Hey guys,

Its almost too late to be asking this but I was wondering for all of you that are using Koni Yellow shocks, what do you prefer to have them set to for the track. I am running LimeRock Park tomorrow (monday) and not very sure what the optimal settings would be..

I understand your shock settings depend on alot more aspects than just the track you're on (springs, sway bars, weight, etc).. I am just looking for a push in the right direction I am using H&R OE Sport springs 1" drop, 99 Integra LS.

Granted, a few runs and re-adjustments would probably clear things up, I was thinking perhaps the more experienced crew here had some thoughts on the settings

 

Lots of variables but start with a half a turn off max on the rear and 1/2 way through the range on the front. From that point, if the car has some understeer then go to max at the rear. If the car is oversteering, soften the rebound by about 1/2 turn at the rear. If you get the balance of the car OK but the general body roll a bit much, you can try adding the same amount to the front and rear until the rear gets to max. If it is rainy or really cold and you just can't find any grip, soften it up front and rear in even amounts.

 

Depends in part on the car and how you have the chassis done. I will suggest that you start at 1 full turn and go up or down from there both front and rear. You will also be running on a much cooler track so watch the tire pressures and temps too. you are correct in assuming that it will take several laps to get a feel for the car and what it needs.
Be safe-Have fun

 

Can you adjust compression and rebound?? ...or just rebound? The single adjustable Koni yellows are REBOUND only (this is the type 99% of us have). Shock rebound mostly effects how the car handles during corner exit (after apex). When adjusting rebound only follow this:

-Car pushes during corner exit, then make the rebound in the FRONT STIFFER than in the rear.
-Car is too lose during corner exit (in a Honda, ya right!), then make the rebound in the REAR STIFFER than in the front.

I know this is backwards from what most people think, but you need to keep in mind that we are adjusting rebound NOT compression. On a car with single adjustable (rebound only) I would do the following to tune in the shocks:

1. Go full soft in the rear, then
2. Adjust the rear stiffer and stiffer until there is enough rebound damping to keep the car from bouncing up then back down. If you bounce the back end down (push it down), and the car oscillates at all, then stiffen the shocks up more. When you find the point were the car does not bounce up then back down, then donÂ’t go much stiffer than that point.
3. Now go to the front of the car and adjust the rebound to abut 90% full stiff.

This will help fight understeer as you accelerate out of a corner.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 57STS &raquo;</TD></TR><TR><TD CLASS="quote">Can you adjust compression and rebound?? ...or just rebound? The single adjustable Koni yellows are REBOUND only (this is the type 99% of us have). Shock rebound mostly effects how the car handles during corner exit (after apex). When adjusting rebound only follow this:

-Car pushes during corner exit, then make the rebound in the FRONT STIFFER than in the rear.
-Car is too lose during corner exit (in a Honda, ya right!), then make the rebound in the REAR STIFFER than in the front.

I know this is backwards from what most people think, but you need to keep in mind that we are adjusting rebound NOT compression. On a car with single adjustable (rebound only) I would do the following to tune in the shocks:

1. Go full soft in the rear, then
2. Adjust the rear stiffer and stiffer until there is enough rebound damping to keep the car from bouncing up then back down. If you bounce the back end down (push it down), and the car oscillates at all, then stiffen the shocks up more. When you find the point were the car does not bounce up then back down, then don’t go much stiffer than that point.
3. Now go to the front of the car and adjust the rebound to abut 90% full stiff.

This will help fight understeer as you accelerate out of a corner.
</TD></TR></TABLE>

Wow...Sorry but I don't think there is a single thing that is correct there other than the initial comment that most KONI Sports are rebound adjustable.

I think you generally have it backwards as most of it will go the way you want it to if you reverse the suggested turning directions. Also this is not just at exit, it is both entry and exit with some effect mid-corner in non-sweeper turns. The longer the turn is, steady state mid-corner will be more effected by sway bars.

Hand bouncing the car may be a good release for your pent up energy but it will have basically no real effect on judging the handling of the car since the human body can't really get the car up a fraction of the speed and force that the suspension will see on track. Also starting the rear rebound setting at minimum is going to pretty much guarantee an understeering car and if you start tuning from the bottom, you will lose a lot of time before you get it up near the upper ranges you will need to get the car to rotate, especially when you are on a street based performance spring with the rear rates lower than the fronts.

