Author Topic: Tuning Advice  (Read 1499 times)

PhantomGinn

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Tuning Advice
« on: August 19, 2011, 01:10:46 PM »
Hey guys, just have a few tuning related questions I wanted to ask, as I'm still new to this type of tuning.

1. Camber thrust. Is this a factor in setups at all? Or should camber be primarily used to help even out tire temperatures across the "outside tire," by which I mean the tire that is more frequently outside on a given track.

2. SB, SWR, etc. Is there a specific relationship between the SB, SWR settings for the calculators between classes, meaning are the SB and SWR settings a percentage higher or lower for R-class cars as compared to F class cars? I've noticed that the settings seem to be a bit higher as you increase in PI, I was just wondering if there was a specific rate of increase, or if it was done by feel.

If there are posts regarding these topics, I apologize for wasting board space, and I'll go search for them, and if this is in the wrong place feel free to move this thread. Either way, thanks for the help, and in general thanks for having these forums, my setups have gotten significantly faster from a lot of the reading I've done here and the calculators.

Blooze

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Re: Tuning Advice
« Reply #1 on: August 19, 2011, 02:34:01 PM »
Quote
1. Camber thrust.  ???
I don't know if I've seen that word associated with Camber before, but assuming that your question is about the plain old Camber that I understand then...  The Camber setting is used to get as large a contact patch as possible when the tire is under stress in a turn.  The temperature is not so much a goal as it is a means of determining if you have the Camber set correctly and the patch is as large is can be in this particular corner.

Really Really hot inside or out is not desireable because it means the patch is smaller.  The ideal, or the best that I have ever been able to get it is a 9-10 degree delta across the tire, with the higher temperature on the inside.

Quote
2. SB, SWR, etc...

I personally don't use any sort of adjustment that is based on the Class.  I set the SB to 50% by default and only move off of it if extreme conditions dictate.  Usually changing the ARB bias will fix most problems.  The SWR is dictated by how hard you want the springs to be.  I have found that the default values are a bit too strong for my taste  (how does it react to rumble strips; does the F to R weight shift suit you?)  so I start a few percentage points below what ever stock is.  For instance, if the stock SWR is 51.56%, then I may start with a 44.00% and work my way up from there.

Hope that helps some...
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« Last Edit: August 31, 2011, 12:15:10 PM by Blooze »
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PhantomGinn

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Re: Tuning Advice
« Reply #2 on: August 19, 2011, 03:47:16 PM »
Yeah that helps with the SWR settings. As the camber thrust goes, I think we are talking about the same thing. When I think camber, I think of the specific angle, and the "thrust" is the extra grip gained from running a camber angle. Maybe I haven't played with it enough, but I hadn't seen a whole lot of difference between running too little camber and too much camber, other than when the tire temps get too high and the car breaks loose, so I was curious how much of a factor it played in a setup other than balancing temperatures.

Also, I've noticed references to Spiny's ARB fix/mod to the calculators, how exactly does that work?
« Last Edit: August 19, 2011, 03:54:05 PM by PhantomGinn »

Blooze

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Re: Tuning Advice
« Reply #3 on: August 19, 2011, 04:15:37 PM »
The Spiny Fix is an adjustment I make to the ARB to affect oversteer.  So named because of his most common statement when he was commenting on one of my Toons, "...not quite loose enough for me..."

On my tuning sheet, the default setup is that the ARB are set to the inverse of the Spring Bias.  Since my SB is normally 50%, this means the ARB Bias is 50% as well.  The Spiny fix is for me to override the default behaviour and (in the case of an AWD or FD that is a bit pushy) and set it to something like 48%, effectively stiffening the R ARB.  And, finding that adjusting the bias was not quite enough, I also increased the Total ARB by a given percent.  So a Spiny Fix of 48/10 means I will be setting the ARB Bias to 48% and adding an additional 10% to the Total ARB.

I have found that with particularly persickitty MR and FR cars can benifit from this sort of build; where the SWR is set to 50% and the Spiny is set to 52/15 or something like that.

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PhantomGinn

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Re: Tuning Advice
« Reply #4 on: August 19, 2011, 04:29:58 PM »
Ah cool thanks

Spiny Anteater

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Re: Tuning Advice
« Reply #5 on: August 20, 2011, 03:08:08 AM »
Blooze is absolutely correct that it's not ideal to have a really hot side to the tyre, although sometimes you can end up with what appears to be a very warm right side compare to the left side if you're testing on a track which has lots of left handed corners relative to right-handed. Generally in such a circumstance I try to get the outside tyre within the 9-10 degree range and let the inside tyre go hang.

