Is Suspension Tuning Backwards? - A Test with RX-8
- Thread starter Maturin
- 458 comments
- 45,202 views
!- 20
sukerkin, no problem on the names. I get called NN most of the time on other forums anyways! 
Greyout, very informative post, thanks for the read. And sadly I feel the same way, loosing interest fast :-(
I also noticed the GT4 physics doesn't account for the torque put on the chassis of the car from the engine. Too many flaws to be considered a driving sim.
The guys from LFS neet to team up with PD. Imagine the LFS physics engine (especially the D2 version) with GT4 graphics, tracks, cars and features (photomode!). We can only dream...
Greyout, very informative post, thanks for the read. And sadly I feel the same way, loosing interest fast :-(
I also noticed the GT4 physics doesn't account for the torque put on the chassis of the car from the engine. Too many flaws to be considered a driving sim.
The guys from LFS neet to team up with PD. Imagine the LFS physics engine (especially the D2 version) with GT4 graphics, tracks, cars and features (photomode!). We can only dream...
- 466
I think I might feel worse about continuing to enjoy this game if people were losing interest because it was too EASY to beat.
By the way, I don't know about "driveline torque" per se. I do know that my current tunes are feeling better with lower compression damping in the rear. I also remember reading somewhere that drive shaft "jacking" could be compensated for with softer compression damping. Coincidence? You decide.
By the way, I don't know about "driveline torque" per se. I do know that my current tunes are feeling better with lower compression damping in the rear. I also remember reading somewhere that drive shaft "jacking" could be compensated for with softer compression damping. Coincidence? You decide.
- 2,063
I have to say Aarque that my 'standard' setting for dampers tends to be of the order of Bound 5/4 Rebound 9/8 (in GT3 of course) for a reasonably powerful FR. So I'm pleased to see that you too are favouring the softer Rear Bound path - it gives me hope that I'll be able to translate tuning suites across without too much fiddling 👍.
Maturin
I don't think it is a bug in the game but more realistic.......................it is all dependent on where the engine is located and how low the ride height is, i.e;
The Mazda RX 8 is a front engine, rear wheel drive car so technically the spring rate should be increased up front because this is where all the weight is distributed. By increasing the stiffness in back, it would/should produce understeer because the car's inertia is still throwing it forward and the front tires are not able to toe and grip as well since the springs are "weaker" up front.
Try distributing more weight to the back and then retry the same car with your settings (I bet you will get different and more desirable results).
I also find an increase in cornering control when you increase both the front and rear camber by one.
- 2,063
@LedaM3 - my dear fellow, if you're going to be perjorative at someones posts then please at least have the decency to be right.
As it happens, it is actually true that the stiffer end of a suspension system will have less grip and also experience greater weight transfer in general (we won't go into the effects of springs that are too soft at this juncture). Also, what Greyout posted about loading is also correct; I fear you didn't read it properly.
@Dnomarz -first welcome to the discussion. However, I'm afraid that you appear to have grasped the wrong end of the stick with regard to how spring rates work.
Whilst it is true that a front engined car needs springs of a given strength to support the weight of the mechanicals, when you get up to the spring rates commonly used in motorsports that really becomes much less of an issue. It is one of the more widely accepted axioms of tuning that higher spring rates at the rear causes oversteer and higher rates at the front causes understeer.
I don't think anyone who has substantially contributed to this debate will question that that is the state of affairs in the 3D, tactile world. However, some are questioning whether this fairly fundamental fact has been properly implemented in the game code. The matter is under investigation and in a week or so I think we should have a pretty definitive answer.
Stay tuned
As it happens, it is actually true that the stiffer end of a suspension system will have less grip and also experience greater weight transfer in general (we won't go into the effects of springs that are too soft at this juncture). Also, what Greyout posted about loading is also correct; I fear you didn't read it properly.
@Dnomarz -first welcome to the discussion. However, I'm afraid that you appear to have grasped the wrong end of the stick with regard to how spring rates work.
Whilst it is true that a front engined car needs springs of a given strength to support the weight of the mechanicals, when you get up to the spring rates commonly used in motorsports that really becomes much less of an issue. It is one of the more widely accepted axioms of tuning that higher spring rates at the rear causes oversteer and higher rates at the front causes understeer.