 

From web sight: http://website.lineone.net/~richardn/Dampers.html

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">If it's understeering when you're accelerating out of a corner, then you've got too much weight transferring to the rear too quickly. Solution - either:

3+4/3+3 stiffen the front rebound dampers (to make the front rise more slowly), or
3+3/2+3 soften the rear bump dampers (to make weight transfer go through the rear springs), or
3+4/2+3 do both.
</TD></TR></TABLE>

I know just because it's on the web dose not make it true, but I could find 10 more sights that will agree with me if I do a quick search on shock tuning. I think I remember reading about this very thing in GRM one time, but I forget which issue.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 57STS &raquo;</TD></TR><TR><TD CLASS="quote">From web sight: http://website.lineone.net/~richardn/Dampers.html

I know just because it's on the web dose not make it true, but I could find 10 more sights that will agree with me if I do a quick search on shock tuning. I think I remember reading about this very thing in GRM one time, but I forget which issue.
</TD></TR></TABLE>

his fundamentals are all wrong. he's interpreting body motion as weight transfer. if you take a wheel and look at how the shock effects the loading and unloading of the wheel you'll find this.

1) a higher compression force (stiff) will load the wheel faster
2) a higher rebound force (stiff) will unload the wheel faster
3) a lower compression force (soft) will load the wheel slower
4) a lower rebound force (soft) will unload the wheel slower

so, in a fwd car, if you are limited to only rebound adjustment you want to set the front rebound soft so the front tires unload as slow as they can on corner exit and you want to set rear rebound stiff so that the inside rear unloads quickly at corner entry.

it's the way it is. no number of incorrect websites (especially ones written to help chassis setup in a computer driving sim like GPL) will change that.

nate

ps. many people get the wrong idea about what happens with chassis dynamics by confusing the cause and effect. i've done it. it would appear that the guy on the site you linked to did too.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 57STS &raquo;</TD></TR><TR><TD CLASS="quote">
I know just because it's on the web dose not make it true, but I could find 10 more sights that will agree with me if I do a quick search on shock tuning. I think I remember reading about this very thing in GRM one time, but I forget which issue.
</TD></TR></TABLE>

I have read that site and agree with most of the information and the quote from KONI is what I have used for years about the from scratch adjustment procedure for double adjustables.

What he is describing though for his entry and exit adjustments has both some misinformation and more misapplication in it. It reads very similarly to the descriptions that we give when tuning a rear wheel drive dirt or paved circle track racer, especially the isolation of exit from entry as they are managing the weight transfer upon acceleration at corner exit from the front to rear to plant the rear drive wheels.

The entrance information is basically correct but the approach may be a bit different from what some guys are used to seeing (I remember working this out myself when I used to answer the KONI Tech Line for advising both circle track racers and road racers). The exit stuff is not at all right for a front drive car and pretty much on our cars in the situations that we are discussing, the entrance characteristics are what it is all about. Unless you are trying to work with weight transfer to the rear to control the exit tire bite on a high power rear drive car, it just doesn't apply here. Definately don't pull his exit information pretty far out of context and apply it to entrance and general cornering. If your FWD car is having a power on exit push (wish I had that much power) then the car really hasn't rotated enough at entrance and mid-corner or you have other issues like traction or torque steer. Remember a RWD car will balance with the power to get the car out of the corner fast and an FWD will have it matted and pull themselves out.

As for the GRM articles, it may be the one that I wrote several years ago but I stand by my all of my statements. I think if we polled the folks here with adjustable shocks as to hwat you want to do to make the car rotate or resist with shocks, they'll agree that adding rear rebound adds oversteer and taking it away reduces it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Definately don't pull his exit information pretty far out of context and apply it to entrance and general cornering.</TD></TR></TABLE>

I'm only talking about corner exit, nothing else. I never said anything other than corner exit. My car likes to push on exit so I tend to worry about that the most. In my car getting rotation on corner entry is not hard at all, but fighting the push on corner exit is what I’m having problems with. I was just assuming most FWD cars had this problem, I could be wrong here.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">If your FWD car is having a power on exit push (wish I had that much power) then the car really hasn't rotated enough at entrance and mid-corner or you have other issues like traction or torque steer.</TD></TR></TABLE>

