Damping

[Fit4aking]

Feuer, I wouldn't count out your intellect just yet!

I've been following along with this as I struggle to balance over/under steer in a Toyota 2000GT.  I didn't have the motivation to attempt a rebuild of the car until last night and I kept this topic open the entire time I was setting up the car.  Adjusting the dampers in the way you suggest, f-dog, significantly improved the way the front end of the car tucked into both hairpins and mid speed sweepers.  Catalunya National to be precise.  One thing I noticed was that increasing the front rebound made the car feel a bit nose heavy.  I didn't change the bias at all but in trying to keep the rear from wandering I ended up with a car that "felt" like it was understeery when in fact I was able to make the car hold the inside line easier.  Another adjustment that greatly improved the transitional qualities of my narrow little screamer was increasing the rollbar stiffness by twice the value generated in your calc. I'm using an older version, Slave Munkys, but not as intended.  I input values until they match default settings closely and then use the biasing inputs, and stiffness multipliers, to fiddle with the car as needed.  Not exactly plug and play but I still feel like I'm tuning the car.

Each time I stumble upon a useful tool like this I feel the need to revisit each of my "pride and joy" tunes and have a redo so I'm thankful I don't have a slew of cars in my garage at the moment.  (I've only managed to put any time into 5 or 6 cars at the moment and make them right. I'm sucking at this version.)

Just wanted to say that this conversation between you and Spiny has been helpful, and your predictions were on the money for the sake of helping my tune without me even asking.  I will build out the Mazda as it looks like a decent car, unfortunately the FXX doesn't interest me much and I've already sold the gift version back to the game, I hate clutter in the shop.

[feuerdog]

In my calcs, I have tried to balance overall ARB strength with overall Spring strength.
The reason I mention this is that too much ARB is a "bad thing".
You have to let the car pitch and roll somewhat to allow the weight transfer to work for you. Having that weight load the side of the car where the work is being performed is a "good thing".
The issue in identifying "too much ARB" is that it is masked in other benefits,....but I still think the car will actually amplify its weaknesses at the same time. A well balanced/tuned car with too much ARB will actually handle quite well on smooth tracks and ovals, but suffer greatly when it hits the twisties.

As per my tuning standards, I prefer a more generic, "all-purpose" setup

So when you tell me youre doubling the values of the ARBs that raises a flag in my head. The only way I would personally run ARBs so stiff was if the springs were 50% softer.
I'm not saying you're wrong, i'm just sharing information.

My current tunes generally run ARBs between 36~40 accumulated value, and accumulated springs at approx 40% of total weight.

[Fit4aking]

Just to clerify my initial sway setting were in the 12 to 14 range so in doubling them I was closer to default the the extreme end of the spectrum.  The accumulated value is 54.3, a tick high, so I'll try to soften them by a percentage overall and retest.  I did soften the springs considerably, not sure if it was 40% but quite a bit in my opinion.

EDIT: The springs were inadvertantly, exactly 40% of total weight.

In testing I did find that the jump in sway stiffness had very positive results and was a direct change to increase transitional instability.  The car responded well so I think I was way soft initially with the sways.  This is still a WIP for me so anything I can do to sort it out will translate to success down the road.

[Spiny Anteater]

Feuer - I definitely wouldn't discount your dampng know-how. Last night I ran for a bit showing offline so that I could test various settings. All my original settings remained the same, but I adjusted the damping as below:

1) All settings as shown on p.1 - I've already mentioned how this ran, and the only purpose here really was to get a comparison time which is affected by my form last night - this was 1:08.9xx at Catalunya National (note all runs were in test drive so don't appear on the leaderboard)

2) Using Feuerdog's settings of 8.0/4.0F and 8.0/4.0R - Immediately this felt more planted under acceleration with just a slight whiff of a loss of traction accelerating through the last corner, yet had sacrificed almost nothing on turn in. This tune compared to Tune 1 pretty much confirms that a little knowledge can be a very dangerous thing. It felt really good to drive and this was confirmed by best lap of 1:08.1xx

3) 4.0/4.0F, 8.0/4.0 R - I wanted to feel for myself the effects of changing the front rebound, so went for extremely soft rebound at the front (same as front). Immediately the car felt twitchy, particularly in a straight line as if it was hunting for a rut in the track to follow. You could also feel the front end bobbing around as you got on the throttle but the rear end was very planted under acceleration. I absolutely hated driving this version, but the time was surprisingly not bad - 1:08.4xx

