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takaii
12-10-2017, 08:06
I have tried to read in game explanation about each damper settings... i really dont get it at all.


Could someone try explain the following

-Bump stop
-Slow bump
-Fast bump
-Bump transition

-Slow rebound
-Fast rebound
-Rebound transition

What does each thing do?
Sry to sound stupid to ask this but english isnt my strong language and i really need some better explanation than ingame covers.

cpcdem
12-10-2017, 09:14
I am sure blinkngone and others can give us some very nice explanations. Some time ago, I had a go through this (and other videos in the series):

https://www.youtube.com/watch?v=i3pntCUZh08&index=5&list=PL8vLMSxw70-yuJO3dUuwlaV423MOhPUiN

also gives plenty of info and in a visual way as well.

blinkngone
12-10-2017, 11:21
I have tried to read in game explanation about each damper settings... i really dont get it at all.



What does each thing do?
Sry to sound stupid to ask this but english isnt my strong language and i really need some better explanation than ingame covers.

They are not stupid questions, although you really need to look at Google/plenty of suspension videos.

Well first just use Google and put in "bump stops", they are basically rubber/polymers that are on the shocks to balance your cars attitude(when using softer springs/shocks/dampers and rollbars Nascar style).

What you could do takaii is study up on the suspension questions you have and leave the dampers section alone in game(Jussi has given you these using his calculator) until you have mastered 1st driving, using default loose and stable. Then going into each of the other tuning pages before you try adjusting the damper page.
The first page to work on would be this.
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Then this page. The reason I have the LSD next is because a quick adjustment here can really help if you are having trouble with your car spinning under braking or acceleration.
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This.
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and finally this.
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Johann26
12-10-2017, 12:08
I copied this from a diffrent forum hope it helps !

Softer springs = more grip but also more skid = a bit slower. Stiffer springs should make you faster but only if you drive on the limit, if not they'll just make you loose control easier.

Bump/Rebound:
Slow (bump/rebound)= your steering input. Low value means that it takes more time for the spring to absorb or rebund giving you more grip or a more stable car over bumps (really depends on track and driving style).
Fast(Bump/rebound) = feedback from the track, level changes, bumps,curves, same ideea here as above.
This is what i understand but spring/bump/rebound are one of the hardest thing to set up properly cuz the changes are very small and they generaly show up in better times not feel (that's if you don't change them by more than 2 clicks). If you maxx them out (high/low) tha car will react very diferently.

Dampers counteract the springs' natural compressing and decompressing by resisting those forces. Dampers do this via hydraulic fluids being pushed through small valves inside the damper while the damper is in motion. A higher damper value equates to greater resistance.

A wheel's maximum grip level will be achieved when the spring is fully compressed. This is when that wheel has maximum weight being transfered through the suspension, tire, and to the track. In a generic sense that weight equals grip. How quickly or slowly that spring is allowed to fully compress is the job of the damper. Springs may dictate HOW MUCH weight is transferred, dampers dictate HOW and WHEN that weight is transferred.

The easiest way to begin to understand dampers is in a straight line, under braking or acceleration:

Under braking, much of the car's weight will shift from the rear of the car to the front. The front springs will compress while the rear springs will decompress (or rebound). The dampers do the same and will compress (front) and decompress (rear). The faster the front springs are allowed to achieve their most-compressed state, the faster the front tires will have maximum grip for that all important braking. A softer compression setting will give the least amount of resistance to the spring compressing, allowing weight to transfer very quickly once the brakes are applied. The rear damper compression setting will have no effect on what happens here, but the rebound will. A greater rebound setting will resist against the rear springs decompressing. If the spring is not allowed to rebound quickly, the rear tires will be somewhat lifted off the ground (exaggerated of course). Softer rebound settings in the rear will allow the rear tires to stay connected with the road and offer more rear-grip during that weight transfer to the front.

