Jump to content
DIRT 5 - Chat about the game and get support here. Read more... ×
Christmas Period - Codemasters Staff and Support Read more... ×

Archived

This topic is now archived and is closed to further replies.

[DiRT 4] Constructive feedback on the subject of car-feel and physics: The Ultimate Thread

Recommended Posts

fab1701 said:
Hi all! New to the forums ;)

I tried tuning the Mk2 yesterday too and I think I managed to get some nice powersliding out of it, so I thought I post it here.

[some setup data]

Hope this helps, and feel free to correct if I'm wrong about something, because I'm not an expert ;).
I don't have much to add except to say thank you for posting actual numerical values, rather than saying "a few notches to the left" or whatever vague instructions I sometimes see. If the defaults do change, it's useful to have absolute values to go off.

I think I'll also have a look at how Dirt Rally setups are, and see how tuning the cars to the same values feels.

I also think it's important to point out that a "fully locked" rear diff is rarely actually fully locked – I think the Escort for example only goes up to 38%? It varies from car to car, and a bit depending on engineer skill too.

Share this post


Link to post
Share on other sites
One of the great problems of D4 is the ease of correcting the direction of the skid. With a strong turn of steering wheel you can control any type of situation. It's not realistic....

Share this post


Link to post
Share on other sites
Bert637 said:
One of the great problems of D4 is the ease of correcting the direction of the skid. With a strong turn of steering wheel you can control any type of situation. It's not realistic....
After some hooniganism with various cars around DirtFish, it sure seems as though both the lateral and longitudinal grip levels are unrealistically high. The cars can stop too fast, corner too hard and with too many of them, it's almost impossible to acheive wheel-spin from a dead stop. If it's not simply a matter of grip, perhaps it's a combination of other factors.

 Improved physics or not, D4 is feeling more and more like a Sim-cade title at best; that's fine if that's the end-goal but, if the Sim-players are truly what the developers are reaching for, they have some more work to do IMO. I don't think the handling is miles off, it would be sad to not see D4 get the rest of the way there.

Share this post


Link to post
Share on other sites
whats worrying is the amount of trolls and bad feedback that dirt 4 has gained.dirt rally put codemasters back on the good foot this seems that this could be putting it back in the bad place. :(


Share this post


Link to post
Share on other sites
Tried to copy the default Dirt Rally settings for the Mk2 over to DiRT 4. Completely different results. One oversteers excessively with endless front grip, while the other understeers excessively with endless rear grip.

Try it yourself

Share this post


Link to post
Share on other sites
I'm not sure about the grip levels beeing too high tbh. Not saying they're right either, but to me they look realistic for the most part and even more believable than DR's. The thing is, most of the rally-cars in D4 have rather open differentials in their default settings without any preloads, they lose power when trying to powerslide (weight is going to the outside wheel, inside wheel goes up and looses traction -> the diffs are giving most of the power to the inside and nothing happens except wheelspin). Same with the roll bars and suspension. Afaik these should be as soft as possible (without compromising stability), to give the wheels the best traction, but if they are too soft, it's very hard to overcome the lateral grip. These three: differentials, roll bars/suspension and the actual grip of the surface go hand in hand and one affects the other.

Subaru STI NR4 for example feels really good actually, even with it's default setting imo. That's one reason why I think the physics are mostly correct ;). But I see the problem with getting the cars to powerslide, especially RWDs, too. I don't know if it's realistic or not, but I feel that it is in fact really difficult to make them behave more oversteery and stable in slides at the same time. Maybe it's because what I'm doing is wrong, maybe it's the cars themselves idk.

But we have two of those three parameters I mentioned to play around with. I think it would be helpful to determine the best setup for each car and find the limits of what is actually possible with the tuning before taking a shot in the dark.


Regarding the DR Mk2 default settings: Well, thats really interesting that the results differ so much. Too bad that I already uninstalled DR :(. Seems the physics refinement got pretty deep after all...