On the subject of camber, I had the alignment done on my car a couple of months back and decided to see how the values related to the same car (Focus ST) in Forza by the simple experiment of standing the car still and looking at the values. And the real life values were significantly higher than the Forza values of -0.5 degrees or so for each tyre. If anyone is interested, the camber values (all figures in degrees) were:

Front Camber: -1.01 Left, -0.50 Right (probably to do with us driving on the left so the car is naturally pulled left due to the camber of the road)
Rear Camber: -1.51 Left, -1.49 Right (as I said, much higher that Forza, even compared to my usual tuned values)
Toe: +0.13 Front, +0.34

The printout also shows a "thrust angle" of -0.01 degrees which again shows how a road car is set-up to pull very slightly to one side to cater for the crown of a normal road.
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PhantomGinn

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Re: Tuning Advice
« Reply #6 on: August 20, 2011, 02:53:43 PM »

On the subject of camber, I had the alignment done on my car a couple of months back and decided to see how the values related to the same car (Focus ST) in Forza by the simple experiment of standing the car still and looking at the values. And the real life values were significantly higher than the Forza values of -0.5 degrees or so for each tyre. If anyone is interested, the camber values (all figures in degrees) were:

Front Camber: -1.01 Left, -0.50 Right (probably to do with us driving on the left so the car is naturally pulled left due to the camber of the road)
Rear Camber: -1.51 Left, -1.49 Right (as I said, much higher that Forza, even compared to my usual tuned values)
Toe: +0.13 Front, +0.34

The printout also shows a "thrust angle" of -0.01 degrees which again shows how a road car is set-up to pull very slightly to one side to cater for the crown of a normal road.

Out of curiosity I looked through some documents to find the camber numbers for the cobra, and I found similar numbers for the front setup (the Rear is a special case, being a solid axle and all). From these numbers, it definitely seems like the numbers are a bit low in game. Have you run the Forza Focus ST with the realistic camber setup? I'm curious how that would perform (admittedly you would have to choose which front angle to run) in game.

And I will have to start using the tire setup you and Blooze have mentioned, more often than not my camber and the tire pressures are not as well employed as they should be... my focus tends to stick more with the differential, springs, dampers, and ARB.

Also, new question: Do you all set your aero settings in a similar manner as the SB as stated by Blooze? Aero would be for higher class cars (B class is usually where aero kicks in for me, though I have one C class with aero that works pretty well), as lower classes would benefit more from having the speed lost from those kits.

Spiny Anteater

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Re: Tuning Advice
« Reply #7 on: August 21, 2011, 03:06:22 AM »
I have to admit that running the realistic Focus setup was one of the "round tuit" process which I haven't got around to get. But the problem as I see it is that I only have figures for the alignment - all I know about the springs is that they're about an inch lower than a standard Focus and about 30% stiffer. I suspect they will affect the handling at least as much as the alignment, hence the project being on the backburner a bit. I am quite surprised to see that the values are similar to the Cobra though - I imagined RWD would have required a different setup.

Onto the aero, and I'm not quite so disciplined as Blooze when it comes to the settings. As you've said, it does play a much bigger part in the higher classes and certainly by the time I'm in the rarified air of S and R3 it's needed on most cars almost all of the time (Le Mans and the bigger ovals being the exceptions). And at the other end of the scale I usually only use it in F Class on the shortest tracks where top speed is irrelevant. But in the end, it comes down to which track I'm tuning for and the car I'm tuning. For example, about a year back I did a Porsche 914/6 with full aero which was great going downhill at Kaido almost getting into the top 40 (it's dropped out of the top 100 now :'() but it lost out heavily in races on any track with a semblance of a straight. So for me, it's much more a case of horses for courses when it comes to adding aero.
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PhantomGinn

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Re: Tuning Advice
« Reply #8 on: August 22, 2011, 12:06:39 AM »
I think the difference in the setups mostly involves the rear of the vehicle, as the Cobra has a negligible rear camber due to the solid axle. For the front, it makes some sense, as both a Focus ST and a Cobra are a bit nose heavy. The interesting thing to look into (to me at least) would be how the camber would change during travel; that would be a good look into how similar the front suspensions are set up, though that's not something that can really be tested without a lot of equipment, nor would it correlate to the game. After rolling several cars, I've noticed things such as IRS, solid axles, de dion axles, etc for rear and double and single control arm setups for front suspensions aren't exactly accounted for (and there is a lack of things like axle tramp on solid axle cars, also a good tell). Well, that, and it would add lots more work to the developer's plates to include that stuff.

On the Forza ST with real life settings, that makes sense, its pretty hard to find spring rates for certain cars. I also find it kind of annoying that Forza doesn't use actual stock spring rates for the cars, but I can understand why they don't.

For aero, that make a lot of sense; to be honest, tuning a car specifically for a track makes more sense to me than tuning for general use, its just something that takes more time than I'm willing to give usually, so I settle more often than not with a general tune.

Last (probably) question for general tuning stuff (next will probably be help with specific tunes, though as of right now I haven't had a setup that is too unruly), which steering wheel would you all recommend?


« Last Edit: August 22, 2011, 12:10:48 AM by PhantomGinn »

Blooze

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Re: Tuning Advice
« Reply #9 on: August 22, 2011, 06:31:44 AM »
I don't get all that scientific with my Aero settings, mostly because I haven't spent much time with the Aerodynamics settings and how what affects what.  One reason for all this hap-hazzardry is that I don't think Turn 10 does all that much with it either.  The affects of Aerodynamics are highly dynamic, with speed, barometric pressure, humidity, and the proximity of other cars all having their affect and changing on a second by second basis.