Under straight-line acceleration the complete opposite is happening, with the rear dampers compressing and the front dampers decompressing. Surely you will want maximum grip on the rear tires under acceleration, but the front tires may need grip adjustments to prevent understeer oversteer. You can adjust this condition by adjusting how the rear suspension compresses or how the front suspension rebounds.

The same philosophy can be applied laterally (side to side) as well. Long sweeping corners that do not involve large braking or accelerating will shift weight to the left and right of the car. How fast you allow that weight to transfer is up to you and can be adjusted via the left and right dampers, but keep in mind how that will also effect your front to rear damping.

If your car is equipped with fast-damping adjustments, everything above still applies but only when the suspension is in "fast motion". An example of your suspension moving in fast-motion is when you are hopping over curbing, something I like to call "curb smacking". This is when you are shocking the suspension into movement in a very short time frame. Hitting a curb at speed (like you might at Monza, or the final chicane at Magny-Cours) is forcing your suspension to compress or rebound in a much shorter time frame than normal weight transitions. This is where fast-damping comes into the mix

blinkngone
12-10-2017, 12:23
I have tried to read in game explanation about each damper settings... i really dont get it at all.



What does each thing do?
Sry to sound stupid to ask this but english isnt my strong language and i really need some better explanation than ingame covers.

Hi takii, English is my only language.
I am giving you a link to the Project Cars 1 Garage, at the top of that forum there are numerous stickies involving your suspension questions.

http://forum.projectcarsgame.com/forumdisplay.php?117-The-Garage-Car-Setup-Talk

Casey Ringley
12-10-2017, 14:30
The big new addition for PC2 in this area is the setting for transition force. This essentially controls the valve which sets when the damper moves from slow rates for bump/rebound to fast rates. What this does is give you better control over the damper tune for what you want out of the setup. (it also lets us get a much closer match to real damper adjustments for many cars) Showing some damper dyno plots from the Clio Cup below as it's a good example matched to real data where the compression damping does rate change at constant transition force while rebound damping changes both the rates and transition force by a large amount.

Orange line shows increasing bump stiffness of the front damper. Note how the kink in the force line happens at the same vertical position for all settings. So we've gone up 5x in slow bump damping rate (something you would definitely feel in steering response!) but overall force from the damper at typical shaft velocity only goes up by 40-50%, meaning it won't be a huge difference for high speed bumps like kerb strikes and such.
Say you have a car that handles pretty well overall but you want a bit sharper input from small steering inputs. This would be one way to approach this would be tuning for that situation. Conversely, say you like the initial steering feel but find the car moves too much after that input, the outside front compresses too much and then has to spring back. In this case, you might want to keep rates the same but increase transition force for a damper with the same basic properties while being stiffer overall.
242582

The rebound damping, however, increases the slow rate by almost 9x while also stiffening the blow-off valve that controls bypass flow to the fast damping circuit. You can see that the slope of each segment of the yellow line increase, and the transition knee also rises vertically on the plot significantly from softest to stiffest settings. This side of the damper isn't just changing feel of one particular area but stiffening the whole damper by 150% or more.
242583

Visceral_Syn
12-10-2017, 15:25
In a nutshell, the fast bump/rebound controls the springs response from the track. the slow bump/rebound controls the springs response from driver input.

RomKnight
12-10-2017, 15:30
In a nutshell, the fast bump/rebound controls the springs response from the track. the slow bump/rebound controls the springs response from driver input.

And the transition force changes when it happens :P

Visceral_Syn
12-10-2017, 15:33
Lower numbers mean less resistance, also translate to faster transition. So if you want fast transitions, low number, slower transitions, higher numbers. Knowing when and where you would want the different transitions is the trick.

DECATUR PLAYA
12-10-2017, 15:52
Definitely not a stupid question as dampers may be the most complicated part of tuning. I have seen dampers referred to as the Black Arts of tuning. I can't explain them as others have above but what I will say is that I normally tune my dampers last after I get the rest of the setup as good as I think I can get it. Normally I can find another second in the damper settings. I like to call it finishing speed. Im still a little lost with the transitions as they seem like a fine tuning adjustment of the dampers.

