Suspension Theroies R-Us

[Jack Napier]

Yellowbird Tunes and drives like a Porche in GT6 (finally) still plagued by horrible tire/temp/grip dynamics in GT making her a bit tough at times, but in the end just another car in GT. Gotta have some skillz to handle her maxed out as does a real 80's Porche 911. Stock power is still more then a normal 911 but a much more friendly beast then maxed out.

I run her lap after lap inside tenths, 1:25 easy at Brands on RM maxed out just over 600pp.

Video before tune coming as I slaughterred the Aventador n unless people actually try it they wont know how good it drives So i think a video showing what it can do and how it goes where you pointed is needed..... The Ruf will only have TT and Race vids posted before the Tune. I have fun on the 600pp RH races with her, and decent times with her too.

 

[dtimefeel]

I'll give testing a shot.

Fairlady Z(Z34)'08 on The Streets of Willow (only ABS - set at 3)

As is - No modifications

Best lap 1:22.245

Fully adjustable suspension on default settings

Best lap 1:21:884

Using my FR wizard entering the default ride height (105).

1:20.589 <- this is using the "medium springs" option which gives a "sprung" condition to the front and rear

Where do you go from here? I found the front to be a little tight, but this is a point where changes become individual.

Please turn ABS off, its resistive force against nosedive makes it hard to diagnose braking oversteer...
What handling problems do you diagnose on the Z34 on default, customizable-default, and wizard-medium?

The point of contention for the first two pages of this thread was about which direction extension dampers does what.
I will run similar tests tonight..

 

[Motor City Hami]

I think we need to do just as you said. Try to agree on a few different cars, pp, drivetrain layouts. If the tuner wants to prove a point then this is the means. It's the only next logical step it seems. And it will be interesting. We might come up with near identical lap times with different tunes. But we will never really know unless we try.

We already have these. There is a FITT Muscle Car Tuner Challenge posted right now. The deadline is this Sunday. This is the best chance on GTPlanet to build a car within a set of rules on your tuning theory and put it up against the best (meaning Praiano). I have heard some say that they don't tune for offline, like it is beneath them. Well, if you your tuning theory works for online, you should be talented enough to build a tune for offline using the same theories to produce lap time results.

This muscle car group is proving to be quite challenging.

 

[donpost]

Did some testing:

The car was the RX7 Type S '03. Testing was performed offline. Only tuning performed was to add the adjustable suspension.

My first intention was to look at adjusting dampers for balance. I went to Autumn Ring full. I drove a few laps with the dampers set to default (3/3/3/3). I then focused on a certain section of the track:

(the chicane area on the right). This portion of track is taken at more or less constant throttle - so the main weight transfer occurring was left-to-right and vice versa. According to theory, stiffening the rear dampers and softening the front (both in extension and compression) should increase oversteer when you add steering, and decrease oversteer when you take off steering. I changed the dampers to 1/5 compression F/R and 1/5 extension F/R.

The result: nothing that I could notice I didn't go on to test transitions involving braking because IMHO the decel setting on the diff is WAY more powerful for tuning that.


Next I wanted to look into tuning dampers for best bump absorption - maximising grip over bumpy ground. For this I took the car to Nurburgring GP full. This track is known for being bumpy. I focused on the Schumacher Esses (SE for short:

This can only just be taken flat out if you use Sports Hard tyres. I set the compression settings front and back to 1 and took the car for a drive. You can certainly feel the car wallowing about as nothing is absorbing the spring oscillations. Going through the SE is fine. I then set the compression to 10 front and back. This time you can feel the car hitting the bumps in the road a lot harder. However, going through the SE flat out was still easy, even though you could feel the car bumping along.

In conclusion - dampers 1 donpost 0 lol. I'm going back to my original position of waiting for an update that will bring us telemetry. It's not an easy job to find the correct damper settings. The lack of feedback compared to RL track driving makes it a herculean task. Unlike almost every other tuning setting, they don't seem to have a huge impact on the way the car drives, much less laptimes. I'd love for there to be a simple, set system for finding the right setting like there is for the accel setting on the diff for example. I think that would be the holy grail of GT tuning

This is where I bow out - I'll keep an eye on the discussion though. If anyone can find an instance where you can really notice the effect of dampers please please please write it out like I have above so we can replicate the conditions for ourselves!

 

[dtimefeel]

This is where I bow out - I'll keep an eye on the discussion though. If anyone can find an instance where you can really notice the effect of dampers please please please write it out like I have above so we can replicate the conditions for ourselves!