4) 12.0/4.0F, 8.0/4.0R - This was to test the effect of very high rebound values. The car only took one attempt to settle into its line, but did so in a very ponderous manner. It was however very stable once it had set for the corner. This version had the most trouble getting traction out of the corner of any of these four set-ups - 1:08.5xx

5) Back to tune 2 (FD damping) to see if my driving had been improving over the night. It had, but only by a tenth - 1:08.0xx

6) 7.9/4.0F, 8.0/4.0R I felt that this still wanted a tiny bit more traction so reduced the front rebound setting to 7.9 - a tiny change really but it did the trick in that the car felt like it had more traction under acceleration (that may have  been a confidence thing, I don't know). The time improved to 1:07.8xx, although I did have an uncertified 1:07.6xx

7) Tune 6 with reduced front aero - Surprisingly this seemed to affect the whole car, not just the front end and killed the lap time. Best with this was 1:08.8xx and that was half a second quicker than the next time. Not surprisingly I returned to full aero.

Tune 6 with double strength ARBs (21.0/17.2) - Unknownst to me, this ended up smack in the middle of FD's 36-40 accumulated ARB value. The car showed noticeably less roll, and felt marginally better to drive. At one stage I was on course for a 1:07.5 before missing an apex, but ended up with a best lap of 1:07.8xx. At this point, I decided I was satisfied with the tune and headed off to try Amalfi Reverse. After (quite) a few laps, I finally had a lap I could be satisfied with - 0:55.926. That was 1/100th second behind Daveyskills in a stock FXX, which might sound really rubbish. But... in FM2 I seemed to be the best part of a class behind his times on any given track. To be needing only 11PI to keep up was amazing for me.

I think it's fair to say that FD got the damping pretty much spot on which is incredible for a figure off the top of his head. Now, I'll give his tune a go around the two tracks (might not be tonight, but it will be within the next couple of days) and see how that compares. I suspect well.

I'm also glad that this thread is helping other people as well (Fit's not the first to say that) as to me it is tying in exactly with the meaning of this site. Although I've been the lucky recipient of feuerdog's direct advice, I know from taking on board his (and Blooze and others) replies to other people's questions that using the information directly is also incredibly benfeficial.

Finally a note to Fit - having got the FXX about where I want it I can now categorically state that I still have work to do on the Mazda. It feels more tail happy than the FXX, so I plan to try and apply FD's guidance in this thread to that car later in the week - I will report back when I have something on it.

[feuerdog]

I'm happy to have been any help. 

[Fit4aking]

Discussion of any type, well intellegent conversation, is always beneficial to any kind of community.  Everyone on here has helped in some form or another.  My learning curve for FM3 is kind of steep so every little bit has been a step forward.

Spiny - No matter what state of tune the Mazda is in I think I may build it out so I can compare apples to apples with your findings.  It's been a car on my list of things to do for a while and this is just another nudge to get it done instead of just plan on doing it.

Oh, one last thing.  I posted the changes to my little project on the daught net for the masses and the response was that the car in by far easier to drive than the last version.  Not a lot faster but easier to drive.  Its good to be able to put something out that everyone can use with results.

[pistolpig]

What a fantastic discussion. I truly enjoyed reading this.

Sometimes I understand concepts, but it takes reading them again to remember their significance.

Thanks to your very straight forward explanations, you have gotten me thinking about all of this properly again, FD. Just as you always have with suspension-related conversation.

[TheJohnNewton]

So far my accumulated tune time is about 15 min    as I'm finding the stock tunes are generally decent but I'll be using this thread once I get around to actually tuning.  Maybe this time I'll understand the effects of these settings with all you guy's help.

[Fit4aking]

TJN - If I could have a tune done in under an hour I'd be happy.  As it stands now most of my tunes take two to three hours to finalize and with that much seat time I normally find an issue that warrants a rebuild.  Rinse, and repeat. 

[TheJohnNewton]

Fit - Oh in FM2 I spent hours in the tune shop.  Generally I'd start with a Blooze tune or FD then trial and error it from there which is not an efficient use of time.  So there were hours in the shop.  In FM3 I've just been running through career not even adjusting the tire pressure for the most part.  I'm finding the stock tunes generally are very drivable.  I just jumped online for the first time a few nights ago with Hop and Open and few others and had to drive my mostly stockers.  I found that the Evora, which I had just bought that day, was pretty darn decent ride in stock form.  The Califonia was pretty good as well.  Once I build up my bank account, car inventory, via working through the career I'll get back into the tune shop.