RomKnight
12-10-2017, 15:53
That's why there's engineers.. it takes a degree to understand this :D

Visceral_Syn
12-10-2017, 15:59
Definitely not a stupid question as dampers may be the most complicated part of tuning. I have seen dampers referred to as the Black Arts of tuning. I can't explain them as others have above but what I will say is that I normally tune my dampers last after I get the rest of the setup as good as I think I can get it. Normally I can find another second in the damper settings. I like to call it finishing speed. Im still a little lost with the transitions as they seem like a fine tuning adjustment of the dampers.

You really should start tuning at the dampers. Once you have the rough spring settings for the track where you want them, the slow and fast bump/rebounds are to fine tune the springs for how you drive on the track. Example, medium soft springs at CotA, with fast damps set fairly high, will allow for the smooth surface at CoTA, and those mad S's and setting the slow bump/rebound to a soft setting should allow for a newish driver to learn to perfect the line on the track.

Roger Prynne
12-10-2017, 16:02
Great post and explanation as usual Casey, and those gifs are brilliant.

blinkngone
12-10-2017, 16:26
Great post and explanation as usual Casey, and those gifs are brilliant.

Hi Roger, thanks for the new Garage. Are you going to make Casey's explanation a sticky. Also Jussi's LSD and Suspension Calculator?

Please.

blinkngone
12-10-2017, 16:31
In a nutshell, the fast bump/rebound controls the springs response from the track. the slow bump/rebound controls the springs response from driver input.
Thanks Visceral Syn,

I drive with one arm and I mostly go to front slow bump first and lower it a couple clicks because I think I feel the wheel response better for steering. What do you think? Wrong way or right way?

Bealdor
12-10-2017, 16:39
Hi Roger, thanks for the new Garage. Are you going to make Casey's explanation a sticky. Also Jussi's LSD and Suspension Calculator?

Please.

Done.

blinkngone
12-10-2017, 16:43
What? THANKS Bealdor!

Can you make the WR holder at SPA in the Ford GT GTE?;)

Roger Prynne
12-10-2017, 16:43
Done.

^ So you've changed your name to Roger now ;)

Bealdor
12-10-2017, 16:45
^ So you've changed your name to Roger now ;)

It's not my fault when you're slower than a snail. :p

Visceral_Syn
12-10-2017, 16:51
Thanks Visceral Syn,

I drive with one arm and I mostly go to front slow bump first and lower it a couple clicks because I think I feel the wheel response better for steering. What do you think? Wrong way or right way?

Spring settings really depend on the track. I find I use stiffer/slower Slow bumps on tracks where I need to brake hard and long, like Parabolica at Monza...

Roger Prynne
12-10-2017, 17:07
It's not my fault when you're slower than a snail. :p

I was just about to do it the same time as you but the threads weren't there anymore :playful:

DECATUR PLAYA
12-10-2017, 19:06
You really should start tuning at the dampers. Once you have the rough spring settings for the track where you want them, the slow and fast bump/rebounds are to fine tune the springs for how you drive on the track. Example, medium soft springs at CotA, with fast damps set fairly high, will allow for the smooth surface at CoTA, and those mad S's and setting the slow bump/rebound to a soft setting should allow for a newish driver to learn to perfect the line on the track.

Will take this into consideration for the future.

Jussi Karjalainen
12-10-2017, 20:40
For me dampers and springs go hand in hand at the same time. If I start from a balanced position, every spring change usually requires a damper change. Dampers are there to control the springs and the body.

Hence why I use the calculator. =)

Racefancy
13-10-2017, 02:44
I agree best way to start is to use Jussi's calculator, select your springs (from a ride frequency you desire) and the damper settings result from that, this is how it's done IRL as well and it gets you in the ballpark where testing on track is then used to refine the settings.