If you read earlier in the thread - grab an overpowered-engined car like the Zonda R. Put RH tyres on it. Turn all assists off.
Take the first two corners on Nordschleife.
The first corner, Nordkehre, can be taken early braking, all pedals off (120kph), turn... if your car doesn't have severe turn-in understeer.
The second corner can be taken flat out (140kph)... if your car doesn't have severe power oversteer.

By changing only the dampers I was able to change whether or not my car could take the first corner or second corner, or both.

My findings were as per my post:
Where the RH/SR/etc was tuned for turn-in understeer, a configuration like 3/3/3/3 was undrivable, C3/5 E1/3 made the problem worse. C3/5 E 5/3 gave me some compensation to get me through those corners. Details in the postscript.
Where the RH/SR/etc was tuned for turn-in oversteer, a configuration like 3/3/3/3 was undrivable, but C3/5 E1/3 gave me some compensation.

As I have challenged people in this thread six times already, this is a valid test if someone other than me would even try it...

Details for the first test where the RH/SR/etc were tuned for turn-in understeer.

Comp 3/5, Ext 1/3 = POWER OVERSTEEEEEEER (second corner spin at 60% throttle)
Comp 3/4, Ext 2/3 = POWER OVERSTEER (second corner spin at 90% throttle)
Comp 3/4, Ext 4/3 = Power oversteer (second corner spin when flat-out)
Comp 3/5, Ext 5/3 = Stable (second corner safely flat-out)

As a further note, my final tuning for turn-in oversteer-type tunes, is like C0/8 E1/9 or something extreme like that. 6'40" on Nordschleife with no assists and a spin-out, meaning I could ostensibly have hit 6'35" with this tune.

 

[donpost]

If you read earlier in the thread - grab an overpowered-engined car like the Zonda R. Put RH tyres on it.
Take the first two corners on Nordschleife.
The first corner, Nordkehre, can be taken early braking, all pedals off (120kph), turn... if your car doesn't have severe turn-in understeer.
The second corner can be taken flat out (140kph)... if your car doesn't have severe power oversteer.

By changing only the dampers I was able to change whether or not my car could take the first corner or second corner, or both.

My findings were as per my post:
Where the RH/SR/etc was tuned for turn-in understeer, a configuration like 3/3/3/3 was undrivable, C3/9 E1/3 made the problem worse. C3/9 E 9/3 gave me some compensation to get me through those corners. Details in the postscript.
Where the RH/SR/etc was tuned for turn-in oversteer, a configuration like 3/3/3/3 was undrivable, but C3/9 E1/3 gave me some compensation.

As I have challenged people in this thread six times already, this is a valid test if someone other than me would even try it...

Apologies I overlooked that - I will absolutely give this a go tomorrow and report back 👍

Can I just confirm that the tune is as in post #39, and that you are using no assists? Are you using a DS3 or a wheel? I want to be certain I'm replicating your experiences precisely.

 

[dtimefeel]

Apologies I overlooked that - I will absolutely give this a go tomorrow and report back 👍

Can I just confirm that the tune is as in post #39, and that you are using no assists? Are you using a DS3 or a wheel? I want to be certain I'm replicating your experiences precisely.

I confirm that the tune for Test #1 is as per post #39, all assists off, using a G27.

The tune for Tests #2 and #3 are as follows:
#2: No ballast, input stock Zonda R specs into Voodoovaj's Wizard: Goal height 90mm, Very Hard springs (normal hard isn't possible on the Zonda R I think)
#3: 93kg ballast @ -50, should give 50/50 distribution. Input these specs into Voodoovaj's Wizard: Goal height 90mm, Very Hard springs.

All assists off on Tests #2 and #3 but they are using a DS3.

 

[Jack Napier]

Holy Gebronie

Damps are tunned to spring rates BEFORE you tweak for gains on the Track. You will not get far before thats understood. Low damps on hard springs is a clear sighn of too much theory not enough practical knowledge

Once your damps are in tune with the spring rates you tweak for gains and things will make much more sence tweak vs track performance.