Share this post


Link to post
Share on other sites
Slowish said:
Bert637 said:
One of the great problems of D4 is the ease of correcting the direction of the skid. With a strong turn of steering wheel you can control any type of situation. It's not realistic....
After some hooniganism with various cars around DirtFish, it sure seems as though both the lateral and longitudinal grip levels are unrealistically high.
The key word here is "seems". At the end of the day what it seems like to you is irrelevant. What matters is whether it's realistic or not.

But I suspect I'm wasting my time again. I mean after all, you've been told that the grip levels are realistic by a mechanical engineer with rally experience ( Headlong), you've been told by Paul Coleman himself, you've (presumably) seen a video of an old-ish rally car pulling g-forces approaching F1 levels into a square left on a loose surface, but none of that seems to be getting through. 

I think at this point some humility and at least some faint awareness of the limitations of one's knowledge wouldn't go amiss. 

Share this post


Link to post
Share on other sites

fab1701 said:
I'm not sure about the grip levels beeing too high tbh. Not saying they're right either, but to me they look realistic for the most part and even more believable than DR's. The thing is, most of the rally-cars in D4 have rather open differentials in their default settings without any preloads, they lose power when trying to powerslide (weight is going to the outside wheel, inside wheel goes up and looses traction -> the diffs are giving most of the power to the inside and nothing happens except wheelspin). Same with the roll bars and suspension. Afaik these should be as soft as possible (without compromising stability), to give the wheels the best traction, but if they are too soft, it's very hard to overcome the lateral grip. These three: differentials, roll bars/suspension and the actual grip of the surface go hand in hand and one affects the other.

Subaru STI NR4 for example feels really good actually, even with it's default setting imo. That's one reason why I think the physics are mostly correct ;). But I see the problem with getting the cars to powerslide, especially RWDs, too. I don't know if it's realistic or not, but I feel that it is in fact really difficult to make them behave more oversteery and stable in slides at the same time. Maybe it's because what I'm doing is wrong, maybe it's the cars themselves idk.

But we have two of those three parameters I mentioned to play around with. I think it would be helpful to determine the best setup for each car and find the limits of what is actually possible with the tuning before taking a shot in the dark.


Regarding the DR Mk2 default settings: Well, thats really interesting that the results differ so much. Too bad that I already uninstalled DR :(. Seems the physics refinement got pretty deep after all...

When reading your posts it's pretty apparent that your understanding of physics and car dynamics is way beyond what the great majority of the posters have demonstrated here. And you seem to think that the grip levels are more or less correct. Coincidence? I think not. 

It's also admirable that instead of whining you've actually embarked on a journey of discovery and experimentation to see how setup changes affect the car behaviour. I have done the same and have found that on the whole I'm able to do everything with the cars in D4 that rally drivers are able to do in real life, and that includes power sliding. 

Please keep posting your findings here, as there is always hope that even the most stubborn of the posters here will eventually see the light. 

Share this post


Link to post
Share on other sites
dgeesi0 said:
whats worrying is the amount of trolls and bad feedback that dirt 4 has gained.dirt rally put codemasters back on the good foot this seems that this could be putting it back in the bad place. :(


Seriously, people are making this out like the game is need for speed or something and it's sad to see the hard work they put in be put in jeopardy because of this type of back lash. Yes something is odd with the rear of the cars on gravel, it's still lots of fun and it's definitely not easy to push to the limit. I know I'm better at dirt rally still.

Share this post


Link to post
Share on other sites

fab1701 said:
Regarding the DR Mk2 default settings: Well, thats really interesting that the results differ so much. Too bad that I already uninstalled DR :(. Seems the physics refinement got pretty deep after all...

Don't worry about it. The cars in DR don't behave realistically enough for you to be able to draw any meaningful conclusions. 