Dynomight Motorsports
16-10-2017, 23:54
That's why there's engineers.. it takes a degree to understand this :D

In all honesty, I appreciate the games attempt to make this a very detailed and in-depth Sim, but in Real Life the Driver rarely has to deal with this many aspects of the car. They have teams of engineers for this, unless you are in some low budget hobby racing series. But the "Ask the Engineer" setting doesn't really go in-depth with dampers or tow or camber. Instead we're force fed a steady diet of info and asked to not only drive the car but be the lead Engineer as well.

tekQ
17-10-2017, 17:32
I just got PCars2 last night and my initial impression is that the developers made a complicated system even more complicated. Iíve played multiple driving sims over the last 20 years and I d never come across one that is so needlessly difficult to play. Iím probably the easiest person to please with a game, but the tuning options Iím seeing the on the Clio Cup car are so limited itís ridiculous.

Also, the responses to questions in here are no more than links to other articles that do t appear to provide any answers, they just speak in very general terms using only a definition of vocabulary as opposed to instructions on how to actually tune a car.

Honestly, I think I want my money back...

Visceral_Syn
17-10-2017, 17:35
No 2 people drive cars the same, the more you know on how to setup your car, the more you 'should' be able to get more out of the car, especially if you set up your car the way you need it to go fast...

Wayne Kerr
17-10-2017, 17:42
In all honesty, I appreciate the games attempt to make this a very detailed and in-depth Sim, but in Real Life the Driver rarely has to deal with this many aspects of the car. They have teams of engineers for this, unless you are in some low budget hobby racing series. But the "Ask the Engineer" setting doesn't really go in-depth with dampers or tow or camber. Instead we're force fed a steady diet of info and asked to not only drive the car but be the lead Engineer as well.

Depends on the series. Factory efforts wec, sure there might be teams of engineers.

Privateer LMP2 teams? Depends on the size of the team and the budget that they operate on.

If you filter it down to privateer GTD in IMSA that is not a factory backed program, I assure you the "teams" of engineer is at MOST two-three guys per car if that. Usually two is the norm, one data guy, one main engineer. You might have a junior eng that shadows the main guy and helps out the data guy in some places, but if you think every team that goes out there racing on tv has another team at the factory running a 7 post rig with telemetry getting fed back to the rig in real time, you're in for a surprise. That stuff only happens in F1.

Roger Prynne
17-10-2017, 18:38
Guys it is a 'Sim' after all.

Dynomight Motorsports
18-10-2017, 02:07
Depends on the series. Factory efforts wec, sure there might be teams of engineers.

Privateer LMP2 teams? Depends on the size of the team and the budget that they operate on.

If you filter it down to privateer GTD in IMSA that is not a factory backed program, I assure you the "teams" of engineer is at MOST two-three guys per car if that. Usually two is the norm, one data guy, one main engineer. You might have a junior eng that shadows the main guy and helps out the data guy in some places, but if you think every team that goes out there racing on tv has another team at the factory running a 7 post rig with telemetry getting fed back to the rig in real time, you're in for a surprise. That stuff only happens in F1.
Touche.. but I'm on console, and can't get VRHive to work.. so I don't even have the benefit of raw data to interpret with my "Engineering Degree". Again.. I appreciate the opportunity to tune every aspect of the car or the fact that it needed to be seriously over complicated this year over last, but when it comes to Driver Comfort, the Driver is 9 out of 10 times not looking at telemetry data trying to adjust his dampers. He simply informs the Engineer what the car is doing.

Me hitting :jaded:[Sarcasm] button; I guess I could send my wife to College and get a degree in mechanical engineering then she can cypher out the data as I drive and when I give her feedback on what the car is doing maybe the two of us can figure out how to go fast.
I know about low budget teams, I raced as a hobby till it became too expensive. But the most I could adjust was corner weight with coil-overs and tyre pressure. It was all done with the seat of my pants, and yet somehow I still managed to stay competitive. :surprise:

rpstar
26-10-2017, 20:17
I get your frustration but don't know what to say. If you want a true sim then this complexity comes along for the ride. The default setups help a lot along with the calculators. They can't do everything as you obviously know since it's all driver dependent. Other than some super Engineer AI it seems the choices are 1) dumb it down or 2) suck it up.