Tweaking damps ignoring they need be FIRST tuned to spring rates has you guys all confussed and going in circles

All tuning should be done with no assist including the ABS crutch

 

[Highlandor]

We already have these. There is a FITT Muscle Car Tuner Challenge posted right now. The deadline is this Sunday. This is the best chance on GTPlanet to build a car within a set of rules on your tuning theory and put it up against the best (meaning Praiano). I have heard some say that they don't tune for offline, like it is beneath them. Well, if you your tuning theory works for online, you should be talented enough to build a tune for offline using the same theories to produce lap time results.

This muscle car group is proving to be quite challenging.

Those 'tests' are about as far from valid as you can get... might aswell be submitting numbers from your lottery ticket as 'results'..

 

[Jack Napier]

It is entertaining though. Like watching people try to figure out a puzzle unaware you tossed 5 pieces. Lmfao

Its not hard, just stop ignoring the dude giving you probably the most valuable GT tuning basics....

 

[Motor City Hami]

Those 'tests' are about as far from valid as you can get... might aswell be submitting numbers from your lottery ticket as 'results'..

What are you talking about? Where else do you have multiple test drivers across all skill sets drive a set of cars built to the same PP levels/specs on the same track? I think it is the best current measuring stick on GT Planet. It is for sure the largest data output. I learn something in every one of the FITT Challenges, especially from test driving other's tunes.

I think you are afraid to see how your tunes do head to head against others?

 

[Highlandor]

What are you talking about? Where else do you have multiple test drivers across all skill sets drive a set of cars built to the same PP levels/specs on the same track? I think it is the best current measuring stick on GT Planet. It is for sure the largest data output. I learn something in every one of the FITT Challenges, especially from test driving other's tunes.

I think you are afraid to see how your tunes do head to head against others?

LOL - just like you're too scared to leave your comfort zone and only tune a handful of easy cars, the easy way (nice grippy tyre to power / weight - PP ratio, offline and ballast too!!)- despite your ego inflating page after page guide of how to tune...you're the worst example of someone who talks the talk but doesn't walk the walk on this sub forum

Maybe you should read up on ethics in testing and see for yourself what constitutes a valid test and results.

These tests involves different test subjects and the results are not verified or validated by anyone (how do people know if all laptimes submitted are laps done the same i.e following the OLR guidelines). Do all testers do the same amount of laps?

Anyone who knows about ethics in testing would dismiss this as any kind of valid test and results.

Anyway - like I said before, not here to fight, if you're not man enough to let bygones be bygones and all you want to do is carry on with bullying people with disabilities via your perpetual antagonist comments, that's fine, you do that.

I'm sure GTP and FITT really appreciate you showing everyone this 👍

Good luck with your 'tests'

end of/

 

[Motor City Hami]

Anyway - like I said before, not here to fight, if you're not man enough to let bygones be bygones and all you want to do is carry on with bullying people with disabilities via your perpetual antagonist comments, that's fine, you do that.

You really are a piece of work. You seem to have a chip on your shoulder against me and I am still not sure why.

Let me know when you are ready to man up and put a tune head to head against the best... Praiano.

 

[BlueShift]

the best... Praiano.

Everybody can do this...

Low PP car are not technical to tune tbh, and when I see twin plate clutch on all his 400-450pp car, I know there I can get 0.5 / 1s per lap on any car just with this.

On his high PP cars I also see problems of downforce.

- edit - I don't want to say low pp. I wanted to say unmaxed pp. Now a maxout 2CV is hard to tune because she hold too much power and gets lots of problem she don't have with more reasonable amounts of PP.

FITT chalenge is 90% made of cars I don't love. If I tune cars I don't love, I make bad tunes. I'm emotional

Just read the FITT rules, well mkay, if you can choose your car, maybe I'll do it. But two days for me is too little. I've got that double setup rally/racing Gordini to finish and post before...

 

[donpost]

What's with all the hating on tuning comps?!

Their a great way to hone your skills and they often challenge you to tune cars that you wouldn't normally go near. Plus it's good fun. If it's "too easy" then one should have no problem winning the competition.

Truely baffling...

 

[BlueShift]

What's with all the hating on tuning comps?!

I disagree since day 1 in GT5 about the fixed track and gearbox settings. The first tuning challenge we got was supposed to be on two tracks and no gearbox adjustements and I "lost" it because the gearbox rule changed between the 2 testing events because people obviously optimized their gearbox for the first track only and started whinning about it.

This + loosing my save the next month killed my interest in the game. I have now 33% of the time I could have to play the game now. I'm not sure to make it for this chalenge but we'll see anyway. I know a shortway.

