Observations on suspension settings

[Stotty]

I have mine at -10 -10 as I found the rear became too unstable if I raised the front.

Getting the best out of the Caterham is more about learning the necessary techniques IMO (very smooth turn in, avoiding kerbs and precise throttle control)... most cars you can tame with tuning, but some will always just be nasty little 'things' whatever you do to them!

 

[CyKosis1973]

If you're running at -10 / -10 and I'm running at -5 / -5, I'll drop the rear by 2mm increments and see what happens...

{Cy}

 

[Paulie]

When I was testing my Monaro the other day the ride height adjustments had real world implications to the handling, I fail to see what all the hoop-lah is about.

 

[chuyler1]

I think people just expect a raked stance (low front, high rear) to provide downforce and grip in the front. However there is no aerodynamics modeling in the game to make that assumption true. Instead, the front suspension reaches the bump stops quicker and it causes understeer.

 

[Johnnypenso]

If you're running at -10 / -10 and I'm running at -5 / -5, I'll drop the rear by 2mm increments and see what happens...

{Cy}

Seeing as how the Caterham already has oversteer at level ride height, all this is going to do is induce more oversteer. Try it and see what happens.

 

[Johnnypenso]

Suspension bottoming out doesn't explain all the affects. If you have a balanced car at 0/0 or 10/10 ride height, then making it 10/0 or 20/10 should not create a tendency towards oversteer but rather the opposite, and yet that is what happens.

 

[CyKosis1973]

Seeing as how the Caterham already has oversteer at level ride height, all this is going to do is induce more oversteer. Try it and see what happens.

I'd agree, if everything was as it seems. However, if there is some irregularity with ride height then lowering the rear will induce understeer. The aim is to find what happens, (un)expected or otherwise, when I lift or drop the rear of the car...

{Cy}

PS - If I do find anything of note, I'll post it all here.

 

[Adrenaline]

Suspension bottoming out doesn't explain all the affects. If you have a balanced car at 0/0 or 10/10 ride height, then making it 10/0 or 20/10 should not create a tendency towards oversteer but rather the opposite, and yet that is what happens.

Are we still talking about FF? If not, what makes you think this?

I'm with Paulie. I think the Max/Min is the exception to the rule, that exploits something else in the physics, that has nothing to do with the potential reversed ride heights.

 

[Johnnypenso]

I don't test for bottoming out, but I am assuming that when I take a street car, trick out the suspension, it comes stock at say 6.0/5.0 F/R springs (or any combination of fairly low settings), 0/0 ride height and take it to 12.0/10.0 and 0/0 ride height, it should not be bottoming out at either end. If it does, then there's a whole other issue there and another thread...lol. But assuming it doesn't bottom out and the suspension is acting as it should, then raising the front ride height should make the car understeer by all that is holy in car tuning and according to GT5 itself. The opposite is true, in the few cars I've tested. Stiffen the springs from stock, add positive ride height to the front and keep the rear at zero, and cars tend to oversteer. Not the same for every car, not the same quantitative effect for every car, but the tendency is the same. My Xanavi GTR for example, is something like +9/+1 and handles like a dream now.

Perhaps my initial assumption is wrong, and GT5 suspension settings are so far off, that with stock setting of suspension, most cars are bottoming out, and even doubling spring rates they will still bottom out, which would be silly of course, but entirely possible in this game. In that case, you could explain the suspension settings from a bottoming out perspective only.

 

[CyKosis1973]

Seeing as how the Caterham already has oversteer at level ride height, all this is going to do is induce more oversteer. Try it and see what happens.

I settled on -8 / 0 ride height, what a complete revelation this car is with the nose on the deck and the tail in the air. I can't give full suspension specs as I've left my laptop power supply at work, and I've got about 30mins of battery left, according to Microsoft. Make of that what you will.

Anyway, my starting point for ride height was -5 / -5, I decreased the front and increased the rear by increments. With each increment the handling improved. I'll post the rest of the suspension as soon as I can, for critique. Let’s not forget I may well have done something completely crazy.

I 🤬 you not, I can drive this car hard and fast, straight out of the blocks, on cold S3 tyres and carve as quick laps as I can after 8-10 laps of tyre warming. Staggering.

