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KBO (Kerb Blow-Off) option in development
#21
Hysteresis is good on most of the KBO systems we've run. Compared to non-KBO, it depends upon how much force we're trying to build how quickly. You have to think in terms of ideal shock velocity operating ranges. When you're running a system like this (and I refer you to Penske's hysteresis results!) you can easily get wide pressure variations around zero velocity. Point is you want it to be consistent and choose the right compression behavior for your environment.

The high-end rally shock I measured some years ago had 'terrible' hysteresis (my first thought) but looking back I realize it was appropriate to that application. The residual force on the second half of the compression stroke stayed high (say 30-50 lb), which decelerated the suspension and caused it to extend faster, prevent jacking down and increasing suspension travel. Come out here for a vacation and I'll show you a bunch of dynos Wink

We might be putting Sennas setup on a local customer's STR car, the spring rates and weights are very similar. I've started hitting speed bumps comfortably at 20 mph even after lowering him to about 4.75" pw.
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#22
(12-26-2013, 06:52 PM)Shaikh Wrote: The high-end rally shock I measured some years ago had 'terrible' hysteresis (my first thought) but looking back I realize it was appropriate to that application. The residual force on the second half of the compression stroke stayed high (say 30-50 lb), which decelerated the suspension and caused it to extend faster, prevent jacking down and increasing suspension travel.

This part right here is VERY fascinating to me.
I always just wrote those kind of slopes off as just really bad hysteresis, but it actually does make some sense when you stop and think about the shock being pushed on the downward stroke in the rebound phase keeping the tire's contact patch more evenly loaded against the ground and it's many surface imperfections.

I'm dying to try a set of KBOs and compare them back to back to my 3040s and 1040s. Big Grin
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#23
(12-26-2013, 06:52 PM)Shaikh Wrote: Hysteresis is good on most of the KBO systems we've run. Compared to non-KBO, it depends upon how much force we're trying to build how quickly. You have to think in terms of ideal shock velocity operating ranges. When you're running a system like this (and I refer you to Penske's hysteresis results!) you can easily get wide pressure variations around zero velocity. Point is you want it to be consistent and choose the right compression behavior for your environment.

The high-end rally shock I measured some years ago had 'terrible' hysteresis (my first thought) but looking back I realize it was appropriate to that application. The residual force on the second half of the compression stroke stayed high (say 30-50 lb), which decelerated the suspension and caused it to extend faster, prevent jacking down and increasing suspension travel. Come out here for a vacation and I'll show you a bunch of dynos Wink

We might be putting Sennas setup on a local customer's STR car, the spring rates and weights are very similar. I've started hitting speed bumps comfortably at 20 mph even after lowering him to about 4.75" pw.

If I'm ever in San Jose (un-likely) I'll definitely take you up on that Smile That's actually probably my ideal vacation haha, the wife's... not so much.

I'm not terribly surprised you don't want to share the graphs in a public forum. I know a guy who just got his penskes revalved by someone pretty popular and was sworn to secrecy about the valving Tongue

I might have to have you re-valve the suspension on my Stock class Rallycross car in the future. I'm liking the things you're saying Smile.

The E46 I assume has inverted 36mm pistons on the front, can KBO be that easily adapted to 36mm pistons already?

I'm looking forward to next season Smile

PS - you can just change my User Name to Mike G.
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#24
(12-26-2013, 06:52 PM)Shaikh Wrote: I've started hitting speed bumps comfortably at 20 mph even after lowering him to about 4.75" pw.

That's great! now lets start hitting those curbs/bumps at 70mph and get some data points....
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#25
Any idea when production will start with these KBO shock?
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#26
Hey Joe, I've got a few orders already so production is going to begin soon. I know we talked about a setup for your NC and I haven't forgotten. I have a track day next weekend which will be a good strong test after the street driving I've been doing. You can ring or text me on my cell which I think you have.
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#27
Masa added the Eibach 24mm 'Spec Miata' front sway to Senna, increased from 22mm (OE NB) that was on there. No rear bar still.

About 30 min street drive today, car puts power down well now, very solid grip. Have a set of 225 Rivals being mounted on 15x9s that I'll be using this Saturday at Thunderhill for his first major KBO shakedown.

Getting a few sets of shocks valved today and tomm then I'll do a few more KBO customer invoices (Joe/STR and Mike/C-Street). Woo hoo!!! Excited about this weekend!
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#28
(01-28-2014, 09:05 PM)Shaikh Wrote: Have a set of 225 Rivals being mounted on 15x9s that I'll be using this Saturday at Thunderhill for his first major KBO shakedown.

You're never going to want to drive anything else. Big Grin
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