Suspension tuning - dampers, spring rates, etc.

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Dave7CDMTYPER
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Re: Suspension tuning - dampers, spring rates, etc.

Post by Dave7CDMTYPER » Fri Aug 27, 2021 11:59 am

aw614 wrote: Fri Aug 13, 2021 8:42 pm Honed Developments just released their EG/DC Upper control arms for pre-order
https://honeddevelopments.com/product/e ... amber-arm/
Wow pretty interesting, thanks for sharing.
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Re: Suspension tuning - dampers, spring rates, etc.

Post by aw614 » Sun Sep 12, 2021 12:40 pm

I got my set a few weeks ago, just been lazy on getting the pictures of them to show. But it looks like the balljoint is easily replaceable with one like a sankei 555 one. I am curious how precise the adjustment is vs say the Skunk2 units which slide smoothly.
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Re: Suspension tuning - dampers, spring rates, etc.

Post by dcharles85 » Sat Sep 18, 2021 10:57 am

Have been looking at a handful of Honed pieces. Would love to hear your feedback once you have installed and a few miles on them.

-David

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Re: Suspension tuning - dampers, spring rates, etc.

Post by coolhandluke » Sun Sep 26, 2021 10:44 am

dcharles85 wrote:Have been looking at a handful of Honed pieces. Would love to hear your feedback once you have installed and a few miles on them.

-David
Which Honed pieces are you eyeing?
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Re: Suspension tuning - dampers, spring rates, etc.

Post by coolhandluke » Fri Jan 07, 2022 12:15 pm

Here are two clips I meant to recreate, but never did, maybe when I get a replacement track car and my new GoPro Hero 10:

Rear suspension, by Erik95LS at Autobahn Country Club at Type R Expo 10:
https://youtu.be/xNlQTAq0cS0

Front suspension, by Greg Amy at Road America for the 2013 SCCA runoffs:
https://youtu.be/C5AY4NbF29A
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Suspension tuning - dampers, spring rates, etc.

Post by aklackner » Fri Jan 07, 2022 12:52 pm

coolhandluke wrote:Here are two clips I meant to recreate, but never did, maybe when I get a replacement track car and my new GoPro Hero 10:

Rear suspension, by Erik95LS at Autobahn Country Club at Type R Expo 10:


Front suspension, by Greg Amy at Road America for the 2013 SCCA runoffs:
Very interesting to see thanks for sharing. Image

Looks like pic coilovers, ASR brace with OEM ITR ARB? Were you happy with the setup?
Do you remember spring rates?
Rear inside looks to get light to the point of lifting a bit, was this noticeable/worth doing something to address (stiffer front ARB or spring?) or would that limit travel to the point of impacting grip (maybe depends on track surface)?

Interesting to watch the geometry of the front when the body rolls hard you can see it start to lose a little bit of camber with the lca starting to swing back in more then the uca, but looks like the lca motion is centered in the arc well enough that it wouldn’t really be noticeable. If the car went lower I could see a case for an extended lower ball joint to get the lca down further.

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Re: Suspension tuning - dampers, spring rates, etc.

Post by coolhandluke » Fri Jan 07, 2022 1:45 pm

aklackner wrote: Fri Jan 07, 2022 12:52 pm
coolhandluke wrote:Here are two clips I meant to recreate, but never did, maybe when I get a replacement track car and my new GoPro Hero 10:

Rear suspension, by Erik95LS at Autobahn Country Club at Type R Expo 10:


Front suspension, by Greg Amy at Road America for the 2013 SCCA runoffs:
Very interesting to see thanks for sharing. Image

Looks like pic coilovers, ASR brace with OEM ITR ARB? Were you happy with the setup?
Do you remember spring rates?
Rear inside looks to get light to the point of lifting a bit, was this noticeable/worth doing something to address (stiffer front ARB or spring?) or would that limit travel to the point of impacting grip (maybe depends on track surface)?

Interesting to watch the geometry of the front when the body rolls hard you can see it start to lose a little bit of camber with the lca starting to swing back in more then the uca, but looks like the lca motion is centered in the arc well enough that it wouldn’t really be noticeable. If the car went lower I could see a case for an extended lower ball joint to get the lca down further.
The rear clip is Erik95LS's car. :thumbup:
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Re: Suspension tuning - dampers, spring rates, etc.

Post by DC2Iggy » Wed Feb 09, 2022 8:50 pm

What's the general consensus on extended ball joints/roll center kits? Did some looking into them this afternoon but most threads are 2010 or older and the opinions are divided. A lot of companies made/make them but Honed Developments seems to be the only one that's done "testing" and has posted their findings online.

I need to replace the ball joints on my ITR and wondering if I go with the oem length ones or go with extended ones if there are benefits. My car is slightly lowered on GC/Koni and lately it's been more of a autocross/lapping car than just daily driving. Any point of going with extended ball joints?

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Re: Suspension tuning - dampers, spring rates, etc.

Post by aklackner » Wed Feb 09, 2022 9:10 pm

DC2Iggy wrote:What's the general consensus on extended ball joints/roll center kits? Did some looking into them this afternoon but most threads are 2010 or older and the opinions are divided. A lot of companies made/make them but Honed Developments seems to be the only one that's done "testing" and has posted their findings online.

I need to replace the ball joints on my ITR and wondering if I go with the oem length ones or go with extended ones if there are benefits. My car is slightly lowered on GC/Koni and lately it's been more of a autocross/lapping car than just daily driving. Any point of going with extended ball joints?
From what I’ve consumed, it’s generally very hard to correct double wishbone geometry once lowered. If a lowered a small amount (LCAs are level or angled slightly up to the inside, under weight) I believe you’re better off running OEM ball joints.

If lowered aggressively (LCAs point down to inside), to reduce center of gravity, and running stiff race suspension then raising the roll centers (front and rear) may be desired since the shift in geometry will move the roll center further from center of gravity increasing effective roll forces.

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Re: Suspension tuning - dampers, spring rates, etc.

Post by coolhandluke » Mon Feb 14, 2022 12:44 pm

aklackner wrote: Wed Feb 09, 2022 9:10 pm
DC2Iggy wrote:What's the general consensus on extended ball joints/roll center kits? Did some looking into them this afternoon but most threads are 2010 or older and the opinions are divided. A lot of companies made/make them but Honed Developments seems to be the only one that's done "testing" and has posted their findings online.

I need to replace the ball joints on my ITR and wondering if I go with the oem length ones or go with extended ones if there are benefits. My car is slightly lowered on GC/Koni and lately it's been more of a autocross/lapping car than just daily driving. Any point of going with extended ball joints?
From what I’ve consumed, it’s generally very hard to correct double wishbone geometry once lowered. If a lowered a small amount (LCAs are level or angled slightly up to the inside, under weight) I believe you’re better off running OEM ball joints.

If lowered aggressively (LCAs point down to inside), to reduce center of gravity, and running stiff race suspension then raising the roll centers (front and rear) may be desired since the shift in geometry will move the roll center further from center of gravity increasing effective roll forces.
Honed out of the gate caught my interest since they were originally engineering driven with data. The Honed updates have been marketing oriented lately, but they have a rollcenter kit for front & rear.

Sadly, this was the project I was about to install prior to theft. My Honed kit was in the car, so I never got a chance to drive/track so I'm unable to offer direct feedback. I can ask a few that have tracked with the kit for direct / none "influencer" feedback.

The main thing these days is to get out and get seat time. I spent way too much money over the years simply because I enjoyed projects / wrenching on the car.
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