I have open diff so traction is a problem on corner exit. I know it helps me accelerate out of a corner if I have the front rebound set stiff and the rear set soft (less wheel spin, and less push). Maybe after I install my LSD that will all change. *shrug*

I'm trying to understand this all better, so please tell me what's wrong with this argument. Lets assume the car is at steady state in a hard corner (the shocks are doing nothing at this point it all spring rates and sway bar), then we reach apex and start to open the wheel up and get on the gas more. Opening the wheel up yields less centrifugal force and the car will start to flatten out (less body lean). The outside suspension is now moving in the rebound direction, and the inside tires are moving in the compression direction. If the rate of rebound is slower in the front than in the back (front has stiff rebound setting), then we are effectively taking load off the front outside tire and adding load to the rear outside tire. I think of it sort of like when you corner balance a car with adjustable ride height. If you were to shorten the left front, and extend the left rear, (this is what happens temporarily as you open the wheel up after apex during a right hand turn), then you are adding weight (load) to the left rear, and right front, while taking load away from the right rear, and left front. Adding load to the outside rear tire will tend to make the car rotate more will it not?


Another quote from a “suspension 101 page” http://www.quarterscale.com/suspension_101.htm
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote"> Exit Under-steer - Increase rebound of front shocks. Decrease bump of rear shocks. Stiffen rear springs/anti-roll bar. Soften front springs/anti-roll bar. </TD></TR></TABLE>

I know this does not make it true but I like to know I’m not the only one who thinks crazy like this ya ya I know they are talking about RRD cars, but I thought the basics of suspension would apply to both.

My head hurts

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 57STS &raquo;</TD></TR><TR><TD CLASS="quote">...then we are effectively taking load off the front outside tire and adding load to the rear outside tire...
</TD></TR></TABLE>

you have it coming off the correct tire, but going onto the wrong tire. the weight will come off the outside front and go onto the _inside_ front. and we know that a more equally loaded pair of tires will generate more grip then a pair of tires not so equally loaded.

in a rwd car this is good. in a fwd car this means that weight is transferred off the front tires and onto the rears at a faster rate too.

why you might be experiencing the opposite of other fwd honda racers could be as simple as the higher front shock setting is keeping the car flatter. because the car is flatter the outside front doesn't experience as much dynamic camber loss so it generates more cornering power. the increase in front cornering grip reduces understeer which allows you to have the wheel straighter and to be able to put the power down better.

nate

 

The motions that you describe sound correct but remember that they are or should be small and subtle, especially in a well set-up car that is not just rolly and floppy. The transition from the point of highest body roll will be pretty subtle but all during this time from at or preferably well before the apex the car should be hard under power and you should be tracking out and unwinding the steering. The suspension should be mostly dealing with the acceleration issues like the inherent understeer levels of anything but an open diff, etc). Any effect that the front to rear transfer of weight should be well covered by acceleration issues.

Can you think of a single example of FWD exit oversteer that is not a direct result of driver error (drastic lift, early apex then lift, etc.)? I can't and can think of few even with those issues. Understeer yes, and that would be that there is a combination of too much steering input, early apex and/or too much power application for the level or lack of rotation by mid-corner or time that you commited to the throttle in the first place. Anyway, these are generally not subtle situations that are far enough downstream to be real shock adjustment issues.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 57STS &raquo;</TD></TR><TR><TD CLASS="quote">
Adding load to the outside rear tire will tend to make the car rotate more will it not?
</TD></TR></TABLE>

Unless that load is to the point of overloading the tire either too fast or with too much weight, it should stick the rear end better and make it want to rotate less.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 57STS &raquo;</TD></TR><TR><TD CLASS="quote">Another quote from a “suspension 101 page” http://www.quarterscale.com/suspension_101.htm
</TD></TR></TABLE>

Again this is in regards to circle track racing RWD cars and just isn't going to apply here.

 

Hey guys, completed the event today!

