PDA

View Full Version : Adjusting Bound and Rebound



LvisDin
04-21-2008, 07:18 PM
I know cars but not that well as most here. I know that pre-built coilovers adjust the bound and rebound as the same. Most prefer custom built coilovers. I was thinking what companies offer these kind of dampers? Konis? Also how would I like to set up my bound and reboud?

mustclime
04-22-2008, 05:16 AM
Its called compression and rebound damping adjustment.....the truth be know most those adjustment knobs cause more trubble than they fix as they are not very precise. If you take your basic adjustable damper and put it on a shock dyno( a tool for reading damping of shocks), the amount of damping each knob changes can be very different.....this means to "match" the rebound for a set of say megan's, you may have to turn one knob out 4 clicks and the other 10 clicks and the only way to see this is on a shock dyno. :mfrown:

Lucid Moments
04-22-2008, 05:30 AM
Also until you get into the very, very high end race stuff you won't find much that has seperate adjustments. The good street/track stuff will have a single adjustment usually for rebound only. I don't know of anything that has seperate compression and rebound adjustments until you get into the really good stuff like Moton, and for that you are going to be paying $1k per wheel or so.

LvisDin
04-23-2008, 12:19 AM
Damn intense. Does anyone happen to know the spring rates of the Tanabe Type 2 coilovers? I checked on the spring/drop rate and I found nothing.

ep_hatcher_510
04-23-2008, 01:44 AM
Front 6.0kg/mm
Rear 8.0kg/mm

Soo after converting it, i got this

Front 335lbs/in
Rear 446lbs/in

LvisDin
04-23-2008, 01:51 AM
Front 6.0kg/mm
Rear 8.0kg/mm

Soo after converting it, i got this

Front 335lbs/in
Rear 446lbs/in

My H&Rs are about the same. Maybe I should upgrade my Tokico HP to Dspecs.

ep_hatcher_510
04-23-2008, 10:28 AM
My H&Rs are about the same. Maybe I should upgrade my Tokico HP to Dspecs.

that will def. be an improvement.:mbiggrin:

Zzyzx
04-23-2008, 10:33 AM
My H&Rs are about the same. Maybe I should upgrade my Tokico HP to Dspecs.

it may be an improvement.. it may not, only thing for certain is that you'll have a little knob to mess with.

What are you trying to tune for?

LvisDin
04-23-2008, 10:45 AM
it may be an improvement.. it may not, only thing for certain is that you'll have a little knob to mess with.

What are you trying to tune for?

Daily driving/Mountains.

Zzyzx
04-23-2008, 10:56 AM
Daily driving/Mountains.

Ok, And what were you looking to get out of moving from HP's to D-specs? I mean are the Hp's not able to deal with your H&R springs, or were you just looking for something stiffer?

And how is the car actually handling right now?

LvisDin
04-23-2008, 12:45 PM
Ok, And what were you looking to get out of moving from HP's to D-specs? I mean are the Hp's not able to deal with your H&R springs, or were you just looking for something stiffer?

Honestly. I forgot. I havent mountain raced over a year because my car is back in NorCal in the garage. Last time I remembered it handled fine on one road, but the other road is a little more rockier and my rear was slipping so I kinda want to be able to adjust with both mountains. Also I need an alignment. When my dad took it to get align it was on factory specs :mrolleyes:. But I'll see how it goes in the sumer when I actually get to take it to the mountains.

LvisDin
04-23-2008, 12:49 PM
I remember I understeered a few times but my tires werent warmed up. My rear comes in fine, but its my front. Maybe a little more stiffer in rear.

LvisDin
04-25-2008, 10:40 AM
Anyone know the spring rates on Buddy Club N+? Is it the same as the race spec?

Zzyzx
04-25-2008, 11:26 AM
I remember I understeered a few times but my tires werent warmed up. My rear comes in fine, but its my front. Maybe a little more stiffer in rear.

Softening the nose may be the better option here. Whats your alignment look like?

LvisDin
04-25-2008, 03:51 PM
Softening the nose may be the better option here. Whats your alignment look like?

Stock :mcry: When I get an alignment I plan to go reverse stock settings and go from there.

jw1
04-27-2008, 01:29 AM
If you want to change your alignment settings you are going to need some camber bolts in the front and replacement arms in the rear otherwise you are wasting your money working with the factory parts.

MugsyTheGr8
04-27-2008, 08:34 AM
here is something i found on another forum i post on regarding bump and rebounds settings.