 

[Motor City Hami]

I disagree since day 1 in GT5 about the fixed track and gearbox settings. The first tuning challenge we got was supposed to be on two tracks and no gearbox adjustements and I "lost" it because the gearbox rule changed between the 2 testing events because people obviously optimized their gearbox for the first track only and started whinning about it.

This + loosing my save the next month killed my interest in the game. I have now 33% of the time I could have to play the game now. I'm not sure to make it for this chalenge but we'll see anyway.

That was kind of a long time ago - three years ago? The competitions have gotten a bit more organized over that time and many of the GT5 members have moved on to other games. It is a pretty friendly group now.

 

[BlueShift]

I think I'll post a C3 '69 if I want to make it by the time it closes. I have to rebuild it from mine in GT5, it was good. But that mean I have no more than 4-8-12 hours to do this, depending of my week-end, that's quite short, very short (for me, 12h is good but not enough to change car-I've got to be @800km to feel confident about a tune). This or I take the same car he chose (or anyone chose) for a compairison point.

 

[Motor City Hami]

I think I'll post a C3 '69

The C3 '69 Convertible is a very competitive car on that list. Praiano tuned the Mustang Mach 1

 

[Boone]

Edit: Explained very well! Thank you.

 

[Jack Napier]

No im saying adjust the SR making them stiffer and adjust the damps to the spring rate first, TheN you tweak to find gains and things will make more sence

 

[BlueShift]

The C3 '69 Convertible is a very competitive car on that list. Praiano tuned the Mustang Mach 1

Yeah I just saw, it's on a second list. I'm searching another car now, I want to be in the pack

 

[Jack Napier]

Low PP, cars that dont really need much tuning out the box (or complex tuning) in large volume is quantity over quality. Non tuners like volume so they can run many cars, and most often they like them easy to drive not nessesarily the "best" set ups... Scarred of cars that require actual "Tuning" deeming them unstable or some other nonsence. Thats not impressive, but clearly it is just the way its going to be on a Public forum. Seems so many "Tuners" are trying to figure out all the tuning theories they read up on, and in doing so overlook the basics of setting up the suspention...

Tuning the suspention and tweaking settings for gains is NOT the same thing but that FACT is ignorred here.

Step 1 - tune the suspention

Step 2 - tweak for gains

If you skip step one and just start tweaking for gains your starting from a out of whack tune and tweaks will NOT make sence, hense all the banging heads in confusion.

First thing to Tuning is stiffen up the springs for track performance AND the tires you intend on running.

Inorder to do this you need to raise the damp settings as you stiffen the SR. Dont focus on damp tweaking at this point just get the SR in the area you like and keep the damps matched to them.

Next Adjust the ARB, usually start around the weight spit, more weight stiffer ARB you will tweak this later.

With SR Damps and ARB roughly set you move on to wheel angles. This is a point where you have to feel em out a bit get them in the general area that feels good going around the track.

At this point you test if you SR is too stiff or soft using the ARB. Stiffer SR calls for softer ARB, so you keep the same offset on the ARB but raise and lower them testing out if she feels better with super soft or super stiff ARB. Best results with soft ARB is a sign the SR is too stiff, if she feels better with high ARB its a sign the SR are too soft. At this point you raise or lower the SR (depending on if the ARB revealled them either too stiff or too soft) while doing the opposite to the ARB, if you raise the SR, lower the ARB, if you soften up the SR then raise the ARB. Goal being mid level ARB. However its important during this process you KEEP the damps adjusted to the SR, if you raise or lower the SR, do tge same to the damps.

Matching your damps to SR is easy. If your SR lands where a 6 would be on the Damp slider, adjust the ext to 6. You can also adjust the comp to 6 but I like to have it lower by a click or to comparred to ext so when tweaking I have room to go both ways with the comp instead of only being able to lower it.

Now Tweaking the settings for gains can be done and things will make sence.

If you stiffen up your SR and leave the Damps at 3/3 default setting, tweaking the damps at this point is useless, confusing and inconclusive.

When you read about adjusting damps for gains the writer assumes you starting from a suspention thats already been tuned for the car and those "gains" your looking for can be found. They are NOT talking about starting to tweak for gains from a cookie cutter suspention set up like the in game default settings, they assume if your reading steps on advanced tuning you should already have the BASICS down.

 

[BlueShift]

The C3 '69 Convertible is a very competitive car on that list. Praiano tuned the Mustang Mach 1

I tuned a Shelby GT350, for me, american classic muscle car is a Mustang, period. Setup is 90% done, have to tune the gearbox now.