I ended up running 1 3/4 turns in the rear and 1 1/2 turns in the front, and it felt great! I probably could have tuned it a little bit better but I had plenty of other things to focus on Thanks for the tips, didn't menat to start a debate but great info in this thread!

 

some good info here..I don't wanna lose this thread.

Also...Thinking from my less experienced stand point..and reading this

"If it's understeering when you're accelerating out of a corner, then you've got too much weight transferring to the rear too quickly."

The reason FWD cars understeer, is because our weight bias is normally heavier upfront, along w/the fact that that is where the power is being put down..

RWD cars on the other hand *tend* to have a more neutral weight bias, and put the power down in the rear...causing oversteer.

so the statement above really doesn't make sense to me..? anyone else?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX Lee &raquo;</TD></TR><TR><TD CLASS="quote">
I think if we polled the folks here with adjustable shocks as to hwat you want to do to make the car rotate or resist with shocks, they'll agree that adding rear rebound adds oversteer and taking it away reduces it.</TD></TR></TABLE>

*raises hand*

My setup is 400f/350r w/Koni Yellows. and 3/4 stiff front and full stiff rear yields a fairly neutral rotation..as good as I have found so far.

turn down on the front, for example 1/2 stiff, my car starts to over-rotate (Oversteer)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">you have it coming off the correct tire, but going onto the wrong tire. the weight will come off the outside front and go onto the _inside_ front. and we know that a more equally loaded pair of tires will generate more grip then a pair of tires not so equally loaded.</TD></TR></TABLE>

Yes, and this is my point. I want the front to stick better, less push that way.

I'm starting to think my car responds well to stiff rebound up front because of the open diff.

I can see how stiff rebound in the rear will make the car rotate better at turn entry (I agree with you there 100%), but I'm still having trouble seeing how it makes the car loose during turn exit.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 57STS &raquo;</TD></TR><TR><TD CLASS="quote">
I can see how stiff rebound in the rear will make the car rotate better at turn entry (I agree with you there 100%), but I'm still having trouble seeing how it makes the car loose during turn exit.</TD></TR></TABLE>

Here is what I think is going on, keep in mind Im no expert.

Think of your car when you transition from off the throttle, to on (that would simulate corner exit.)

The weight from your car transitions from front, to rear. ie....the front of your car lifts, and you lose traction up front. (for a better example think of a drag racing launch )

By keeping ther rear stiff, it keeps less of the weight from shifting to the rear and more up front, therefore keeping weight over top of the drive wheels, hence more tracition and steering input are available.

*although compression would make more sense here, I believe rebound would still accomplish the same task it would just be somewhat later, in the uhhm, how do I explain it...shock cycle...is that even a concept lol *

That is my take...




Modified by DsR at 12:06 PM 11/11/2003

 

The reason you want softer rebound on the fronts is that as you get on the gas and the front end lifts, the softer rebound setting lets the suspension extend quickly along with the front end lifting so that the front tires maintain traction.

With a stiff front end rebound setting, as the front end of the car lifts, the shocks don't let the suspension extend thus slightly lifting the front tires up off the ground.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Another Drew &raquo;</TD></TR><TR><TD CLASS="quote">The reason you want softer rebound on the fronts is that as you get on the gas and the front end lifts, the softer rebound setting lets the suspension extend quickly along with the front end lifting so that the front tires maintain traction.

With a stiff front end rebound setting, as the front end of the car lifts, the shocks don't let the suspension extend thus slightly lifting the front tires up off the ground. </TD></TR></TABLE>

that doesn't make sense to me....

AFAIK Rebound *Is* the shocks extending.. w/your explanation that would mean you would want stiffer rebound so they extend *faster*..

Softer rebound would mean the shocks extend slower...

I think it has more to do w/weight transfer (F vs R) than the rate of the shocks extending...the speed that they extend would be a matter of, uhhmm nano seconds.


someone correct me if Im wrong....


D, waits for the experts to chime in

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 57STS &raquo;</TD></TR><TR><TD CLASS="quote">

Yes, and this is my point. I want the front to stick better, less push that way.

I'm starting to think my car responds well to stiff rebound up front because of the open diff.