Need a 50 lap S3 build; this could be your car...

{Cy}

 

[Basilea]

Hmmm today I tested with the Dodge Challenger R/T 70 RM and something is weird! I can't say what but it is... Ride Height is correct, at least visually! But the dampers and spring rates... a 15.0 on spring rate means it is stiffer than 3.0, the spring needs more force/weight to be compressed, no? And 10 for dampers means it takes longer to compress or extend, no? So the most movement you should get with low settings on everything?

ride height: +50/+50 (most suspension travel)
spring rate: 3.0/3.0 (should be very loose)
dampers ext: 1/1 (fast extension)
dampers com: 1/1 (fast compression)
anti roll: 1/1 (independent left and right)

then I just changed one to max value and it didn't do what is should!
dampers com: 10/10 and it felt like the compression was a lot more noticeable? But isn't that wrong? I might test more on this...

But now I just read some things about GT4! The official tuning guide from PD! And I start to believe that PD mixed something up when they changed the whole tuning settings for GT5... in GT5 it says you should have dampers extension higher than compression! And in GT4 it says the exact opposite! Same with toe in and out... Powerful RWD should have toe out on the rear and toe in on the front (GT4), but in game menu of GT5 says FH cars are better off with toe in...

Google Books (GT4 official tuning guide)

Please PD help us to see through all of it!

 

[Johnnypenso]

I settled on -8 / 0 ride height, what a complete revelation this car is with the nose on the deck and the tail in the air. I can't give full suspension specs as I've left my laptop power supply at work, and I've got about 30mins of battery left, according to Microsoft. Make of that what you will.

{Cy}

I'll be happy to test out your tune. I haven't put a lot of time into this car because it's hard to find anywhere to race it. I also have a tune from Stotty to try out as well. If we assume that higher front ride height increases oversteer, it follows that lower front ride height reduces oversteer so your -8/0 settings would make sense for this car.

 

[Sail IC]

Do you find any differences in the handling by running both ends high or low, ie lets say 10/10 or -15/-15. I understand that it looks different when looking at the replay and what the difference should be, but I don't experience it when driving. It feels the same to me and lap times are the same.

What I usually do is to first raise the car to max high and then I lower the front or rear to improve the balance of the car.

 

[Sail IC]

I find tuning cars for races and championships very interesting but I'm really frustrated by GT5 and here is why.

There are a few powertunes and in my opinion they are; Aero, LSD, Ridehight (front/rear difference), Rear toe, Brake balance, and Gearbox. I work a lot with them.

All the other tunes has such a small impact and its confusing if they are reverse or not. I usually just put in some common sense numbers, forget about it, and focus on the power tunes.

This is what I do but I don't like it. My tuning is for GT500 championships under PP regulations.

 

[KoAStR]

But now I just read some things about GT4! The official tuning guide from PD! And I start to believe that PD mixed something up when they changed the whole tuning settings for GT5... in GT5 it says you should have dampers extension higher than compression! And in GT4 it says the exact opposite! Same with toe in and out... Powerful RWD should have toe out on the rear and toe in on the front (GT4), but in game menu of GT5 says FH cars are better off with toe in...

Google Books (GT4 official tuning guide)

Please PD help us to see through all of it!

Yea I also noticed some of the GT5 in-game tuning menu descriptions for suspension settings, in terms of their effect on the cars handling, are the opposite from the description given in PD's guide that came out with the GT5 collectors edition.....Until I saw this thread I figured it was just a typo in one or the other, but it seems perhaps there some genuine confusion at PD!

I've never worried about it too much because I just tune the car based on feel anyway, not based on how I expect it to respond to tuning.

 

[CyKosis1973]

I'll be happy to test out your tune. I haven't put a lot of time into this car because it's hard to find anywhere to race it. I also have a tune from Stotty to try out as well. If we assume that higher front ride height increases oversteer, it follows that lower front ride height reduces oversteer so your -8/0 settings would make sense for this car.

In my exuberance I failed to take into account one small thing. My diff settings. The last time I drove the car, I was obviously experimenting with it, and had some wacky figures. So I'm going to have to go back and try it with slight more reasonable settings, as 60 Accel is going to have a large impact on understeer 🤬 🤬 I'm annoyed.