Shock dyno explanation??? :D


KONI Civic presentation slide 1 (http://www.koni-na.com/presentations/civic/)
Stolen from \/\/\/
Honda-Tech.com: Suspension: [FAQ] Shock Dynos (http://www.honda-tech.com/zerothread?id=1104049)

http://www.koni-na.com/presentations/civic/images/Slide2.JPG
Mugen
http://www.kingmotorsports.com/images/clayton/fd2rsus.jpg
TEINS
http://img.photobucket.com/albums/v511/Ocelaris/Shock_Dynos/Tein_RAfront.jpg
Buddy Clubs
http://www.iammike.org/pictures/miscellaneous/forums/bc_rsd_front_dyno.gif
Koni
http://www.koni-na.com/presentations/civic/images/Slide3.JPG
http://img.photobucket.com/albums/v511/Ocelaris/Shock_Dynos/Slide21.jpg
http://img.photobucket.com/albums/v511/Ocelaris/Shock_Dynos/Slide22.jpg

"The different speeds in which a damper performs deals with different aspects of handling and ride quality.

Low speed Valving deals primairly with Handling, as it influences how quickly weight gets transfered around the chassis.

High speed Valving deals primairly with how the shock reacts to impacts, such as bumps and ruts....

Mid speed Valving deals a bit with both.

then you get in to Bump Valvling Vs Rebound Valving.

Bump Primiaily deals with ride quality.

Rebound Primaily deals with handling."

THese are just some dyno's and what not but you get the general idea I hope. Basically the dampers are the most important part of your suspension and without a truly high quality :omg: :thumb:



"I'll do my best to give a brief explanation of how to read shock dynos. This is a topic that could go on for pages and pages, I'll lay down the basics so atleast you know what your looking at.

That shock dyno is not a very accurate dyno. You want dynos that relate shaft speed to force. Such as this

http://www.roehrigengineering.com/images/dynogrph2quad.gif
Dynos looking like this are generally PVP, peak velocity pickoff. These tests run the shock at various peak shaft velocities. They are not continuous, discrete velocities are recorded, ie 5 m/s, 10m/s, 15 m/s, 25 m/s, ect. The force the shock exerts on dyno is then recorded, and plotted on a graph. A line is then drawn to connect the dots. This gives you a easily readable graph that can relate shaft speed (velocity at which the wheel is going up or down) and how much force the shock obsorbs from the spring. These are not very accurate though because only discrete velocities are recorded. These graphs are a good indicator of overall shock performance though, you can look at the shape of the curve and decide if its right for your application. These are the most common by far.

Anything less than 5 m/s is considered micro movements, this is movement mostly by body roll. Anything above 5 m/s is shock movement from bumps and dips in the road.

Now read this KONI Civic presentation slide 1 (http://www.koni-na.com/presentations/civic/)

That is all a PVP plot. The next type is a CVP, or continuous velocity plot. This records a complete cycle of the dyno taken. There is no longer a "connect the dots". It looks like this
http://www.roehrigengineering.com/images/dynographfull.gif

This shows you force in compression and rebound, actually it shows it to you twice. If you can picture the bottom end of the shock rotating on the outside of a pulley taht is being rotated, and the top end being fixed, you will see that with one full rotation of the pulley you will experience compression and rebound twice. This is more accurate that a PVP, but harder to read. The most important thing to pick up from this is the area inbetween the s curves. This is called hysterisis. This happens everytime you hit a bump and the suspension settles (up down up down). The hysterisis is caused by cavitation inside the shock. The more hysterisis the worse as the shocks ability to dampen the force is taken a way.

How to read curves:
Linear - very basic. Generally you want this on your rebound force. Springs are a linear force so you want a linear force to control the energy stored in a spring as it is being released from compressed. If you have a linear compression you will have too high damping with high shock speeds which will give a harsh ride and make the car feel unstable with mid speed bumps.

Digressive - Generally this is what you want for compression. You want high low speed damping to control body movement, but then as velocity increases the rate at which force increases decreases. This allows for bumps to be absorbed well and gives a better ride.

Progressive - Generally not what you want. I would imagine this is good for some type of racing, maybe dirt track racing?

Now matching up damping force to a spring rate and car is a whole nother discussion. I am now just trying to get into it. There is a lot that goes into it such as spring rate, motion ratios, ride frequency, and a whole lot more."

LvisDin
04-27-2008, 11:08 AM
^^great article.