I don't think anyone who has substantially contributed to this debate will question that that is the state of affairs in the 3D, tactile world. However, some are questioning whether this fairly fundamental fact has been properly implemented in the game code. The matter is under investigation and in a week or so I think we should have a pretty definitive answer.
Stay tuned
- 466
Don't stray too far with that stick, we may need it to beat this, er, thread. On a lighter note and soley to add substantive content to this thread, I can offer that during my current evolution in tuning, my efforts are focused almost entirely on the suspension category and within there mostly springs and dampers. Currently I consider it a compromise to have to adjust downforce or LSD to achieve the turning characteristics I desire, I am even subordinating my precious brake steering to the spring tensions.sukerkin
Hi all,
Have been reading the posts here with interest (so just had to sign up) as I have been frustrated with setting up some cars as I would like, and it wasn't until I purchased the 427 Cobra that I developed a theory on what's happening.
Are the front and rear spring rates reversed in the physics engine?
This is the test done on the Shelby Cobra 427, stock except suspension w/s2 tyres
Default set up
Springs f4.8/r4.2
Height 111/111
Bound f8/r8 'used f5/r5
Rebound f8/r8
Camber 2.0/1.0
Toe 0/0
Stability 4/4
Ended running this with damper bound at 5 as I felt that with such soft springs it was overdamped.
A simple change that makes a big difference
Springs f3.8/r4.8 'note spring rates reversed
Height 111/111
Bound f5/r5
Rebound f8/r8
Camber 2.0/1.0
Toe 0/0
Stability 4/3
The odd thing to note here is that the spring rate is opposite to what you would expect, the front is soft and the rear is hard, yet all other setting are, and act as I would expect.
This brought me to the conclusion that although the graphics engine shows a car with a lot of nose dive under breaking and little squat under acceleration if you go to the softest front and hardest rear settings, the car handles as if it had a hard front and a soft rear. Are the front and rear spring rates reversed in the physics engine?
From what I have tested with this car it appears that the dampers and stabilisers work on the correct end of the car as indicated in the set up screen, and that the dampers may not be "Magic" as with a very soft spring (2.8) a setting of 5 bound appears to stiffen that end (front spring set at 2.8 and rear bound at 5 ), further indicating that the springs are opposite to what is indicated in the set up screen.
Would be interested in others trying this and comparing notes.
I also think this may explain why I have had difficulty with other cars as softening the front of a car buy use of spring rate and stabilisers counteract one another. If you softened the front spring, and if it is the rear, and also remove some front bar what you have done is soften the the rear with use of spring rate, but also removed some of the front bar giving results that just didn't seem right. It may also explain why I felt that the test with Maturin's RX-8 gave me some unexpected results, as with the softening of the front spring there was also a softening of front bar and damper.
Have been reading the posts here with interest (so just had to sign up) as I have been frustrated with setting up some cars as I would like, and it wasn't until I purchased the 427 Cobra that I developed a theory on what's happening.
Are the front and rear spring rates reversed in the physics engine?
This is the test done on the Shelby Cobra 427, stock except suspension w/s2 tyres
Default set up
Springs f4.8/r4.2
Height 111/111
Bound f8/r8 'used f5/r5
Rebound f8/r8
Camber 2.0/1.0
Toe 0/0
Stability 4/4
Ended running this with damper bound at 5 as I felt that with such soft springs it was overdamped.
A simple change that makes a big difference
Springs f3.8/r4.8 'note spring rates reversed
Height 111/111
Bound f5/r5
Rebound f8/r8
Camber 2.0/1.0
Toe 0/0
Stability 4/3
The odd thing to note here is that the spring rate is opposite to what you would expect, the front is soft and the rear is hard, yet all other setting are, and act as I would expect.
This brought me to the conclusion that although the graphics engine shows a car with a lot of nose dive under breaking and little squat under acceleration if you go to the softest front and hardest rear settings, the car handles as if it had a hard front and a soft rear. Are the front and rear spring rates reversed in the physics engine?