[Spiny Anteater]

Fit - you might want to try this version - it's a bit easier to drive and that has made it a bit quicker. I've shown the changes in red - there aren't many but they have made a noticeable difference 

B500 RX-8:
Engine & Power - Sport Air Filter, Oil & Cooling, Race exhaust and Flywheel
Drivetrain, platform & handling - All parts upgraded to Race (incl roll cage & weight reduction)
Tyres: Race compound, stock width
Rims: Stock rims
Aero: Front & Rear bumper

Power: 319bhp
Torque: 210lb-ft
Weight: 2566lbs
Weight Bias: 52% front

Tyres: 27.0/27.5
FD: 5.30
1-6: 2.89, 2.04, 1.55, 1.27, 1.07, 0.89
Camber: -1.1/-0.9
Toe: 0/0
Caster: 5.0
ARBs: 24.40/23.60
Springs: 664.8/597.5
Ride height: 6.1/6.1
Rebound: 8.1/8.0
Bump: 3.9/3.9
Aero: 100/200 (max again - don't worry, not all my cars are like this!)
Brake balance: 47% front
Pressure: 100
Diff: 40% accel/25% decel

Like I said, small changes to the tune have made a noticeable impact on the feel of the car - try out both versions if you want to see for yourself.

As for me, I'm off to try FD's FXX 

[Fit4aking]

I'll definitely give it a shot Spiny.  It will do nicely next to the ..... um... no B-class cars I have at the moment.  Still working my way up from F and I'm not moving very fast.  D is next but I don't mind a quick excursion to the faster classes now and again.

When I applied these few adjustments to my Toyota I was shocked at how easy it was to fine tune with minor adjustments here and there. 

[Spiny Anteater]

Tried out FD's FXX last night. As a comparison run, my FXX ran 1:07.499 around Catlunya National the night before. After a bit of practice, I had a 1:07.566 in FD's so there is nothing to choose between them in terms of performance.

There is a bit in character though. FD's feels more stable and gets traction better than mine, but doesn't seem quite so good under brakes. Actually, to clarify, FD's feels more stable as you get the traction, but I couldn't get on the power quite as early as mine without going off the outside of the bend, so the extra traction didn't translate into less time. In fact it was about half a car length faster over the first half of the lap, but mine was better through the tight left hand hairpin and the following right hander and gained a couple of car lengths through there. I got an excellent run through the chicane in FD's which I hadn't got in mine and that put the cars level again, but mine was a tiny bit quicker through the last corner and that's where the final 1/20 second came from.

I would say that the difference in the two cars comes down to driver preference. In FM2 I generally preferred a slightly more oversteery set-up than I got from the tuning calculator, and I think this shows up again. Another driver may well be faster in FD's, and let's be honest, the difference for me was minute (57th place in mine, it would have been 59th with FD's). So, if anyone does decide to run one of these FXX's, I would suggest trying both out and see which one suits you.

[feuerdog]

Thanks Spiny, that just reinforces what i've said before. "Tune for feel. Build for performance."

I agree with you 100%.


I ran our FXX through some testing last night with my calcs, and will probably use it as an ongoing future reference for the class, but running it hard on Positano has identified the need for a tweak in my caster calcs.
It'll probably run a touch better with a caster set around 5.0~5.4, and in fact i'm changing my calcs to work all my cars above 4.9 or so.

Tuning calculator project #35678-4b, in reference to my Version 6 A-class Porsche 911 993 GT2 tune, has me again testing a new way to formulate damping values,....so when the basic car tests are done, i'll throw the FXX at it and see what it comes up with. The ratios will remain similar but the dynamics should loosen up. That may address the under/oversteer issue my tune had and assist with mechanical grip.

No real performance gains are expected, i'm just trying to improve feel.

God I love tuning.

[Fit4aking]

Feuer.  Thanks for trying out the IROC today!  I'm glad the car is good in the hands of someone other than me.  It was a decent car out of the box but the biggest increase in overall stability came when I applied your damping theory to it.  I only had to adjust rebound by 0.1 on both ends to get it to fall in line and handle how I wanted it to.  The way I see it if the same goes for the FWD Hyundai I'm going to compare it to than this method will indeed become a staple of my tuning setups. 

Springs 40% of total weight
ARB's in the 36-40 range
Dampers 8.0 and 4.0 (Rebound and Bump respectively)

All for base settings and then adjust from there.  So far each car I've tried in that layout has done well.  I have a Delta EVO built up and ready to toon after I finalize those two.  That will be my AWD addition to the D-class stable.  You and Spiny had one very beneficial conversation here.