Share this post


Link to post
Share on other sites
Heres a video of me locking the rear diff of the Mk2 and driving (very badly so please forgive me) around Dirtfish but you can see it understeering when I put the power down. Sometimes it does step out but you should be able to throttle control a slide around that donut area and it just doesn't want to. Let me know if I have done a setup wrong though...

https://www.youtube.com/watch?v=SJdJNz9QDOw
@SirPhilMcKraken have you driven the M3 in Spain?!?  Flip that thing over steers all day long!!  Haha, I wonder if the MK2 has a similar feel in Spain and that it's just gravel physics in general that require needs tweaking
General Thread Question here:  Can anyone explain the 'Flag' option on each thread post??  I got 'flagged' for my response to @SirPhilMcKraken (see above) and I'm wondering why??

Share this post


Link to post
Share on other sites
Heres a video of me locking the rear diff of the Mk2 and driving (very badly so please forgive me) around Dirtfish but you can see it understeering when I put the power down. Sometimes it does step out but you should be able to throttle control a slide around that donut area and it just doesn't want to. Let me know if I have done a setup wrong though...

https://www.youtube.com/watch?v=SJdJNz9QDOw
@SirPhilMcKraken have you driven the M3 in Spain?!?  Flip that thing over steers all day long!!  Haha, I wonder if the MK2 has a similar feel in Spain and that it's just gravel physics in general that require needs tweaking
General Thread Question here:  Can anyone explain the 'Flag' option on each thread post??  I got 'flagged' for my response to @SirPhilMcKraken (see above) and I'm wondering why??
Someone is being a child and flagging posts they disagree with.

It's usually for flagging spam.

Share this post


Link to post
Share on other sites
Heres a video of me locking the rear diff of the Mk2 and driving (very badly so please forgive me) around Dirtfish but you can see it understeering when I put the power down. Sometimes it does step out but you should be able to throttle control a slide around that donut area and it just doesn't want to. Let me know if I have done a setup wrong though...

https://www.youtube.com/watch?v=SJdJNz9QDOw
@SirPhilMcKraken have you driven the M3 in Spain?!?  Flip that thing over steers all day long!!  Haha, I wonder if the MK2 has a similar feel in Spain and that it's just gravel physics in general that require needs tweaking
General Thread Question here:  Can anyone explain the 'Flag' option on each thread post??  I got 'flagged' for my response to @SirPhilMcKraken (see above) and I'm wondering why??
That was me. I felt at the time that your comment about gravel needing tweaking was spammy since this was already mentioned to nauseating levels and never substantiated. Maybe I was wrong and I will be happy to unflag you. 

But tell me this: how come no-one has hit the "agree" or "like" buttons on my posts showing the video of the Audi Qauttro which shows that the grip levels in D4 are correct and which shows the irony of a poster who does not understand physics and car dynamics trying to educate a mechanical engineer with rally experience about physics and car dynamics. 

Why is it that my posts correctly explaining various aspects of car behaviour are automatically disagreed with, while nonsense posts spouting obviously incorrect information and explanations are automatically agreed with? 

How come that when a somebody posted all those videos of the escort in the Greek rally clearly showing the car behaving like a wallowing pig that bogs down all the time and which is driven very straigh through the stages, nobody asked why this disparity between this behaviour there and the behaviour of a similar car in other videos? 

I could go go on but I think you get the message. 

Share this post


Link to post
Share on other sites
Scyy said:
Heres a video of me locking the rear diff of the Mk2 and driving (very badly so please forgive me) around Dirtfish but you can see it understeering when I put the power down. Sometimes it does step out but you should be able to throttle control a slide around that donut area and it just doesn't want to. Let me know if I have done a setup wrong though...

https://www.youtube.com/watch?v=SJdJNz9QDOw
@SirPhilMcKraken have you driven the M3 in Spain?!?  Flip that thing over steers all day long!!  Haha, I wonder if the MK2 has a similar feel in Spain and that it's just gravel physics in general that require needs tweaking
General Thread Question here:  Can anyone explain the 'Flag' option on each thread post??  I got 'flagged' for my response to @SirPhilMcKraken (see above) and I'm wondering why??
Someone is being a child and flagging posts they disagree with.