From what I have tested with this car it appears that the dampers and stabilisers work on the correct end of the car as indicated in the set up screen, and that the dampers may not be "Magic" as with a very soft spring (2.8) a setting of 5 bound appears to stiffen that end (front spring set at 2.8 and rear bound at 5 ), further indicating that the springs are opposite to what is indicated in the set up screen.
Would be interested in others trying this and comparing notes.
I also think this may explain why I have had difficulty with other cars as softening the front of a car buy use of spring rate and stabilisers counteract one another. If you softened the front spring, and if it is the rear, and also remove some front bar what you have done is soften the the rear with use of spring rate, but also removed some of the front bar giving results that just didn't seem right. It may also explain why I felt that the test with Maturin's RX-8 gave me some unexpected results, as with the softening of the front spring there was also a softening of front bar and damper.
Should have mentioned that I use a PAL version of the game. I read somewhere that the physics engine was changed for the PAL version (did they introduce a bug?).
Try this,
Test 1
Take any car you want, I used a ZR-1, set the bound on the shocks to a low setting (I used 2, I don't think this influences the test but others may put me straight on this as its steady state cornering in interested in) set the front spring to min and the rear to max, set the front stabiliser to min and rear to max. All other settings std.
Test 2
Same car but this time with rear spring min and front to max while leaving front stabiliser at min and rear at max.
Note the difference in handling (I used Fuji 80s for this) set up 1 produced a car that still handled reasonably, not the massive oversteer I would have expected, but test 2 produced oversteer in bundles the rear just wouldnt stick.
Try this,
Test 1
Take any car you want, I used a ZR-1, set the bound on the shocks to a low setting (I used 2, I don't think this influences the test but others may put me straight on this as its steady state cornering in interested in) set the front spring to min and the rear to max, set the front stabiliser to min and rear to max. All other settings std.
Test 2
Same car but this time with rear spring min and front to max while leaving front stabiliser at min and rear at max.
Note the difference in handling (I used Fuji 80s for this) set up 1 produced a car that still handled reasonably, not the massive oversteer I would have expected, but test 2 produced oversteer in bundles the rear just wouldnt stick.
- 466
Thank you so much for your well reasoned and concise postulation. I could suggest you explore your phenomenon more thoroughly. Try using incremental values and identifying all parameters. You have not indicated any reason why your test vehicles COULD NOT be riding on the bumpstops - although it seems reasonable to assume that possibility since you have disabled all support at one end of the vehicle - and I think we can all agree that a bottomed suspension can respond like a very stiff spring.Kiljoy
Additionally, some of the contributors may have trouble when reading a post that describes adjusting numerous components to test the effect of one. In my opinion, stabilizers have nothing whatsoever to do with exploring the effects of spring reversal. They lever a loaded suspension component against the unloaded other side and thus produce a measure of stability through (a measure of) preventing the independant nature of your suspension. My advice: set them low, note that in your post, and forget them. Dampers convert the energy the road has forced into your chassis into heat (the springs basically sweeping up this heat and feeding it to them during the rebound stroke). If you have to set dampers at anything but their minimum for these tests, like to prevent bouncing (love to actually SEE that) it should be kept consistent and noted in the test write-up.
Hi Aarque,
The reason for the test with max min settings was to take what I had discovered with the Cobra and take it to exremes (being over dramatic I suppose). I wanted to test whether the front spring is in fact the front spring (please.. do you have a better test for this?), by softening it and at the same time increasing roll stiffeness, I was hoping that there would be a certian amount of cancelletion of the effect of softening the spring. The test dosen't have to be quite so extreme to get this effect, as I agree that if the suspension bottoms it will act as if it is on a spring of infinite stiffeness.
Also it is steady state cornering Im trying to test this in so ignore any transitional oddities that the test set up may have, also why I chose Fuji for the test.
But please any input, criticisms will be well received
The reason for the test with max min settings was to take what I had discovered with the Cobra and take it to exremes (being over dramatic I suppose). I wanted to test whether the front spring is in fact the front spring (please.. do you have a better test for this?), by softening it and at the same time increasing roll stiffeness, I was hoping that there would be a certian amount of cancelletion of the effect of softening the spring. The test dosen't have to be quite so extreme to get this effect, as I agree that if the suspension bottoms it will act as if it is on a spring of infinite stiffeness.
