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TheGoodLife
19-10-2017, 00:44
What are some general recommended tweaks you can make to nearly every car to get better handling, particularly adjustments that would remedy understeer? For example: lowering/increasing tire pressure by “x”, increasing “y” to “z” value, etc. I’d appreciate some input. Thank you in advance.

Schnizz58
19-10-2017, 01:41
I don't know that there are any general recommendations. It depends on what aspect of the car's handling you want to improve. Typically for understeering, you want to soften the front suspension to make it more compliant. So reduce slow bump dampers in the front and maybe reduce the spring rate too. But be aware this will also make the car less responsive in places like chicanes and esses where you have to make quick steering inputs. Everything's a tradeoff.

TheGoodLife
19-10-2017, 23:39
Thanks Schnizz58! I actually came across the iRacing Setup Guide and it’s helped me out quite a bit. I think everyone should give it a read and keep in their arsenal to reference every now and again.

Jussi Karjalainen
20-10-2017, 00:56
For oversteer the most common adjustments are:

Softer front springs
Softer front anti-roll bars
Stiffer rear springs
Stiffer rear anti-roll bars

Also when looking at the power delivery, you can get big changes with the differential:

Lower power ramp angle tends towards more power oversteer
Higher coast ramp angle tends towards more lift-off oversteer

EDIT: Some seem to think that I meant those settings are "fixes" for oversteer. The original question was about overcoming understeer, so I answered "for getting more oversteer". Should probably have been a bit clearer.

Krus Control
20-10-2017, 01:32
If you want to get into the details dampers are a good way to dial stuff in. I've been meaning to do a little write up to share some of my experience.

Generally speaking there are some trends with dampers that aren't 100% rules but can move you along with setups.

For pre-apex oversteer/understeer in low downforce/slow speed corners or in banked corners use slow bump dampers to dial in a result. For instance if you have pre-apex understeer lower the value of the front slow bump damper to a softer value.

For post-apex oversteer/understeer in low downforce/slow speed corners or coming over crests use slow rebound dampers to dial in a result. For instance if you have post-apex oversteer lower the value of the rear slow rebound dampers to a softer value.

Fast dampers are a lot more complicated and there is no simple rule for getting them right. Basically they affect balance in high speed/high downforce corners. The Maggotts Becketts section of Silverstone is a good example of this type of comer. The goal with fast dampers is to dial in the stance of the car in corners like this.

Transition dampers I have almost no experience with, as the first time I was able to fiddle with this setting was in PCARS 2. But I have a handle on at least the transition bump dampers. They affect how long a car will naturally hold a slide. For instance, if you get oversteer in a corner and hold it through the exit then it will try to carry a wider radius and wont snap or shift out of the slide for a longer period of time if the rear transition bump damper has a higher value.

As for the transition rebound dampers I haven't figured them out yet at all.

Alan Dallas
20-10-2017, 02:52
The only advice I have was given to me decades ago by an old guy that was old hat at tuning suspensions(mostly for circle tracks and off road but it holds true to tarmac racing as well).
Here's a rough quote of what he told me in reguards to over/under steer, "Ride height and rake, if this is not setup correctly, you will never, ever, compensate with damper or shock adjustments.”

His point being, dial in under/over steer using ride height first. Get it as close to perfect for the car as you can, then you can fine tune it further with pre-load stiffness and lastly damper rates.
Been tuning suspensions in this order for eons now.
1) Ride height/rake
2) Pre-load(spring rate)
3) Damper rates

hkraft300
20-10-2017, 06:09
...

As for the transition rebound dampers I haven't figured them out yet at all.

Transition is the point at which the dampers switch from slow to fast. Can completely change your damper behaviour.

Check out Jussi's calculator to see how the numbers and damper graph move about when adjusting the transition.

LPlates
20-10-2017, 10:42
Did you mean understeer here?

My understanding from previous games (I'm certainly no expert) is that the settings you've advised here would make the weight of the car settle more on the front. Giving more front end grip.

Happy to be wrong but I'd like to understand the theory here.