Anyway, I stand by the car as it is, because it's so incredibly different to how it drives straight outta the box. Here's where I am with the car so far. I've done very little to it. No weight has been taken out (hardly needs it), I've stiffened the chassis, oiled it, rebuilt the engine and straightened the chassis. Custom gearbox, custom springs, S3 tyres, prop shaft and that's about it (possibly changed the clutch, don't tend to bother with fly-wheels).

INITIAL R: 5
ACCEL R: 60 - I'd want to hack this figure in half, depending on how the car responds
BRAKE R: 5
RH F: -8
RH R: 0
SR F: 6.7
SR R: 5.4
EXT F: 2
EXT R: 1
COMP F: 2
COMP R: 1
ROLL BAR F: 3
ROLL BAR R: 1
CAMBER F: 2.0
CAMBER R: 2.6
TOE F: 0.12
TOE R: 0.19
BRAKE F: 6
BRAKE R: 4


{Cy}

 

[chuyler1]

I did some online racing last night on comfort soft tires (450pp restriction). I usually race on sport soft tires so I wasn't really prepared for the evening. I just wanted to share my results...

At one point I pulled out a '97 Toyota MR2. The tune was garbage because I last used the car on racing tires. I reset everything to default and removed the LSD. The track was Suzuka. Right out of the pits it was obvious this car had major oversteer issues. I carried what I thought was appropriate speed on cold tires and the back end came flying out mid corner as the front tires barely warmed up. It wasn't even worth finishing the lap.

First attempt at tuning...
Ride Height: -5 / +5
Camber: 0.5 / 0.5

Wow! What a difference! Now the car was understeering like crazy.

Second attempt:
Ride Height: -3 / +3

Ah hah! Much better balance. A little oversteer came back but I could put the nose where I wanted it. The LSD needed to go back on but I was out of time. I ran the race with those settings. Starting from last place (never got the full 2 laps in to qualify) I worked up to 4th over 5 laps.

So anyway, I have never made a change to spring rates, rollbars, or camber that gave me such instantaneous results. I'd consider this one of the first things tuners should look at when trying to get better balance on a car.

 

[CyKosis1973]

So anyway, I have never made a change to spring rates, rollbars, or camber that gave me such instantaneous results. I'd consider this one of the first things tuners should look at when trying to get better balance on a car.

Same here, small adjustments can have a big effect. Can't help thinking that I'd sort the rest of the suspension first though, and then use ride height to trim the car off...

{Cy}

 

[Motor City Hami]

So anyway, I have never made a change to spring rates, rollbars, or camber that gave me such instantaneous results. I'd consider this one of the first things tuners should look at when trying to get better balance on a car.

Makes sense, without the LSD. The LSD has a huge effect on handling. I think the biggest effect of all available adjustments. Just my opinion.

 

[chuyler1]

Makes sense, without the LSD. The LSD has a huge effect on handling. I think the biggest effect of all available adjustments. Just my opinion.

I'm on the fence about that. I read one of the threads talking about how almost all oversteer/understeer can be adjusted with the LSD. If I had time that night, I might have tried just installing the LSD and messing with it...but my problem was mid corner tail slip. Not sure how the LSD would resolve that since it is more prominent during acceleration and braking. I did have inside wheel slip exiting the turn, and I knew the LSD would resolve that...but with only 450pp it was manageable for the race with a little throttle modulation.

 

[f_399]

at least on the gt5 settings, from what i have noticed:



front down, rear up - better launch traction, lower mph

front up, rear down - less traction at launch, higher mph



in real life physics, does that make sense or is it truly inverted in gt5?

 

[Johnnypenso]

Makes sense, without the LSD. The LSD has a huge effect on handling. I think the biggest effect of all available adjustments. Just my opinion.

I must be missing something in tuning because I find that on most cars, the LSD is tuned to avoid it affecting handling in a negative way. Too much Accel and you're lighting it up under full throttle in the lower gears. I've never found any acceleration or handling benefit to have it any higher than just high enough to stop the inside wheel spinning. Too much Decel and it won't turn in as quick. As a result, 10/15/10 is my usual starting point and a lot of cars stay right there, and the rest are awfully close.