Also it is steady state cornering Im trying to test this in so ignore any transitional oddities that the test set up may have, also why I chose Fuji for the test.
But please any input, criticisms will be well received
- 466
I will gladly share feedback and even some experementation, but such a test is what I believe this thread was created to define. Perhaps you could establish a neutral point, then go from there. Maybe use b-spec Bob to remove subjectivity and ask him to push extremely slippery tires down a long straight into a hairpin; if your Bob isn't too skilled the results could be dramatic. Then you could change one spring one click and try again. If you see any noticeable change you might be on to something.Kiljoy
I must confess the actual issue of reversal has little consequence to me. Like the threads originator, I am an empiricist and am only concerned with what will make my McLaren faster than my buddies.
- 34
Okay here is a really weird test for the messed physics engine in GT4.
Take a 1990 Honda Crx with a racing suspension and a stage 3 NA tune, and all of the other top of the line modifications.
Go to Tsukuba raceway in practice mode
Test 1
Use these settings
front/ rear
Springs Rate 16.0 / 5.0
Ride Height 133.0 / 133.0
Bound 3.0 / 3.0
Rebound 8.0 / 8.0
camber 2.0 / 1.0
Toe 0 / 0
Stabilizers 6 / 2
TCS 0
ASM Over 0
ASM Under 0
Brakes personal preference
LSD leave it
Tires N2 or S2
Okay from what I know and have read on this forum and is written in my purchased automotive tuning books. This car should under steer all of the time. The reason the suspension is very stiff in the front and the dampers are tuned for understeer. Added bonuses a Front wheel drive car with a lot of power and no traction control should understeer on basic principle. Just a one tips point the front tires which way you want to oversteer and give it a lot of gas it can even drift if you want it to.
On a personal note a drive a stock 90 Civic Si in real life with less horse power no TCS and it understeers when driving fast through a corner with the throttle pinned
Test 2
Use these settings
front / rear
Springs 5.0 / 16.0
Ride Height 133.0 / 133.0
Bound 8.0 / 8.0
Rebound 3.0 / 3.0
camber 2.0 / 1.0
Toe 0 / 0
Stabilizers 2 / 6
TCS 7
ASM Over 0
ASM Under 0
Brakes personal preference
LSD leave it
Tires N2 or S2
Opposite settings should equal a good amount of oversteer even though it is front wheel drive car.
Nope
I know there is a big variation in both setups but the end result should not be what it is in the game.
Also if you could give me a general idea how theses settings would work in real life. Either right or wrong and why any criticism is welcome and I will explain my stance in greater detail. Thanks
Take a 1990 Honda Crx with a racing suspension and a stage 3 NA tune, and all of the other top of the line modifications.
Go to Tsukuba raceway in practice mode
Test 1
Use these settings
front/ rear
Springs Rate 16.0 / 5.0
Ride Height 133.0 / 133.0
Bound 3.0 / 3.0
Rebound 8.0 / 8.0
camber 2.0 / 1.0
Toe 0 / 0
Stabilizers 6 / 2
TCS 0
ASM Over 0
ASM Under 0
Brakes personal preference
LSD leave it
Tires N2 or S2
Okay from what I know and have read on this forum and is written in my purchased automotive tuning books. This car should under steer all of the time. The reason the suspension is very stiff in the front and the dampers are tuned for understeer. Added bonuses a Front wheel drive car with a lot of power and no traction control should understeer on basic principle. Just a one tips point the front tires which way you want to oversteer and give it a lot of gas it can even drift if you want it to.
On a personal note a drive a stock 90 Civic Si in real life with less horse power no TCS and it understeers when driving fast through a corner with the throttle pinned
Test 2
Use these settings
front / rear
Springs 5.0 / 16.0
Ride Height 133.0 / 133.0
Bound 8.0 / 8.0
Rebound 3.0 / 3.0
camber 2.0 / 1.0
Toe 0 / 0
Stabilizers 2 / 6
TCS 7
ASM Over 0
ASM Under 0
Brakes personal preference
LSD leave it
Tires N2 or S2
Opposite settings should equal a good amount of oversteer even though it is front wheel drive car.
