9 replies to this topic

[gtred]

I have been told that SM Bilsteins use the same valving as off-the-shelf Bilstein HD's. Now that just doesn't make sense to me. Usually a shock can operate with-in 20% or so of it's target spring rate. The Miata went from approx 250#/in to approx 700#/in springs in the SM class. I can hardly believe that they used off-the-shelf valving to run that spring rate increase!(?)

The reason for my Q is that I am road racing a non-SM (MX-5 Mazdaspeed) in a regional class. I have much of the SM suspension, just not the SM springs/shocks. If the shocks are the same as the HD's, then I'll just keep the ones that I'm currently running and add the stiffer springs to my coilover perches. If there is a reason to do so, then I'd buy the SM shocks.

Thx for helping me sort this out.

[davew]

The SM shocks are off the shelf Bilstein units. No change in valving (right Sammy).

Dave

[Rob Burgoon]

I have been told that SM Bilsteins use the same valving as off-the-shelf Bilstein HD's. Now that just doesn't make sense to me. Usually a shock can operate with-in 20% or so of it's target spring rate. The Miata went from approx 250#/in to approx 700#/in springs in the SM class. I can hardly believe that they used off-the-shelf valving to run that spring rate increase!(?)

The reason for my Q is that I am road racing a non-SM (MX-5 Mazdaspeed) in a regional class. I have much of the SM suspension, just not the SM springs/shocks. If the shocks are the same as the HD's, then I'll just keep the ones that I'm currently running and add the stiffer springs to my coilover perches. If there is a reason to do so, then I'd buy the SM shocks.

Thx for helping me sort this out.

The SM suspension package is pretty much bouncy garbage. We drive quick in spite of it. Either revalve them for more damping or better yet get yourself some adjustable coilovers.

[Rob Burgoon]

The SM shocks are off the shelf Bilstein units. No change in valving (right Sammy).

Dave

That's a cheap shot. The last one wouldn't have been a DQ if SCCA had something better than a loose screwdriver for securing the lower mount on the dyno.

[davew]

The cheap shot was not directed at Sammy. Only Sammy and I know the true story. You gad to be there and get yelled by an irate shock guy

Dave

[Johnny D]

I have the SCCA Spec Miata Shock Spec PDF.
Should be online someplace.
Has Velocity, Bump Force, Rebound Force.
If that helps.
J~

[Eric Jones]

As a former Indycar shock guy, I can tell you that the Bilstiens are woefully under-damped for the spring rates we use. I have customers with street miata's that have Tokico's or KYB shocks that are much much better.

[Alberto]

If you don't need to run off the shelf Bilstein shocks w/ off the shelf valving, don't.

The shock itself is great since it works well and is well priced and can be revalved by someplace like Fat Cat Motorsports to fit your needs. The Bilstein is a much better shock than Tokicos, KYBs and what passes for a shock in the Jap/Chinese coilovers.

[Rob Burgoon]

If you don't need to run off the shelf Bilstein shocks w/ off the shelf valving, don't.

The shock itself is great since it works well and is well priced and can be revalved by someplace like Fat Cat Motorsports to fit your needs. The Bilstein is a much better shock than Tokicos, KYBs and what passes for a shock in the Jap/Chinese coilovers.

Shameless plug for one of my sponsors, the 949Racing XIDA coilovers are supposed to be pretty excellent. I've only used Tein flexes, and these are supposed to blow the flexes out of the water.

Mods, please delete if such pluggery relevant to the thread isn't kosher.

[gtred]

thank you for setting me straight on this!