Jussi Karjalainen
20-10-2017, 11:16
For oversteer the most common adjustments are:

Softer front springs
Softer front anti-roll bars
Stiffer rear springs
Stiffer rear anti-roll bars

Also when looking at the power delivery, you can get big changes with the differential:

Lower power ramp angle tends towards more power oversteer
Higher coast ramp angle tends towards more lift-off oversteerSome seem to think that I meant those settings are "fixes" for oversteer. The original question was about overcoming understeer, so I answered "for getting more oversteer". Should probably have been a bit clearer.

LPlates
20-10-2017, 11:34
Ah thanks for clarifying. Suddenly had a horrible feeling I'd been doing it all backwards :)

hkraft300
20-10-2017, 13:28
Some seem to think that I meant those settings are "fixes" for oversteer...

Could well be!
Something I'd learnt from you mate. Mistaking understeer as oversteer.

Jussi Karjalainen
20-10-2017, 15:15
Could well be!
Something I'd learnt from you mate. Mistaking understeer as oversteer.There is that actually, yeah. Thanks for bringing it up. =)

So there's a separate issue sometimes: You come into a corner too hot, try to turn, and the car just washes out. But you keep on piling the steering lock, and as the car slows down it then suddenly grabs on, and you end up spinning. For a lot of people what they take away from this is "the car oversteered and spun", when the reason they ran into the whole problem was the initial understeer.

Sometimes you can make a car less likely to spin out by making it more oversteery. For example if you're finding yourself having to use power oversteer to manage the car around corners, you might be inconsistent due to power oversteer being harder to control. Making the base setup more oversteery so that you can turn the car around without having to resort to power oversteer could well help you be more consistent and stable.

cpcdem
20-10-2017, 16:23
Similar thing with brake bias. Some cars have bias much to the front, so they do not turn easily under braking and you apply more steering trying to get the thing to turn! And when you stop braking, you end up with your wheels turned a lot more than needed..
I realized that my snap oversteer with some cars in exiting of slow corners after braking was mostly due to this after all.

VelvetTorpedo
20-10-2017, 18:12
Could well be!
Something I'd learnt from you mate. Mistaking understeer as oversteer.

Here's a fun video discussing that, for anyone who hasn't watched the SAFEisFAST series


https://www.youtube.com/watch?v=MfPgKnxJJ6I

Ball325
20-10-2017, 18:28
Another issue in online racing is people tend to think they need to brake later than they do. They don't think about the corner exit or what's after the corner. So they brake super late and get the car slowed down but their entry may be too late or too fast. So they either understeer through the mid point or get the car rotated too late and get back to the gas too late. Sadly this creates an environment of EVERYONE having to brake needlessly late in order to defend their position. I've been guilty of it too. I've found generally so far with people almost non-existent race craft I do not need to defend so aggressively. It's better to let them go and get a good exit. But this dynamic can cause a lot of handling issues to be misdiagnosed as people think they are racing with the people next to them and thinking they are on pace. No realizing they are hurting their lap times and over using their tires.

I've found in sims a lot of people think the answer to pace is in set up. Probably because it's so easy to tinker with. 90% of the time it is the driver that needs development. I try to make very minimal changes to a cars set up unless I know it is necessary, and the only way to know is do 10-15 laps (or more depending on your experience level) and when you aren't able to squeeze tenths of a second out of the car anymore and are focusing on hundredths and thousandths you will start to discover handling issues. You will say, ok, they car definitely has understeer. And then you will be able to say ok, it happens in fast corners or slow corners, On entry or exit. Then when you know this information you can start to think about tuning. This games tuning is complex and most people will do more harm than good.

Jussi Karjalainen
20-10-2017, 21:01
Yeah, another is sometimes forgetting how a gap that's 10-15 meters (2-3 car lengths) at 250 km/h turns into a 4 meter gap (less than a car length) at 80 km/h. Unless you brake a bit earlier than you normally would you're going to end up crashing in a situation like that.

And that's not even taking into account the loss of downforce when drafting.

jcook
21-10-2017, 09:46
great advice here - you can also adjust a diff for power off oversteer which can help corner entry a bit especially in vintage cars with no downforce , you can also gain a 'confidence lift' mid corner if you are understeering - simply make the ramp angle larger on coast than the power #