Nope
I know there is a big variation in both setups but the end result should not be what it is in the game.
Also if you could give me a general idea how theses settings would work in real life. Either right or wrong and why any criticism is welcome and I will explain my stance in greater detail. Thanks
- 466
I am so confused. I think we are exploring a phenomenon; I read detailed and inquisitive posts, I consider the evidence, I offer feedback and suggestions...and it seems like we are more or less on track. Now here comes another automotive physics "inquisitist" who has purportedly read through the discussion thus far and wants feedback on the results of his wildly dissimilar tests (at least the third on this thread). Ok, here it is. I learned this in kindergarten, but maybe it was the advanced class. Rule #1: You can't mix apples and oranges with numbers. 4 apples + 2 oranges +7 = how many fruit? The scalar numbers for the damper settings HAVE NO VALUES, I cannot fathom why somebody would be compelled to compare them to any existing thing in real life, since they have never experienced it. Oh, you think your "Lotta" dampening in your BMX shock or your frikkin Acura strut is in any way similar, in a quantifiable form, to the lotta damping in a virtual race prepped Civic? Rule #2: When measuring state changes, remove unnecessary variables. Since we don't know what damper setting #8 is, except that there are 6 more steps between it and setting #1, it is conceivable that for the energy levels (speeds) involved in this test, it would be all but immobile, which would make it "feel" like a stiff spring. So, if this damper actually feels STIFFER than a stiff spring and you go swapping your supposedly stiff spring to the back expecting your front to be softer, well son, I have a fence here I just might let you whitewash, if you pay me enough. Rule #3: When mapping state changes, the smallest practical increment provides the most accurate results. it is flawed logic to assume that since the suspension acts the same at either extreme it will be the same throughout its range. There are gradual changes between unlocking your shock (from loosening a taught spring), to bottoming your suspension (from removing too much spring tension); I encourage you to explore them and I will be happy to reflect on your results.
Thank you all for the spirited debate. It's great to see great minds at play (work?). Anyway, I've been an avid GT'r since GT1. I cut my teeth on car settings in GT2, but did it largely by feel (I'm not an engineer, or a racer, but I dearly love fast cars and racing.) I pursued car settings in GT3 with the Skip Barber "Going Faster" book in hand, but was frustrated in trying to apply real world numbers in the spots where GT seemed to have values assigned on a range (of 1-10, say, or somesuch.)
In the context of all you've said here I have a noob question about spring rate values as listed in my (American) version of GT4. They're listed in kgt/mm. I assume that the higher the number, the more weight/force required to compress the spring (so that a value of "9" is stiffer than a value of "7". Is this assumption correct?
Given that, I was working on an understeering Lotus Espirit 87 HC and ended up assigning the front springs at 7.4 and the rears at 9.4, assuming that I was softening the front, relative to a stiffer rear. If I read the book right, I understand that this should help my understeer problem. (the stabilizers and bound/rebound I've left equal front and back to eliminate variables. Since I lowered the ride height, I input more restrictive bound/rebound values in order to keep from bottoming out.) Well, it seems to have done as advertised, so I can't complain. Understeer has been tamed, the car turns in nicely, and will still turn past the apex while under throttle. However, I am trying to follow all the messages on this thread and just wanted to throw my two cents in.
Springs (f)7.4 (r)9.4
Ride (f)111 (r)111
Bound (f)5 (r)5
Rebound (f)5 (r)5
Camber (f)2.0 (r)1.0
Stabilizers (f)4 (r)4
Thanks for all your work, I'll keep reading and learning!
K|:-)
In the context of all you've said here I have a noob question about spring rate values as listed in my (American) version of GT4. They're listed in kgt/mm. I assume that the higher the number, the more weight/force required to compress the spring (so that a value of "9" is stiffer than a value of "7". Is this assumption correct?
