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Old 08-31-2020, 01:48 PM   #26
SaabaRuta92x
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Quote:
Originally Posted by 2pot View Post
KW will only re-valve their competition dampers.

Are your ride heights a secret?
Lol I just measured - 14 3/4 inch front and rear. Give or take the car is parked on a slight incline.

The measurement is from the center of the wheel to the top of the fender arch.

These are the springs that the manufacturer recommended for me

https://motorsportsammo.com/products...71163027&_ss=r

https://motorsportsammo.com/products...89218166&_ss=r

Also. A vid I did on the install. I have since lowered them a bit.

https://youtu.be/PMHyYmETrV8


THANKS!!!
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Last edited by SaabaRuta92x; 09-01-2020 at 12:07 AM.
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Old 09-01-2020, 06:31 AM   #27
2pot
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Maybe pm TWF on the s2Ki forum - seems to have had some success with KW.

https://www.s2ki.com/forums/s2000-ra...982942/page10/

http://robrobinette.com/S2000KWV3.htm
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Old 09-01-2020, 10:47 AM   #28
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5 kg/mm front and 4 kg/mm rear on a GD means suspension frequencies of (roughly) 1.7 Hz front and 1.85 Hz rear. That's plenty good, not that far off flat ride, and those rates do work well on Tarmac 0s.

4.5 kg/mm front and 4 rear would probably a little over-damped up front but those suspension frequencies would be nice on a mixed tarmac and gravel street car. Closer to flat ride if that's important to you. We've not tried those rates on the Tarmac 0s for GD platform. It's also not easy to find springs at 4.5 kg but I think you can get Eibach 250 mm length. Again, haven't tried that on our Tarmac coilovers!

Flat ride is an important consideration, but not the only consideration when choosing spring rates!

Also if you're at stock height, you're too high. That can actually make ride quality worse. I'd recommend around 14.25 inches center of hub to fender for you.

Our RCE SS1 coilovers do have adjustable rebound damping and tend to ride a little smoother than our Tarmac 0s. The Tarmacs are a little more aggressive and performance focused.

Quote:
Originally Posted by SaabaRuta92x View Post
I'm sure the care needs all new bushings as well. 160k miles.
Oh my goodness yes! That is massive and I would focus on that ASAP since that will have a huge impact on how the car behaves in terms of ride and handling. There's a long list of things to inspect but basically if it's rubber or it moves, check it. Definitely start there. Let me know if you need some help.

- Andrew

Last edited by RaceComp Engineering; 09-01-2020 at 10:55 AM.
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Old 09-01-2020, 11:53 AM   #29
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Originally Posted by RaceComp Engineering View Post
5 kg/mm front and 4 kg/mm rear on a GD means suspension frequencies of (roughly) 1.7 Hz front and 1.85 Hz rear. That's plenty good, not that far off flat ride, and those rates do work well on Tarmac 0s.

4.5 kg/mm front and 4 rear would probably a little over-damped up front but those suspension frequencies would be nice on a mixed tarmac and gravel street car. Closer to flat ride if that's important to you. We've not tried those rates on the Tarmac 0s for GD platform. It's also not easy to find springs at 4.5 kg but I think you can get Eibach 250 mm length. Again, haven't tried that on our Tarmac coilovers!

Flat ride is an important consideration, but not the only consideration when choosing spring rates!

Also if you're at stock height, you're too high. That can actually make ride quality worse. I'd recommend around 14.25 inches center of hub to fender for you.

Our RCE SS1 coilovers do have adjustable rebound damping and tend to ride a little smoother than our Tarmac 0s. The Tarmacs are a little more aggressive and performance focused.



Oh my goodness yes! That is massive and I would focus on that ASAP since that will have a huge impact on how the car behaves in terms of ride and handling. There's a long list of things to inspect but basically if it's rubber or it moves, check it. Definitely start there. Let me know if you need some help.

- Andrew

Hey Andrew!

Thanks for the clarification. Yes I have been talking to some members on your team a bit. Glad to get some more clarification that this is okay to do! The whole flat ride thing goes a bit over my head...

As far as ride height goes, I am actually on spacers as well (1/2F,3/4R) and the preload for the coilover is about right in the middle so I am thinking I am prb right around where I should be.

And yes the bushing need to be changed!!! but the car has been inspected and they are in "decent" shape. But that's the next project!

Hoping these softer springs give the ride I am looking for.
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Old 09-01-2020, 11:56 AM   #30
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That's within 0.05Hz of my calculations

But, with 5/4, flat ride is going to be centred around 115mph - not bad for a track day chassis.

Whereas 5/5 - the rear frequency would be 2Hz, which is high, for a pure road car, but flat ride would be centred around 50mph - better for a road car.

For a road car, flat ride is the most important design criterion.

