Spring Rate Feedback

Suspension, including wheel, tire and brake.
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TheHeretic
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Spring Rate Feedback

Post by TheHeretic »

Recently put 250lb/in spring in the rear coilovers and after driving around am thinking they might be a little too much. Especially at 65mph+ the ride in the rear gets harsh. Have unknown front springs which will be updated soon. Leaning towards having a slightly higher rear spring rate and running no rear sway bar (popular on this forum). Does anyone have experience running 175lb/in FRONT and 200ln/in REAR? Primarily running around town and hitting some canyons every once in a while.
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JordanTr
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Re: Spring Rate Feedback

Post by JordanTr »

It's all in the shocks. I'm at 275 Front and 250 rear with shocks that are well matched. It's not all that harsh. No one else complains about the compliance of the ride.
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510rob
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Re: Spring Rate Feedback

Post by 510rob »

Shocks (which should always be called dampers, because that's what they are) should be matched to the mechanical system (which spring rate is a part of).

Spring with higher lb/in rates will also have a higher natural frequency. The damper is supposed to tame the natural frequency to prevent the system from 'undamped oscillation' - if the spring and the damper are mismatched, then the system is either over-damped or under-damped...

https://www.youtube.com/watch?v=sP1DzhT8Vzo

https://www.youtube.com/watch?v=99ZE2RGwqSM

Can you adjust the damping rate of your coil-overs?
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bertvorgon
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Re: Spring Rate Feedback

Post by bertvorgon »

Read this discussion starting just down from the top, where we start to discuss DAMPERS ( I called then shocks but Rob is right

http://www.the510realm.com/viewtopic.ph ... &start=105


then a continuation of the discussion

http://www.the510realm.com/viewtopic.ph ... &start=225
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funwithmonkeys
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Re: Spring Rate Feedback

Post by funwithmonkeys »

I have 300 front and 1100 rear with good dampers/shocks. I wouldn't call it harsh. Firm but not harsh, if I turn up the shocks it gets harsh pretty quick.
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Byron510
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Re: Spring Rate Feedback

Post by Byron510 »

funwithmonkeys wrote:I have 300 front and 1100 rear with good dampers/shocks. I wouldn't call it harsh. Firm but not harsh, if I turn up the shocks it gets harsh pretty quick.
Norm, as you have most recently built your suspension set up compared with most running these rates, which shock brands and models did you use front and rear for your set up? I should remember the fronts as I shortened your struts for you, but the rears I didn't talk to you about.

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funwithmonkeys
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Re: Spring Rate Feedback

Post by funwithmonkeys »

I am running the Koni 8610 race insert in the front and the QA1 from a Camero in The rear. I can get the model nubers later today.
Andy showed me a simple trick to see if your shocks are set in at least the ballpark of where they should be. Push a corner of the car down as hard as you can and it should come back up just slightly slower than it went down. I have mine set up pretty soft on the dampers because of the rough roads up here where I am.
If no one from the future comes back to stop you from doing it then how bad of a decision can it really be?
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TheHeretic
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Re: Spring Rate Feedback

Post by TheHeretic »

Well after chatting with Troy Ermish and riding in a few 510s this weekend I'm probably going with 200lb springs all the way around for now. Seems like a nice compromise between what Julian likes (175lbs) and what many 510s run which is closer to 250lbs. Still well more than double what a stock 510 used to have! Now to decide on the damper and coilover setup. Really only two leaders to me (Ermish or a custom Stance one).
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cruisey
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Re: Spring Rate Feedback

Post by cruisey »

want a set of lowered springs for a standard 510?
quick suggestions.
cruisey
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Re: Spring Rate Feedback

Post by cruisey »

Im after a set of lowered springs for a standard 510 sedan
any suggestions.
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