Given that, I was working on an understeering Lotus Espirit 87 HC and ended up assigning the front springs at 7.4 and the rears at 9.4, assuming that I was softening the front, relative to a stiffer rear. If I read the book right, I understand that this should help my understeer problem. (the stabilizers and bound/rebound I've left equal front and back to eliminate variables. Since I lowered the ride height, I input more restrictive bound/rebound values in order to keep from bottoming out.) Well, it seems to have done as advertised, so I can't complain. Understeer has been tamed, the car turns in nicely, and will still turn past the apex while under throttle. However, I am trying to follow all the messages on this thread and just wanted to throw my two cents in.
Springs (f)7.4 (r)9.4
Ride (f)111 (r)111
Bound (f)5 (r)5
Rebound (f)5 (r)5
Camber (f)2.0 (r)1.0
Stabilizers (f)4 (r)4
Thanks for all your work, I'll keep reading and learning!
K|:-)
Keith S
Those spring rates are exactly the sort of rates percentage wise that you should be getting for a mid-engined car and I am glad that you have found that the tuning works to your liking
Reading the last couple of pages it seems to me that people are getting hung up on the actual numbers of each setting, especially when looking at spring rates.
I myself have a couple of FR cars with the rear spring rates close to or higher than the front spring rate but they still respond to the usual spring rate changes in the correct ways
Those spring rates are exactly the sort of rates percentage wise that you should be getting for a mid-engined car and I am glad that you have found that the tuning works to your liking
Reading the last couple of pages it seems to me that people are getting hung up on the actual numbers of each setting, especially when looking at spring rates.
I myself have a couple of FR cars with the rear spring rates close to or higher than the front spring rate but they still respond to the usual spring rate changes in the correct ways
Took me two days to do it but I've read each post. I see all the tests and scenario's, but I'd like to ask if I had a car that "I'm going a little stiffer on the rear springs", and "a little softer on the front springs", will I get the response that most books/professionals and real world physics will say I should get? Which in this case would be a car who's rear end is getting "a little more" grip than it did before the slight setting changes?, and the front end is getting "a little less grip"? If that's the case, I don't need to worry about this issue where these spring settings are being put to extremes and exibiting this odd behavour.
Thanks "G"
Thanks "G"
- 466
I have found when working with spring tensions to control steering characteristics, that incrementally increasing rear tension increases oversteer this is what I have come to understand is expected. However, I usually get more noticeable results when I add 2 units to the rear and one unit to the front to induce oversteer. The sensation I get when I just drop one click up front (usually), is that the suspension feels too pushy soft, overriding any change in oversteer. Your "little more grip" comes from whether the dampers can keep the wheels exactly pressed against the ground.goldbadge
- 723
Can I get some settings for my 1000HP Skyline?
Sorry, couldn't resist.
Nice to see lots of real world racers here. 👍
I just read (and re-read if necessary) every single post in this thread in one sitting. That was about 4 hours worth.
I laughed and shook my head several times. I also agreed and dis-agreed as many times. Lots of good posts here, and a few not so good.
My general thought and comments on this entire thread are as follows...
I'm going to have to side with the real world guys on this one, although I do think it has a LOT to do with driving style (or lack of).
I think the R/C racers have a slight upper hand on this one one though (ex-partially sponsored 1/10 electric touring car racer here too.
).
My reason:
With R/C it is much easier to change settings and swap parts (like stiffer/softer springs). Not to mention the wide array of parts and FULLY adjustable suspension we have. It is easy to test an extreme to see it's effects and most of us at the higher levels of R/C racing have tried the extreme (you have to when you can throw your tires at the wall and they stick there
).
I have done my fair share of kart racing (4+ years of IKF), auto-x (SCCA and BMW Club) and open track days (Sears [Infineon] and Laguna). So I also have my experience, admittedly somewhat limited, with that to go on as well. I have also done OLR racing and i-linking with GT3 for well over a year now.
I have noticed that most cars (I have 424 in my GT4 garage so far) do not like extreme tuning AT ALL. Lap times suffer dramatically and handling is highly inconsistent. Much like extreme tuning in RL.
I have also noticed the game does not like FULL throttle, braking or turning. All you get when doing one of those is understeer. Mighty difficult to modulate with my old DS2. DFP will be set up soon, the old DS2 just isn't cutting it.
What I think the guys that believe the springs are "backwards" or the "physics engine is totally screwed up" are experiencing is lack of actual knowledge and experience driving and/or tuning real cars. You simply can't run extreme settings or it will throw off the entire car. In the real world and seemingly on GT4.