I can see how stiff rebound in the rear will make the car rotate better at turn entry (I agree with you there 100%), but I'm still having trouble seeing how it makes the car loose during turn exit.</TD></TR></TABLE>

a high rear rebound setting won't effect the car at corner exit enough that you'll feel it. your front rebound takes over there. the idea with the higher rear rebound is that the increase in corner entry rotation can be carried into the next phase of cornerning. get enough corner entry oversteer so that you can carry it through the mid-corner and into the corner-exit phase and your car will be faster. *

and like i said, a high front rebound setting will make the fronts unload quicker upon throttle application. so, if we take our car that has crazy rotation at entry and look at what happens as we apply throttle (to catch that slide) you'll realize that the soft front shock setting will let the weight come off the fronts slower, prolonging the rotation longer into the cornering phases and hopefully into the corner exit phase.

nate

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DsR &raquo;</TD></TR><TR><TD CLASS="quote">

that doesn't make sense to me....

AFAIK Rebound *Is* the shocks extending.. w/your explanation that would mean you would want stiffer rebound so they extend *faster*..

Softer rebound would mean the shocks extend slower...

I think it has more to do w/weight transfer (F vs R) than the rate of the shocks extending...the speed that they extend would be a matter of, uhhmm nano seconds.


someone correct me if Im wrong....


D, waits for the experts to chime in </TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Solo-X &raquo;</TD></TR><TR><TD CLASS="quote">1) a higher compression force (stiff) will load the wheel faster
2) a higher rebound force (stiff) will unload the wheel faster
3) a lower compression force (soft) will load the wheel slower
4) a lower rebound force (soft) will unload the wheel slower</TD></TR></TABLE>

rebound is the direction the shock is moving. rebound force is the resistance to that motion. a higher rebound force (stiffer) will unload the tire quicker.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Another Drew &raquo;</TD></TR><TR><TD CLASS="quote">The reason you want softer rebound on the fronts is that as you get on the gas and the front end lifts, the softer rebound setting lets the suspension extend quickly along with the front end lifting so that the front tires maintain traction.</TD></TR></TABLE> correct
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Another Drew &raquo;</TD></TR><TR><TD CLASS="quote">
With a stiff front end rebound setting, as the front end of the car lifts, the shocks don't let the suspension extend thus slightly lifting the front tires up off the ground.
</TD></TR></TABLE>

there is no lifting of the tire off the ground. the weight is just removed from it quicker.

also, the _amount_ of weight transfer does not change at all, only the _rate_ of weight transfer.

nate

 

Thank god someone who knows whats going on responded.

Thanks Nate!

EDIT...you posted the same time I did..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DsR &raquo;</TD></TR><TR><TD CLASS="quote">Thank god someone who knows whats going on responded.

Thanks Nate!

Along w/what you said, the rears rebound may not have a huge difference in weight transfer when you apply throttle, but it would slow the weight transfer down, correct?</TD></TR></TABLE>

no, rear rebound will not have any effect on the fore/aft weight transfer under acceleration. the rebound force only has effect when the shock is extending (rebound).

nate-not trying to step on lee's toes.

 

now Im confused....lets play educate the n00b, ready.....go

If this is true

1) a higher compression force (stiff) will load the wheel faster
2) a higher rebound force (stiff) will unload the wheel faster
3) a lower compression force (soft) will load the wheel slower
4) a lower rebound force (soft) will unload the wheel slower

most notably #2

how is this true

"The reason you want softer rebound on the fronts is that as you get on the gas and the front end lifts, the softer rebound setting lets the suspension extend quickly along with the front end lifting so that the front tires maintain traction."

don't those statements contradict each other?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by solo-x &raquo;</TD></TR><TR><TD CLASS="quote">

no, rear rebound will not have any effect on the fore/aft weight transfer under acceleration. the rebound force only has effect when the shock is extending (rebound).

nate-not trying to step on lee's toes.</TD></TR></TABLE>


sooo. compression settings would have an effect on the *rate of weight transfer*?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by solo-x &raquo;</TD></TR><TR><TD CLASS="quote">

there is no lifting of the tire off the ground. the weight is just removed from it quicker.


nate</TD></TR></TABLE>

LOL. Maybe your car doesn't have enough mad torque to lift the front tires up off the ground. I knew that was gonna get misinterpreted. I was just being figurative.