt. Another technical thread to confuse me.

I really don't understand the specifics terms at all and can't help thinking it's not a good idea to tell Bilstein exactly what I want when I'm not sure myself. I am using Swift Spec R (MR version) springs and was planning on sending my Bilsteins in with the following on the order form:

Please revalve for these springs:
Swift Spec Rs MR: F: 157 (helper section) 358 (main rate), R: 153 (helper section) 380 (main rate)

Should that be okay? I remember reading a comment from Smike in a previous thread saying to just tell them the spring rates and let them work their magic. Hoping that's the best way to go and at least won't handle worse than stock valving.

 

Springs should be mounted with tight coils on the bottom as per 1st picture picture below ... which means writing on the springs is upside down.
2nd picture (detailshot) looks upside down.

 

Why? Helpers at the top means less unsprung weight. For this reason, unless the spring has asymmetrical ends and can't be flipped, I've always put the helpers at the top. What am I missing?

 

Instructions as per Robi for these springs. Agree with your statement in general. I can't really see how it makes much difference ... other than possibly noise from more coils that can potentially contact the spring tower. Moving helper from top to bottom sometimes supposedly cures clunking for people.

 

I got some more info from a bilstein dealer. The #@0.5in/s came out of a bilstein circle track brochure. The dealer how ever told me it is 1/10 of N@0.52m/s. I.e. 300 means 3000N@0.52m/s.

Not sure what is right or if it just depends on the line of shocks you are looking at.

 

Maybe I need to sit down and go through this thread again from the beginning, but the idea that the shocks had anything close to 368# or even 190# at a half-inch per second seems crazy, crazy high. As in: an order or magnitude too high.

 

From where came these values? I'm not doubting them; I just want to know if the sticky on spring-rates needs to be updated. The sticky claims that Swift Spec Rs are 5.5k/5.5k, which is down around 310#/310#. Your values are 6.4k/6.8k, because we ignore the helper section.

 

I believe the 5.5k/5.5k rates you are referring to are for the Swifts made for the Evo X, not the 8/9's.

 

Doh!

Normally I never stray from the X-related sub-forums. I completely forgot that this conversation was elsewhere.

Apologies. If I had mod powers in here, I'd make this embarrassing exchange disappear.

ps. thanks for being gentle; as the folks in the X-related sub-forums know, I don't deserve it

 

No worries