Marcos Riffel
09-11-2017, 00:23
The big new addition for PC2 in this area is the setting for transition force. This essentially controls the valve which sets when the damper moves from slow rates for bump/rebound to fast rates. What this does is give you better control over the damper tune for what you want out of the setup. (it also lets us get a much closer match to real damper adjustments for many cars) Showing some damper dyno plots from the Clio Cup below as it's a good example matched to real data where the compression damping does rate change at constant transition force while rebound damping changes both the rates and transition force by a large amount.

Orange line shows increasing bump stiffness of the front damper. Note how the kink in the force line happens at the same vertical position for all settings. So we've gone up 5x in slow bump damping rate (something you would definitely feel in steering response!) but overall force from the damper at typical shaft velocity only goes up by 40-50%, meaning it won't be a huge difference for high speed bumps like kerb strikes and such.
Say you have a car that handles pretty well overall but you want a bit sharper input from small steering inputs. This would be one way to approach this would be tuning for that situation. Conversely, say you like the initial steering feel but find the car moves too much after that input, the outside front compresses too much and then has to spring back. In this case, you might want to keep rates the same but increase transition force for a damper with the same basic properties while being stiffer overall.
242582

The rebound damping, however, increases the slow rate by almost 9x while also stiffening the blow-off valve that controls bypass flow to the fast damping circuit. You can see that the slope of each segment of the yellow line increase, and the transition knee also rises vertically on the plot significantly from softest to stiffest settings. This side of the damper isn't just changing feel of one particular area but stiffening the whole damper by 150% or more.
242583


Could you make an easier explanation? What u said looks very important, but it's overmind and i'm not really understanding. Could u do some examples, showing us some practice applications? Like what should happen if i increase the transition force at a gt3 car in a corner. Hope u see this.

Don-09141955
14-11-2017, 18:49
I just HAVE to ask this question.........WHAT did you think you were getting, when you purchased this game? How could you not love it?

Jussi Karjalainen
01-12-2017, 00:18
Could you make an easier explanation? What u said looks very important, but it's overmind and i'm not really understanding. Could u do some examples, showing us some practice applications? Like what should happen if i increase the transition force at a gt3 car in a corner. Hope u see this.This will depend on what the car is doing now (since most cars have the transition in a different spot). Basically increasing the transition force value will usually* increase the overall damping force, especially for cornering, braking, accelerating etc., since what it does is increase the effect of the slow setting, and the slow setting is usually stiffer.

The best way to visualize this is probably to use my calculator, where you can see the effects of all the settings in graphical form. Links are in my signature.

AEIDOLONE
26-01-2018, 17:24
Sorry if this has been answered somewhere, been searching, but can someone explain WHAT is happening when the suspension bar+travel flashes red???

249149

I mean, even Yorkie in his Insider's Guide video wasn't 100% sure what's it about...

Albertsen
26-01-2018, 18:13
Someone please stick this thread. :eagerness:

leaky
24-02-2018, 12:09
Sorry if this has been answered somewhere, been searching, but can someone explain WHAT is happening when the suspension bar+travel flashes red???

249149

I mean, even Yorkie in his Insider's Guide video wasn't 100% sure what's it about...

When the suspension bar flashes red, it indicates your springs are reaching maximum compression.