I tried his tune, to be sure of what I'm proposing. His tune is easy to drive and is -2sec than mine on Laguna Seca... Because of the used car.

I have no time left to change for a car like he used and put a C3 aswell I think. I'll try the 350R tonigth and see if my setup translates, if I get better times I'll post it. The car I choosed got a lot of personality and is funny to drive, so maybe I'll aim for the driver choice

Used comp>ext then inverted the setup I found and I got better times with a lot less agile car... Had to redefine susp geometry to camber = 0 though.

Found a few things :
* camber works almost as intended with comp > ext but it's downsize effects are a lot lot more prononced than in GT5. Maybe GT5 had a problem there. For ext > comp, it seems to me you've still got positive camber in some way. Maybe that's related to susp deforming or something. The more your camber, the more you "cut" corner "sharper" in the corner entry phase. But you'll have much corner oversteer esp with rear camber. Front camber seems to be somehow ok. Somehow.
You really see a lot of difference between 0/0 camber, 0.5 / 0.5, 1.0/0.5, 2.0/1.0 camber in the first laguna seca wide hairpin. Great curve to check corner entry btw.

* Damper : I think the gaps and the level are the more important base there. It really depends of how you want her to be driven, and the track you're in : on Roma I'm faster with comp>ext, on Laguna Seca, I'm faster with ext>comp. Strange ????

* RH comp>ext and RH ext>comp. It sligthly seems that effects of raising only one RH are inverted if you goes from comp>ext to ext>comp.

Most important discovery :
* Gas : I used a balanced setup by weigth curb, as usual. I had a lot of problems until I tried to put the gaz in the car. GoogleFu : the Shelby 350 got a 61 liters reserve, gaz is 0,755kg/l. That made 46kg in the rear, making my weigth distrib go from 54:46 to 53:47 when placed between like 15% to 33%.
Used 53:47 and MAGIC all my problems were gone.

=> the weigth ratio doesn't take into account gaz weigth.

Note for myself : the GT350R got 97.16kg of gaz.

 

[BlueShift]

Re-wrote S.Q.A.T., almost done. That'll save me a lot of time... No aero yet.

 

[Jack Napier]

Re-wrote S.Q.A.T.

 

[BlueShift]

It's not ready, full of bugs, and I doesn't have a clue on how US units works in the game.

If somebody would tell me, I'll do this monday maybe... It's not an auto-tuning tool, it's more calculation help because I was fed up with doing all that stuff with a pen and a calculator.

I can't play Monday -> Saturday in the day due to, well, family politics let's say. But I can program

 

[donpost]

Hey Blue if you can program maybe you can make some use of this excel model (attached)? It models the movement of the car in pitch and ride in response to different inputs. My programming is usually just a bug waiting to happen!

I don't know how useful it is - but it can show us some patterns. For example, here is the effect on force between tyre and road of taking a car and having it brake with a constant force of 10,000N.

Stiff springs and dampers:

Soft springs and dampers:

We see that as expected, soft or stiff the total amount of weight transferred is the same (once the suspension has settled). Stiff springs/dampers settle down faster than soft ones - again as expected. We also see that the force builds up quicker with the stiff setup meaning you can brake more aggressively with stiff springs.

Actually that probably doesn't tell us anything we didn't already know, but I love graphs so there

 

[xiando]

Holy Gebronie

All tuning should be done with no assist including the ABS crutch

Erm... why? ABS should only affect brake bias. I haven't seen any change in my cars' handling by enabling or disabling ABS. ABS (for me) is simply a modifier for the brake bias, and it allows me to "tune" the bias with more effective resolution than by going "prairie wagon" on the brakes and acting as if I lived in the 1960s instead of 2014.

 

[BlueShift]

Hey Blue if you can program maybe you can make some use of this excel model (attached)?

The only problem I see is there's a lot of input that we can't know via the game : tires coefficients, etc. I suppose track humidity and temperature of the road and tires plays a role... That's complicated, I don't know that's usefull or not.
I'm thinking about a more complete gearbox tab, but I'm not sure yet. Was reading aero article this afternoon, to see if it's possible to extract some things too.

US guys who play GT6 with US units, what are the units used by the game ?
Weigth in kg or lbs ? Spring in kgf/mm or in lbsf/mm ?

Could you post any screenshot from the suspension screen ?