In GT3 it seemed as though PD stopped the adjustment sliders before it allowed you to run extreme settings, where GT4 does not stop there and requires you to have a better grasp on tuning so you don't go into these areas with-out knowing what you are doing.
One turn testing doesn't do much for me either. Find a comfortable car and your most familiar track, find your fastest lap time possible and then find your consistent fastest lap after lap time. Use that consistent fastest lap time to adjust your settings. Doing it slowy (small increments) and one setting at a time starting from default. This also only works if you can actually drive. Try an OLR spot race to see if you can actually drive. Don't need a top time, but you should be able to get within a reasonable distance to a top time.
Real world settings will never work on an over the counter game (simulator
) in our lifetimes. Get over it, it's not going to happen. Some of your real world race settings knowledge may help you, but that's about it. Even in real life the settings may vary, albeit slightly, from chassis to chassis of the same exact type car. Your real racers should know this. R/C guys may not as the chassis are usually identical carbon fibre sheets and not welded together formed metal.
In closing I would like to say I have enjoyed this thread so far, learned a bit and got to brag a bit.
I look forward to more interesting posts and theories. 👍
Sorry, couldn't resist.
Nice to see lots of real world racers here. 👍
I just read (and re-read if necessary) every single post in this thread in one sitting. That was about 4 hours worth.
I laughed and shook my head several times. I also agreed and dis-agreed as many times. Lots of good posts here, and a few not so good.
My general thought and comments on this entire thread are as follows...
I'm going to have to side with the real world guys on this one, although I do think it has a LOT to do with driving style (or lack of).
I think the R/C racers have a slight upper hand on this one one though (ex-partially sponsored 1/10 electric touring car racer here too.
).My reason:
With R/C it is much easier to change settings and swap parts (like stiffer/softer springs). Not to mention the wide array of parts and FULLY adjustable suspension we have. It is easy to test an extreme to see it's effects and most of us at the higher levels of R/C racing have tried the extreme (you have to when you can throw your tires at the wall and they stick there
). I have done my fair share of kart racing (4+ years of IKF), auto-x (SCCA and BMW Club) and open track days (Sears [Infineon] and Laguna). So I also have my experience, admittedly somewhat limited, with that to go on as well. I have also done OLR racing and i-linking with GT3 for well over a year now.
I have noticed that most cars (I have 424 in my GT4 garage so far) do not like extreme tuning AT ALL. Lap times suffer dramatically and handling is highly inconsistent. Much like extreme tuning in RL.
I have also noticed the game does not like FULL throttle, braking or turning. All you get when doing one of those is understeer. Mighty difficult to modulate with my old DS2. DFP will be set up soon, the old DS2 just isn't cutting it.
What I think the guys that believe the springs are "backwards" or the "physics engine is totally screwed up" are experiencing is lack of actual knowledge and experience driving and/or tuning real cars. You simply can't run extreme settings or it will throw off the entire car. In the real world and seemingly on GT4.
In GT3 it seemed as though PD stopped the adjustment sliders before it allowed you to run extreme settings, where GT4 does not stop there and requires you to have a better grasp on tuning so you don't go into these areas with-out knowing what you are doing.
One turn testing doesn't do much for me either. Find a comfortable car and your most familiar track, find your fastest lap time possible and then find your consistent fastest lap after lap time. Use that consistent fastest lap time to adjust your settings. Doing it slowy (small increments) and one setting at a time starting from default. This also only works if you can actually drive. Try an OLR spot race to see if you can actually drive. Don't need a top time, but you should be able to get within a reasonable distance to a top time.
Real world settings will never work on an over the counter game (simulator
) in our lifetimes. Get over it, it's not going to happen. Some of your real world race settings knowledge may help you, but that's about it. Even in real life the settings may vary, albeit slightly, from chassis to chassis of the same exact type car. Your real racers should know this. R/C guys may not as the chassis are usually identical carbon fibre sheets and not welded together formed metal.In closing I would like to say I have enjoyed this thread so far, learned a bit and got to brag a bit.