Jussi Karjalainen
24-02-2018, 15:32
When the suspension bar flashes red, it indicates your springs are reaching maximum compression.Or at least that you're touching the bump stop. And touching the bump stop isn't necessarily a big deal. =)

Gav88888
26-02-2018, 10:45
I always wondered about the suspension when it flashes red, thanks. As for dampers, I leave them as standard... ;)

Rafaellongbeach
21-03-2018, 15:39
The big new addition for PC2 in this area is the setting for transition force. This essentially controls the valve which sets when the damper moves from slow rates for bump/rebound to fast rates. What this does is give you better control over the damper tune for what you want out of the setup. (it also lets us get a much closer match to real damper adjustments for many cars) Showing some damper dyno plots from the Clio Cup below as it's a good example matched to real data where the compression damping does rate change at constant transition force while rebound damping changes both the rates and transition force by a large amount.

Orange line shows increasing bump stiffness of the front damper. Note how the kink in the force line happens at the same vertical position for all settings. So we've gone up 5x in slow bump damping rate (something you would definitely feel in steering response!) but overall force from the damper at typical shaft velocity only goes up by 40-50%, meaning it won't be a huge difference for high speed bumps like kerb strikes and such.
Say you have a car that handles pretty well overall but you want a bit sharper input from small steering inputs. This would be one way to approach this would be tuning for that situation. Conversely, say you like the initial steering feel but find the car moves too much after that input, the outside front compresses too much and then has to spring back. In this case, you might want to keep rates the same but increase transition force for a damper with the same basic properties while being stiffer overall.
242582

The rebound damping, however, increases the slow rate by almost 9x while also stiffening the blow-off valve that controls bypass flow to the fast damping circuit. You can see that the slope of each segment of the yellow line increase, and the transition knee also rises vertically on the plot significantly from softest to stiffest settings. This side of the damper isn't just changing feel of one particular area but stiffening the whole damper by 150% or more.
242583

Congratulations for your rich post. There is some place where i can find the calculator? thanks

AbeWoz
21-03-2018, 15:44
http://forum.projectcarsgame.com/showthread.php?54023-Project-CARS-2-Suspension-Calculator-v0-9

BionicBacon
29-03-2018, 00:27
https://youtu.be/CJ7O6HQBGYU

Lakiboom
18-09-2018, 11:44
I saw a lot of videos about dampers, read many topics, tried calculator. My problem - I don't feel the difference at all! Maybe there is a good car and track as example to feel? Cause I tried to change dampers in GT3, Ginetta, Touring and nothing for me.

Bealdor
18-09-2018, 11:53
I saw a lot of videos about dampers, read many topics, tried calculator. My problem - I don't feel the difference at all! Maybe there is a good car and track as example to feel? Cause I tried to change dampers in GT3, Ginetta, Touring and nothing for me.

Try the Audi R18 2016 (Fuji) @Catalunya with default loose setup first and abuse the kerbs.
And then try the same with this setup:

260116

If you still don't feel a difference I don't know what to say. :p

Thanks to damper adjustments I could transform that car into a kerb eating monster and this setup isn't even really optimised yet.

Edit: Set downforce to 7/8 or 7/9 and raise the rear ride height by ~10mm.

Zeratall
18-09-2018, 15:36
I saw a lot of videos about dampers, read many topics, tried calculator. My problem - I don't feel the difference at all! Maybe there is a good car and track as example to feel? Cause I tried to change dampers in GT3, Ginetta, Touring and nothing for me.

Lakiboom, what are you trying to "feel"? Are you just driving around to see the difference or are you looking for something specific I.e kurb handling, transient response, etc? When it comes to dampers there are really 2 regions and 2 components for each region. The two regions are:

High speed, and Low Speed damping what damping setting your in depends on the velocity of the damper, and your transition force. (damper will remain in low speed, until the force of the damper exceeds the transition force, which then causes it to kick into high speed settings.

and then the two components of the damper are:

Bound (Compression), Rebound (Extension) Bump controls the unsprung mass, that is the weight that's not supported by the spring (wheel hub, tires, etc). Rebound controls the sprung mass, that is weight that is supported by the spring (chassis,driver,etc)

From Bealdors example above you can see his bump damping is lower than his rebound damping, this will cause a suspension that will allow bump absorption (soft unsprung) but will have good chassis control (stiff sprung). This is what you call a rebound bias and is very common you just have to be careful with jacking down if your rebound bias is too high.