It's usually for flagging spam.
Thanks @Scyy I thought as much :/

Share this post


Link to post
Share on other sites
@chukonu regarding matching tuning with Dirt Rally, isn't this Difficult to do with the suspension since Dirt Rally doesn't give numerical values for Suspension and roll bar stiffness, as well, in Dirt rally tuning for front and rear seems to be aligned so if you put both front and rear in the exact middle it's the same, where as Dirt4 the value range you can set for front and rear suspension is different.

Share this post


Link to post
Share on other sites
nbates66 said:
@chukonu regarding matching tuning with Dirt Rally, isn't this Difficult to do with the suspension since Dirt Rally doesn't give numerical values for Suspension and roll bar stiffness, as well, in Dirt rally tuning for front and rear seems to be aligned so if you put both front and rear in the exact middle it's the same, where as Dirt4 the value range you can set for front and rear suspension is different.
Plus suspension geometry is now much more accurately modelled as actual levers that not only influence the force feedback accordingly, but also how the car is affected by the driver inputs and the topography. 

Combine this with the fact that angular inertia is also much more realistically modelled, and the surfaces actually interact with the tyres properly, and the result is that very little of the suspension setups from DR will translate into D4, except perhaps in a very general way. 

My my advice would be to actually learn something about car dynamics and real life setups and apply those in D4. That's what I do and it works really well 90 percent of the time. Plus there is lots of info on how to set up racing cars on the internet for free. 

Share this post


Link to post
Share on other sites
In the meantime I'm working on a physics mod for Dirt Rally based on RFPE (but much better :smiley: and for all the cars).
First attempt for classic RWD on gravel:
https://youtu.be/P-31BE6OKM0
(spoiler: bad driving inside :dizzy: )
This shows exactly what people in genersl think of loose surfaces and RWD. 

"Hey, it's gravel and RWD, there must be close to zero grip!"

If the Fiat used standard everyday road tires, yes that is probably how it would behave, but it's on proper grooved competition tires. There is much more bite both lateral and longitudal than what you have in the video.
The default grip level of the RWD cars in DR is pretty great. If you want to improve DR there are other things to tweak.

Share this post


Link to post
Share on other sites
Heres a video of me locking the rear diff of the Mk2 and driving (very badly so please forgive me) around Dirtfish but you can see it understeering when I put the power down. Sometimes it does step out but you should be able to throttle control a slide around that donut area and it just doesn't want to. Let me know if I have done a setup wrong though...

https://www.youtube.com/watch?v=SJdJNz9QDOw
WOW, you have the setup SO wrong. What you have there would create understeer, lol.

Toe IN .4 not toe out, for better response. Full camber is way too much, try with around -1.5. You are causing the front wheels to lay over too far and loose contact with the surface. Anti-roll bars are the big thing though, really stiff at the rear, and soft at the front (not the way they work in RL but is gets the game right.) play with the settings to personalise but it will help. Try the below video for a guide, my Mk2 handles as well as DR now IMO. 

PS: not my video, but I was really happy to find it.

https://www.youtube.com/watch?v=vfXwdWlF22Y&t=278s

Share this post


Link to post
Share on other sites
Heres a video of me locking the rear diff of the Mk2 and driving (very badly so please forgive me) around Dirtfish but you can see it understeering when I put the power down. Sometimes it does step out but you should be able to throttle control a slide around that donut area and it just doesn't want to. Let me know if I have done a setup wrong though...

https://www.youtube.com/watch?v=SJdJNz9QDOw
WOW, you have the setup SO wrong. What you have there would create understeer, lol.

