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Old Jun 23, 2015, 08:48 PM
  #16  
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Originally Posted by heel2toe
I'm on Ohlins and started off with the 8k/10k then did a 10k/650# both on stock valving and now have them revalved for 650#/800#. My car is my daily driver and auto-x toy and the roads around here are far from smooth especially after this past winter we had. Now I do swap on my Bilsteins for the winter but other than that rock the Ohlins the rest of the year and they are phenomenal as a dual purpose shock. I was thinking the ride was going to suck after my recent upping of rates and the revalve but have been presently surprised.

Personally I wouldn't run a square setup however I do admit that I've yet to try it so maybe Im missing out on a good thing. But I love the balance of the car as is and feel a square setup is only going to induce more understeer. As a track car to some that is preferred but in my case being that I auto-x it I like to make the back dance; it suits my driving style.

A pair of springs are cheap; its the revalve that costs money. If I were you I would keep the 10's on the front and pick up a pair of 12k Swifts or 650# Hyperco/ Eibach throw them on the rear with the stock valving and see if that suits you well. If you want more spring throw the rears on the front get some even stiffer springs for the rears and at the very least revalve the rears. That was essentially my progression however I started off with the stock springs (flipped) and ended up revalving all 4 since they were about due for a service anyway.
Yes. This is the kind of input I'm looking for! Your 650# spring is right at 11.6K, so almost what I was thinking of going with.

Do you know at what point Ohlins recommends a revalve? A 2k or 4k change in rate? If you don't mind, what did the revalve run you?

Originally Posted by Butt Dyno
Is it 2004?
Thank you for your useful contribution to my thread.

Last edited by letsgetthisdone; Jun 23, 2015 at 08:57 PM.
Old Jun 24, 2015, 06:09 AM
  #17  
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Originally Posted by letsgetthisdone
Do you know at what point Ohlins recommends a revalve? A 2k or 4k change in rate?
You have to revalve your dampers when you run out of adjustments not when you drastically change your spring rates. If you have 19 rebound settings and running at 8 (20 full stiff), going with stiffer spring might bring you up to 14 in which case you wouldn't need to revalve them. But, if you need to run something like 24, you need to send them back.
Old Jun 24, 2015, 07:10 AM
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Yeah I wanted to go with a 12k spring but didnt feel like paying double for the Swifts so instead bought Hypercos. Im told the general rule of thumb for a revalve is a swing of 4k in rates. Typically a quality damper will allow for a greater range whereas a lesser quality piece not so much and typically cant even properly dampen higher rates anyway.

But the real answer is it depends and is really when you are out of adjustment as was just noted. I found that the rears did fine with the 650's on stock valving but wasn't gunna attempt to go stiffer without a revalve. As for cost of a revalve you are looking at ~$250 per corner but that'll depend on the condition. Removing the top hat and spring before you ship them will help your case. I ended up spending <$800 to have all 4 done but mine were in great shape so I was able to save some money as they didnt have to replace much internally, it was basically some new shims and fluid.
Old Jun 24, 2015, 12:35 PM
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Originally Posted by heel2toe
Yeah I wanted to go with a 12k spring but didnt feel like paying double for the Swifts so instead bought Hypercos. Im told the general rule of thumb for a revalve is a swing of 4k in rates. Typically a quality damper will allow for a greater range whereas a lesser quality piece not so much and typically cant even properly dampen higher rates anyway.

But the real answer is it depends and is really when you are out of adjustment as was just noted. I found that the rears did fine with the 650's on stock valving but wasn't gunna attempt to go stiffer without a revalve. As for cost of a revalve you are looking at ~$250 per corner but that'll depend on the condition. Removing the top hat and spring before you ship them will help your case. I ended up spending <$800 to have all 4 done but mine were in great shape so I was able to save some money as they didnt have to replace much internally, it was basically some new shims and fluid.


That's not too bad. If Ohlins sells parts, I can rebuild/revalve them myself. I've done more than a few of their motorcycle shocks/forks.


Sounds like I'll just order them from wherever I can get the best deal, get the 650# springs and be good to go. Or get CBRD to send them 10k/12k for me...

Last edited by letsgetthisdone; Jun 24, 2015 at 12:52 PM.
Old Jun 27, 2015, 08:32 PM
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my car is pretty much a full time track car but i still drive it to and from track. i went from 10k/12k ohlins Vishnu spec, to 10k/12k AST 4100, to 10k/12k FA510, to 12k/14k FA Dreadnought, to what's on my car now, ohlins RT 12k/14k. i still drive the car to and from track. on full soft, the ride is not so harsh that makes me hate driving it. i usually don't mind firm ride, the car feels more connected to the road.

Chad has done tons of ohlins setup on Evos and other cars. i'm sure he has a lot of feedback from his clients with his suggestions.

Last edited by honda-guy; Jun 27, 2015 at 08:35 PM.
Old Jun 28, 2015, 07:31 AM
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Originally Posted by letsgetthisdone
Do you know at what point Ohlins recommends a revalve? A 2k or 4k change in rate? If you don't mind, what did the revalve run you?
-/+ 2k or 100lb/in. Ohlins DFVs are valved for 8k (~456lb/in) in the rear from the factory. Max you would want to go to is 10k (560lb/in). Any thing higher and you should consider a revalve.
Old Jul 16, 2015, 08:47 PM
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If you go with Ohlins DFVs you will need more spring than a 10k to get rid of roll and dive at least if you are running sticky tires.