OptimumG (IRL Race Engineering Service for hire) recommend the following for a good baseline rebound bias.

260117

Also dampers affect cornering at transient. Transient is the portion of the turn where the chassis is still not set, so essentially corner entry, and corner exit. In the graph below we can see the suspension components of the car and how they contribute to lateral stiffness. The beginning of the turn we can see a damping force (bump) comes into play, then damping cuts out (car is set at mid corner), and then when the car exits we then again have a damping force (rebound). Althought damping doesn't apply the highest force, it does respond the soonest. That is to say, its time constant is significantly less than springs and arbs, this is why if you have adverse transient behavior (corner entry, corner exit), messing with the dampers can be very beneficial.

260118


If you have any more questions please feel free to join us over at the RST discord, we have about 400 members dedicated specifically to the science behind car tuning.
https://discord.gg/w2MeTey

Lakiboom
01-10-2018, 08:55
Try the Audi R18 2016 (Fuji) @Catalunya with default loose setup first and abuse the kerbs.
And then try the same with this setup:

260116

If you still don't feel a difference I don't know what to say. :p

Thanks to damper adjustments I could transform that car into a kerb eating monster and this setup isn't even really optimised yet.

Edit: Set downforce to 7/8 or 7/9 and raise the rear ride height by ~10mm.

Thanks. I'll try once more with racing wheel in evening, cause with quick test with gamepad I don't see the difference. Maybe it just a little bit smoother or I just try to find something after setup :)


what are you trying to "feel"? Are you just driving around to see the difference or are you looking for something specific I.e kurb handling, transient response, etc?

When I set rear aero to 0 I have an oversteer. I feel it and I see it. When I set castor to higher numbers - wheel becomes stiffer on high speed, lower numbers - softer and better handling at slow corners. Camber - I always check telemetry and I see temperatures. But with dumpers another story. As I said I tried to set it to min and max and I don't know. I don't feel the effect of this changes while driving. Is it better or worse

hkraft300
01-10-2018, 09:09
Damper adjustment is almost impossible to feel on game pad and difficult to discern on a wheel. The feel will depend on your ffb settings somewhat.
The spring balance is again easy to feel on game pad and wheel because it directly affects the balance. On a smooth race track it's also hard to feel damping changes because the dampers aren't doing all that much work.

Dampers act on the rate of spring or wheel movement. That's a very small fraction of time where you turn the wheel and the car leans and compresses the springs, then you straighten the wheel and the car straightens and the springs extend. It's only during that compression and extension period that slow damping (generally) is acting. That's not even including pitch and roll from brake/throttle. You can set springs soft and compare dampers stiff vs soft then take a chicane: you will feel the transition rate is different.
Good damping will keep the car planted through transitions, kerbs and bumps but it's a small change.
Small changes add up to that 0.01s gain.

em_t_hed
18-10-2018, 16:56
This is an awful topic in general, suspension and damping in project cars. I don't mean anyone speaking here. BUT from the 1st Project Cars... suspension and damping tuning would give you Units to work with. N/mm or something like that. In this regard, the game gives you the weight of the vehicle in total minus the driver. What the game doesn't give are mass values in the form of car frame, car body, driver, etc and tire mass. These numbers are sort of important in the suspension and damping.

I'll explain...

Slow bump/rebound are for the car body
Fast bump/rebound are for the tires

IF you drive from inside the vehicle, and you notice your front end bouncing after hitting a bump on pavement and the pavement is smooth after that bump, but the car still bounces, then you should think about adjusting the Slow Rebound. Slow = Car. The same goes for the rear. Drive in 3rd person POV, if the same bounciness happens Slow Rebound for the rear. It's a smooth road after the bump, the car should not still be bouncing during the smooth pavement. Increase Slow Rebound.