 

[KoAStR]

I must be missing something in tuning because I find that on most cars, the LSD is tuned to avoid it affecting handling in a negative way. Too much Accel and you're lighting it up under full throttle in the lower gears. I've never found any acceleration or handling benefit to have it any higher than just high enough to stop the inside wheel spinning. Too much Decel and it won't turn in as quick. As a result, 10/15/10 is my usual starting point and a lot of cars stay right there, and the rest are awfully close.

Agreed. Except I tend to use closer to 7/25/10 as typical.
The slightly higher accel value combats understeer during high speed sweepers by 'pushing' the nose around.
The lower initial torque value offsets this higher accel value to reduce 'twitchy' throttle response and combat low speed throttle oversteer.
Though nearly everything in diff and suspension (and downforce to some extent) tuning is a trade-off balancing act.

Certainly your decel setting has a big effect on the cars handling but should generally be quite low unless your car is very unstable during heavy braking and corner entry, otherwise you will induce understeer.

Occasionally I'll turn accel and/or inital torque up for a drift car to improve throttle response (especially in lower power cars) but lower is more predictable and controlable in most cases.

 

[kitesurfer]

i came across this thread yesterday and read through it all, so last night i thought i would give it a go.

the last time trial - autumn ring mini reversed i used the cappuccino i put in a time of 46.2 and placed 33rd, my best result yet, so i messed about with the spring hight to see how it would go, my spring settings were F -8 / R -7 =46.2 then changed to F -8 / R +50 and wasnt so keen on the way the car handled, then adjusted the rear spring to +30 and put in a time 45.6. i could have gone quicker, i still think +30 was too much but never made any more adjustments...

yeah so this does work but i think the cars have a sweet spot you just need to find what works for you...

gonna try it out more over the weekend and sort out the handling issues i have on other cars and see what happens...

 

[dr_slump]

the last time trial - autumn ring mini reversed i used the cappuccino i put in a time of 46.2 and placed 33rd, my best result yet, so i messed about with the spring hight to see how it would go, my spring settings were F -8 / R -7 =46.2 then changed to F -8 / R +50 and wasnt so keen on the way the car handled, then adjusted the rear spring to +30 and put in a time 45.6. i could have gone quicker, i still think +30 was too much but never made any more adjustments.

Spring rates? I think you mean ride height.
And you set the rear higher than the front, but what we are talking about in this thread is the reverse: lower rear than front ride height.

 

[kitesurfer]

Spring rates? I think you mean ride height.
And you set the rear higher than the front, but what we are talking about in this thread is the reverse: lower rear than front ride height.

yeah i wrote spring height, i meant ride height...

i thought what this thread was about was the thought of the suspension settings were reversed? so the front settings is the rear settings and vice versa?? i guess ive read wrong

 

[dr_slump]

yeah i wrote spring height, i meant ride height...

i thought what this thread was about was the thought of the suspension settings were reversed? so the front settings is the rear settings and vice versa?? i guess ive read wrong

Just the physic seems to be wrong, not the tuning menu.

 

[Drewsifer3x]

What if different versions of the game have different issues? Been reading through here and seeing completely different reports as to what works and doesn't. To be honest gt5 tuning has me fairly flustered....

 

[nomis3613]

What if different versions of the game have different issues? Been reading through here and seeing completely different reports as to what works and doesn't. To be honest gt5 tuning has me fairly flustered....

Possibly, but PD have never mentioned changes like this in their updates. It would be highly dodgy if they were messing with handling/tuning effects and sneaking it into updates without telling anyone. But then they were quite coy about the whole museum vs save file bug so I guess it's possible.

More likely IMHO is that people have different interpretation of what they experience when they drive the settings.

-----------------

In other news, I suspect that the effect is also related to whether the chassis is refreshed or old. I just had a car go from "better with-nose up tune" to "better without nose-up tune" after a chassis refresh.

 

[No_OBsT33R]

More likely IMHO is that people have different interpretation of what they experience when they drive the settings.

-----------------

In other news, I suspect that the effect is also related to whether the chassis is refreshed or old. I just had a car go from "better with-nose up tune" to "better without nose-up tune" after a chassis rebuild

I think you hit the nail on the head.