I'm currently on 10K springs and they feel as smooth as stock on street but the car is borderline too soft on track with race tires.

Its always a compromise with a part time race car.
Old Jul 16, 2015, 10:19 PM
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Coilover questions

I won't ever be on a stickier tire than an NT-01 or r888. If 10k/12k yields too much body roll, I'll probably do sway bars.
Old Jul 17, 2015, 07:58 AM
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i'll have a set of FA Dreadnought double adjustable freshly rebuild with new CFD pistons up for sale in a couple days. 12k front 14k rear springs, swift springs. external reservior. on the softest settings, the FA felt more compliant than the ohlins on softest setting i have now. ohlins also 12k/14k. that was FA with old pistons. not sure how the new CFD pistons feel. but the CFD pistons are designed to allow a wide range of spring rates without needing to revalve.

http://www.fortune-auto.com/cfdinfo.htm
Old Jul 17, 2015, 08:43 AM
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Anyone have any shock dynos for their coilovers? That might help the discussion further than anecdotal descriptions.

I was interested in the Penskes because of the Regressive valve option.

I imagine a lot of these coilovers are digressive/digressive or digressive/linear.

What ever happened to Evolution Dynamics doing the suspension logging and sharing the info? Did that all fall through?
Old Jul 17, 2015, 09:46 AM
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^ all FA 510 are made to order and come with shock dyno. i can post shock dyno of the FA Dreadnought once i cut the box open, i just picked them up yesterday.
Old Jul 17, 2015, 10:00 AM
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Originally Posted by honda-guy
i'll have a set of FA Dreadnought double adjustable freshly rebuild with new CFD pistons up for sale in a couple days. 12k front 14k rear springs, swift springs. external reservior. on the softest settings, the FA felt more compliant than the ohlins on softest setting i have now. ohlins also 12k/14k. that was FA with old pistons. not sure how the new CFD pistons feel. but the CFD pistons are designed to allow a wide range of spring rates without needing to revalve.

http://www.fortune-auto.com/cfdinfo.htm

I wasn't quite ready to buy, but may be interested depending on your price.

Originally Posted by nollij
Anyone have any shock dynos for their coilovers? That might help the discussion further than anecdotal descriptions.

I was interested in the Penskes because of the Regressive valve option.

I imagine a lot of these coilovers are digressive/digressive or digressive/linear.

What ever happened to Evolution Dynamics doing the suspension logging and sharing the info? Did that all fall through?

So many things effect how damper force gets put into the chassis. Roll center (really suspension geometry camber gain/loss, etc), damper motion ratio, sprung and un-sprung corner weights, tire grip, sway bars, typical shaft speed (no one has the setup laying around to data log damper shaft speeds), etc. Knowing I own an Evo, and purchasing coil overs based on a posted damper force charts is useless because we don't actually know the shaft speeds generated by the car. You need a FULL understanding of chassis dynamics to apply the information in the dyno chart to how the chassis will act/react with those dampers. You would need damper force measurement of the shock coming off the car to even have something to compare the new stuff too, or do a decent amount of math..

The only thing you can get from a damper dyno is whether the piston is digressive, progressive, or linear.

Last edited by letsgetthisdone; Jul 17, 2015 at 10:03 AM.
Old Jul 17, 2015, 01:09 PM
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Originally Posted by letsgetthisdone
So many things effect how damper force gets put into the chassis. Roll center (really suspension geometry camber gain/loss, etc), damper motion ratio, sprung and un-sprung corner weights, tire grip, sway bars, typical shaft speed (no one has the setup laying around to data log damper shaft speeds), etc. Knowing I own an Evo, and purchasing coil overs based on a posted damper force charts is useless because we don't actually know the shaft speeds generated by the car. You need a FULL understanding of chassis dynamics to apply the information in the dyno chart to how the chassis will act/react with those dampers. You would need damper force measurement of the shock coming off the car to even have something to compare the new stuff too, or do a decent amount of math..

The only thing you can get from a damper dyno is whether the piston is digressive, progressive, or linear.
Need linear pot/acceleration logging along with shock dynos on Evos which is why I was hoping something would come from Evolution Dynamics thread.

Datalogging is next on my list after finishing the updated aero/widebody and replacing the engine. I am currently liking the idea of putting a CAN module at each corner of the car and bringing it in. I figure with the logs, I would have enough information to purchase my next set of coilovers.
Old Jul 17, 2015, 01:47 PM
  #29  
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10/12k is a good rate for the tires you'll be running. I've driven a car that had too much spring for the tire. It wasn't too fun LOL
Old Aug 2, 2016, 09:18 PM
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I found this thread and am currently in the same situation. I'm hesitant to buy Ohlins R/T as they are often a do all suspension and I would be looking for an Autox setup. I'm sure some here use their product but I'm leaning toward FA. I did make a call to them over a week ago and simply told them I use my EVO for Autox only. The rep suggested a 500 series with 10k F/ 12k R for my use. Now this with pillow bearing upgrade and FA springs which I prefer. Has there been any progress on set ups or suggestions with coilovers?

Op thanks for posting this thread been digging into this topic and trying to get as much info as possible.


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