IF Slow Rebound is TOO STRONG. Depending on the strength of your dampers, it's possible you might think you have a great driving car UNTIL you're in a high speed bend in the road, you need to do some evasive maneuvering, you turn your wheel real fast, the car responds, BUT then you cant correct for your adjustment. Now the dampers are holding the springs compressed longer because the dampers are too strong. Now your in a J turn with no control no matter how you counter steer.

Fast Bump/Rebound, Haptic feedback of the road in your wheels force feedback.

Going back to the concepts of Mass with tires and vehicle body. Well.... F=M*V

The game fuct everyone in this regard.

EDIT: Watch a replay of one of your drives, watch your car from the side. You can see the car tires moving quite rapidly vertically but the car above the tires doesn't have the same fast vertical motion. Fast vs Slow respectively.

Twinz
18-10-2018, 20:01
I have been using Koni sport shocks (aka "Koni Yellows") for years on various cars that I compete with. The yellows are simple rebound-adjustable shocks.

With these shocks, the rebound adjustment is most noticeable when transfering between the front and back end of the car (as apposed to side to side transitions)

The rears basically control how much weight is initially transfered to the front tires when braking. If my car has trouble turning-in on corner entry, I "soften" the rear shocks' rebound.

The front shocks' rebound adjustment helps tune rear traction when powering out of a turn. If I feel like I have to wait forever for throttle out of turn or I'll kick the back end out, I soften the front shocks and the rear hooks up better on initial throttle.

On the flip side, if the car seems to only go straight when I try to throttle out of a turn, I tighten the front rebound and the car is more willing to rotate out of a turn.

For my specific use (Autocross) The adjustments are more cross-corner weight-transfer adjustments than simple front-rear weight transfer. (I almost never get to transition between brakes and throttle in a straight line)

My only RL experience with fancier shocks that have more adjustments is limited to co-drives in other people's cars...and I seldom did more than communicate what the car felt like to me and let them make changes as they saw fit.

Jarben
12-06-2019, 00:03
I'm still trying to understand the effect of stiffer slow rebound. I do know it resists spring expansion. But there are sources claiming that stiffer rebound keeps weight in that particular corner of the car while softer distributes it elsewhere, and then there are sources claiming that stiffer rebound unloads and pulls up that particular wheel (and distributes its load elsewhere) while softer keeps that wheel on the road for longer. If I'm not misinterpreting what I've read, that is.

For example Twinz here (the above poster) and KONI (manufacturer of dampers) seem to be proponents of the former:

If my car has trouble turning-in on corner entry, I "soften" the rear shocks' rebound. If I feel like I have to wait forever for throttle out of turn or I'll kick the back end out, I soften the front shocks and the rear hooks up better on initial throttle.

If the car rolls on the rear outside suspension during corner exit, increase rebound damping force at the front inside. The front inside suspension affects the car mostly on corner exit. By adding rebound damping you will loosen the car up on corner exit. Source (http://www.koni.com/en-US/Cars/Technology/Over-Under-Steer/)

Then Jussi Karjalainen and Speed News sound like they state the latter:

A greater rebound setting will resist against the rear springs decompressing. If the spring is not allowed to rebound quickly, the rear tires will be somewhat lifted off the ground (exaggerated of course). Softer rebound settings in the rear will allow the rear tires to stay connected with the road and offer more rear-grip during that weight transfer to the front.

During the braking-to-cornering transition, the strong rebound damping will act to reduce the vertical load on the inside front tire while the dampers are moving. The inside front damper tries to lift its tire off of the ground. That load has to go somewhere, so it is distributed among the other three tires. Source (https://nasaspeed.news/tech/suspension/damper-tuning/)

So I'm trying to decide which it is...

Zeratall
21-06-2019, 08:02
So I'm trying to decide which it is...


You've noticed all the mis-information out there which is a huge leap compared to most sim racers. That being said all major textbooks on vehicle dynamics including RCVD state the effect of rebound is the later of the two so what jussi and speed news are saying is correct.