The R cars have a symetry to their Aero values that you don't find on the production cars.  That is that, no matter the setting, the default is 80% of the maximum and the minimum is 60% for both the front and rear.  Past that, I can find no consistency in changes to the G@120 BM based on Aero settings.  Just, increase it, the grip goes up, decrease it and the grip goes down.

But these are more or less static settings, and I believe that that is as far as Turn 10 takes it.  There may be a percentage change in the car's friction coefficient as the speed changes if the Aero parts are detected, but it is dealing with a fixed coefficient that calculated and saved to the car's profile when one exits the Tuning screen.  I would bet that the percentage change per mph is the same for all cars.  And it may even be more simple now that the computer is dealing with 12 cars now and the box is still the same as it was when it was dealing with 8.

So with all that said, here's how I handle the Aero settings.  Except for one or two cars per class that I use to set times on the ovals and the Le Mans big tracks, I usually run the values out to the maximum.  I've messed with other settings but find that, except for the tracks mentioned, full aero works best, no matter the class.

But, that is just me - others more than likely have other ideas...

As for wheels, my rig is the Fanantec 911 Turbo S with the Sequential shifter and the Microsoft pedals.  This is all mounted on a Fanantec wheel stand.  I think it works... fanantastically?  :P

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Spiny Anteater

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Re: Tuning Advice
« Reply #10 on: August 22, 2011, 12:16:46 PM »

But these are more or less static settings, and I believe that that is as far as Turn 10 takes it.  There may be a percentage change in the car's friction coefficient as the speed changes if the Aero parts are detected, but it is dealing with a fixed coefficient that calculated and saved to the car's profile when one exits the Tuning screen.  I would bet that the percentage change per mph is the same for all cars.  And it may even be more simple now that the computer is dealing with 12 cars now and the box is still the same as it was when it was dealing with 8.


I think you're probably right about the fixed co-efficient. I don't know if you remember but back in FM2 I felt that I got better traction off the line in a car with maximum downforce than one with minimum downforce (I think it might have been an R3 Ferrari, but it's a long time ago so I'm probably wrong). Things don't seem to have changed a lot on that score with FM3 so I still suspect that, as far as traction and grip rather than acceleration are concerned, the downforce is a fixed value (hence we add lbs of downforce with the spoilers) rather than a dynamic setting.

As for wheels, I can't comment as I'm still on the controller.
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feuerdog

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Re: Tuning Advice
« Reply #11 on: August 23, 2011, 12:39:05 PM »
On aero - I tried to keep my aero settings within a certain relationship to eachother.

I typically ran a 2/3 to 3/2 ratio fron to rear, and could run those values from minimal to maximized depending on the needs of the car/tune.

RWD's i'd prefer 2:3 downforce ratios
AWD's were around 1:1
FWD's were around 3:2

But keep in mind these ratios were further supported by the tuning calcs, and aero/damper/spring biases.

PhantomGinn

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Re: Tuning Advice
« Reply #12 on: August 24, 2011, 05:28:42 PM »
Thanks Fdog, I'll have to keep that in mind with my setups.

Well, for FM3, thats about all the questions I have, so from here I'll start posting up tunes for y'all to look at from time to time. As of right now, I won't be posting anything for a little while (in this thread), but I'll put up some tunes in the near future.

PhantomGinn

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Re: Tuning Advice
« Reply #13 on: August 29, 2011, 10:29:17 PM »
Well, now that my questions have been answered sufficiently, I guess its time to put up a few tunes to see what you guys think. I'll start with these two, a C425 Honda S2000, and an A600 '07 Ford GT500. They will be in the following posts.
« Last Edit: August 29, 2011, 10:41:11 PM by PhantomGinn »

PhantomGinn

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Re: Tuning Advice
« Reply #14 on: August 29, 2011, 10:40:46 PM »
First, the S2000

C425 Honda S2000
Hp: 263
Tq: 171
Weight: 2572
Cost: 79,000 Cr
QR: 205.084 (Average QR for the class is 205.847)

Build:
Race Air Filter
Race Platform and Handling, Sport Weight Reduction
Street Clutch
Sport Transmission
Sport Driveline
Race Differential
205/40/17 Front, 225/40/18 Rear
Hole Shot Hole Star wheels
Forza front splitter and rear wing

Tune:

Gearing: FD 6.00
            Front                                Rear
Tires:    29.0                                  29.5
Camb:   -1.1                                  -0.8
Toe:       0.0                                   0.0
Caster:   5.0
ARBs:     7.9                                    7.9
Springs:  415.5                                415.5
Ride H:    4.9                                   5.0
Rebound: 6.0                                   6.0
Bump:     3.0                                   3.0
Aero:      100                                  200
Diff:Accel 22%, Decel 8%

« Last Edit: August 29, 2011, 10:48:30 PM by PhantomGinn »