Last edited by 2pot; 09-01-2020 at 12:01 PM.
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Old 09-01-2020, 12:18 PM   #31
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Quote:
Originally Posted by 2pot View Post
That's within 0.05Hz of my calculations

But, with 5/4, flat ride is going to be centred around 115mph - not bad for a track day chassis.

Whereas 5/5 - the rear frequency would be 2Hz, which is high, for a pure road car, but flat ride would be centred around 50mph - better for a road car.

For a road car, flat ride is the most important design criterion.
Yeah I am prb going to go with what the manufacturer recommends on this as it doesn't seem flat ride is the one thing to focus on...But thank you for all the info!

Just out of curiosity, what does 4/4 give you?
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Old 09-01-2020, 02:13 PM   #33
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doh, wrong name.
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Old 09-01-2020, 02:14 PM   #34
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doh again!
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Old 09-01-2020, 02:15 PM   #35
RaceComp Engineering
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Quote:
Originally Posted by 2pot View Post
That's within 0.05Hz of my calculations

But, with 5/4, flat ride is going to be centred around 115mph - not bad for a track day chassis.

Whereas 5/5 - the rear frequency would be 2Hz, which is high, for a pure road car, but flat ride would be centred around 50mph - better for a road car.

For a road car, flat ride is the most important design criterion.
I disagree! But that's okay. Shaikh and FatCat are great (and I'm glad to be having a discussion on here for once...facebook sucks).

- Andrew
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Old 09-01-2020, 02:15 PM   #36
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Quote:
Originally Posted by SaabaRuta92x View Post
Hey Andrew!

Thanks for the clarification. Yes I have been talking to some members on your team a bit. Glad to get some more clarification that this is okay to do! The whole flat ride thing goes a bit over my head...

As far as ride height goes, I am actually on spacers as well (1/2F,3/4R) and the preload for the coilover is about right in the middle so I am thinking I am prb right around where I should be.

And yes the bushing need to be changed!!! but the car has been inspected and they are in "decent" shape. But that's the next project!

Hoping these softer springs give the ride I am looking for.
The spacers make sense.

It's a lot of mileage so I would definitely take a close look at them. Tire/wheel package also important.

- Andrew
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Old 09-02-2020, 06:33 AM   #37
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Just out of curiosity, what does 4/4 give you?
You might as well have used a strut set-up - why didn't you?
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Old 09-02-2020, 08:33 AM   #38
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Quote:
For a road car, flat ride is the most important design criterion.
Quote:
Originally Posted by RaceComp Engineering View Post
I disagree! But that's okay. Shaikh and FatCat are great
I think you first have to pick a range of ride frequencies - and a target flat ride speed - before getting into flat ride math. And I really think for a performance-oriented setup one should be working with damped ride frequencies, which are slightly/somewhat lower than the undamped frequencies that most of the people who talk about flat ride at all are dealing with.

IOW, flat ride considerations should perhaps be taken as different boundary lines to a problem in linear programming rather than the primary driving input. A more complete solution should probably be considering the absolute frequencies, damping, and speeds consistent with the intended use.


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Old 09-02-2020, 09:46 AM   #39
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I think you can simplify it further than that:
Rear frequency - 1.8Hz for smoother roads, front frequency to deliver flat ride at 60mph.
Rear frequency - 2 Hz for occasional track day car, driven to circuit, front frequency to deliver flat ride at 100mph.
Be advised that the 2Hz rear will give less grip on the road.
Also be advised, that ill-chosen damping will then undo all the good works done, when selecting the spring rates.

Last edited by 2pot; 09-02-2020 at 11:05 AM.
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Old 09-02-2020, 01:02 PM   #40
SaabaRuta92x
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You might as well have used a strut set-up - why didn't you?
LOL I ask myself the same question. I have never had any experience with coilovers and the RCE's seemed like a great alternative. Realistically I should have gotten a gravel spec suspension. The car handles like its on rails but I have my Z for that...

Im confident that putting on the 5/4k springs will get me where I want!

We'll see...
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Old 09-17-2020, 09:27 PM   #41
SaabaRuta92x
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Originally Posted by RaceComp Engineering View Post
The spacers make sense.

It's a lot of mileage so I would definitely take a close look at them. Tire/wheel package also important.

- Andrew
What do you think about something like this

Front
https://www.summitracing.com/parts/eib-100025300250

Rear
https://www.summitracing.com/parts/e...RoCywAQAvD_BwE

Ideally I would revalve but not possible with with these KWs...

Thanks!
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Old 09-18-2020, 11:18 AM   #42
RaceComp Engineering
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Quote:
Originally Posted by SaabaRuta92x View Post
What do you think about something like this

Front
https://www.summitracing.com/parts/eib-100025300250

Rear
https://www.summitracing.com/parts/e...RoCywAQAvD_BwE

Ideally I would revalve but not possible with with these KWs...

Thanks!
Got your PM, messaged you back.

Those are the wrong inner diameter but I think I have something for you.

- Andrew
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