Toe IN .4 not toe out, for better response. Full camber is way too much, try with around -1.5. You are causing the front wheels to lay over too far and loose contact with the surface. Anti-roll bars are the big thing though, really stiff at the rear, and soft at the front (not the way they work in RL but is gets the game right.) play with the settings to personalise but it will help. Try the below video for a guide, my Mk2 handles as well as DR now IMO. 

PS: not my video, but I was really happy to find it.

https://www.youtube.com/watch?v=vfXwdWlF22Y&t=278s
Please explain why toe-in would give you better "response". And what do you mean when you say ARB's contradict how they work in real life?

Share this post


Link to post
Share on other sites
Heres a video of me locking the rear diff of the Mk2 and driving (very badly so please forgive me) around Dirtfish but you can see it understeering when I put the power down. Sometimes it does step out but you should be able to throttle control a slide around that donut area and it just doesn't want to. Let me know if I have done a setup wrong though...

https://www.youtube.com/watch?v=SJdJNz9QDOw
WOW, you have the setup SO wrong. What you have there would create understeer, lol.

Toe IN .4 not toe out, for better response. Full camber is way too much, try with around -1.5. You are causing the front wheels to lay over too far and loose contact with the surface. Anti-roll bars are the big thing though, really stiff at the rear, and soft at the front (not the way they work in RL but is gets the game right.) play with the settings to personalise but it will help. Try the below video for a guide, my Mk2 handles as well as DR now IMO. 

PS: not my video, but I was really happy to find it.

https://www.youtube.com/watch?v=vfXwdWlF22Y&t=278s
Yeah but I think currently the descriptions are wrong for the toe angles and are back to front. Anyway I will give that video a go and see how I get on :)

Share this post


Link to post
Share on other sites
bogani said:
In the meantime I'm working on a physics mod for Dirt Rally based on RFPE (but much better :smiley: and for all the cars).
First attempt for classic RWD on gravel:
https://youtu.be/P-31BE6OKM0
(spoiler: bad driving inside :dizzy: )
This shows exactly what people in genersl think of loose surfaces and RWD. 

"Hey, it's gravel and RWD, there must be close to zero grip!"

If the Fiat used standard everyday road tires, yes that is probably how it would behave, but it's on proper grooved competition tires. There is much more bite both lateral and longitudal than what you have in the video.
The default grip level of the RWD cars in DR is pretty great. If you want to improve DR there are other things to tweak.
https://youtu.be/ayEp0RmWMYs

...and this is on dry asphalt. 
The notes in Italian are hilarious :smile:

Share this post


Link to post
Share on other sites
Toe gives the wheels a tendency to turn. In the case of toe-in, the outside wheels want to go to the inside. When turning, the weight goes to the outside and the turnig then seems to be quicker, or more responsive in the process, thats how I understand it. I think negative camber has a similar effect, and can be countered by a bit of toe-out. The downside of this is, that toe also comes with instability, because the neutral direction the car wants to go then depends on the weight distribution. FWDs also come with a bit of toe-out, because under power the front wheels are forced to the front and then straighten out in the process ;).

Share this post


Link to post
Share on other sites
the thing is that video and getting it right still doesnt get the rwd cars doing it right.

just spent some time in escort mk2 on a few different events set some world records event flung the car more than it needed to to try and get those trademark escort backend magic.it just doesnt do it as you want.set up or no set up.


Share this post


Link to post
Share on other sites
fab1701 said:
Toe gives the wheels a tendency to turn. In the case of toe-in, the outside wheels want to go to the inside. When turning, the weight goes to the outside and the turnig then seems to be quicker, or more responsive in the process, thats how I understand it. I think negative camber has a similar effect, and can be countered by a bit of toe-out. The downside of this is, that toe also comes with instability, because the neutral direction the car wants to go then depends on the weight distribution. FWDs also come with a bit of toe-out, because under power the front wheels are forced to the front and then straighten out in the process ;).
Toe-in is not the recipe for better turn in response, toe-out is.

The description is the tuning menu is wrong, which they are aware of.

Share this post


Link to post
Share on other sites

×