I look forward to more interesting posts and theories. 👍
Tuff240
Amen
I would like to say though that with the RC cars each chassis is a little different, not much but definitely different, either it is small differences in the mold from chassis to chassis or just that each person can put the car together slightly different, probably a bit of both.
Goldbadge
I can't say i have ever seen a real world tuning guide or book that said that a stiffer spring will give more grip, everything I have read says that a softer spring (within reason) will give more grip
Amen
I would like to say though that with the RC cars each chassis is a little different, not much but definitely different, either it is small differences in the mold from chassis to chassis or just that each person can put the car together slightly different, probably a bit of both.
Goldbadge
I can't say i have ever seen a real world tuning guide or book that said that a stiffer spring will give more grip, everything I have read says that a softer spring (within reason) will give more grip
tuff240
Oh please....
Extreme values WILL throw off the car, and they do in the game - but not as they should!
Once again, the "extreme" values at each end of the spring rate slider ARE NO WHERE NEAR a rate that is "extreme" in real life. The softest setting is still stiffer then a stock spring, and the stiffest setting is a fraction of what many production cars run. Its one of only TWO sliders that have actual values associated with it, (the other is camber) so you'd think that the values listed had SOME attempt at accuracy.
plenty of people have run 8F / 12R, then 12F / 8R, and noted that the car behaves backwards. those are not extreme settings.
People are looking for way to have the car setup "just right" in order to prove that PD is correct. They are taking the stiff rear / soft front, and messing with EVERYTHING else (sway bars, shocks, driving method, or saying "you've gone too far") in an attempt to FORCE the car to behave the way the spring rates dictate it should.
Well all thats BS. If you've got 1200lb/in springs in the rear, 350lb/in springs in the front, assuming that your damping is SOMEWHERE in the same ballpark as it should be (and its apparent that the scale adjusts automatically, so thats not an issue), then you're going to get MORE OVERSTEER. It does not matter if you drive smoothly or not, it does not matter if you've got a degree of toe in or out, or if you've got 50lbs of ballast on one end or the other, or if your camber is dialed in just right. Those spring rates will cause the car to exibit relatively much more oversteer, compared to the reversed spring setup.
The "make small adjustments" argument is BS also. You want to add 0.3 kg/mm to the spring rate? WTF is that? They don't even manufactuer spring rates with such a small difference! If you add 0.3kg/mm and notice a small difference, adding 3.0 kg/mm will make a bigger difference! And more importantly, adding 6kg/mm will make an even bigger difference, not send the car into the 4th demention where logic & physics do not apply, and suddenly the FWD car with the iron-solid front suspension and the wet noodle rear suspension is drifting through the corners at full throttle.
GT4 In summary:
SPRING RATES: roll & pitch physics are correct, weight transfer is NOT.
SHOCKS: God knows
ALIGNMENT: We all debated wtf PD meant by positive toe and negative toe, and maybe we're right. Camber is a shot in the dark without pyrometer readouts.
SWAY BAR: waaaaaay to subtle to be useful. Ambigious slide scale attacks again.
GT4 👎
- 55
Anyone here has a JDM GT4? I heard it's a lot easier to drive. So it might be just the NA GT4 are messed up.
- 466
So mate, which of us chaps has his bonnet up his boot when I say 1 click will make 1 car lengths difference at the end of the opening straight at Deep Forest? Oh, perhaps you don't know what I am talking about. Could it be because you have never actually taken the time to run 1 lap with a particular setting, then compare sucessive tuning adjustments to your ghost? What could 1 car length for 2000 yards multiplied by a 10,000yard + course possibly mean to people who slap thier slide adjusters around like they were playing air hockey?Greyout
To anyone interested in actually LEARNING something here, I encourage you to keep participating. The rest of you hotheads that already know it all, wtf, why do you even frikkin care?
- 2,208
Greyout
Well, this is discouraging. Combine this with the stupid AI, the history-of-the-Japanese-car-industry car list, the infuriating difficulty you have getting a reasonably competitive field of AI cars in virtually every event, the screen shaking problem, and the countless number of little bugs people have found, and you come to the conclusion that PD has just made too many mistakes with GT4.
Sure, I'll get creative still have a lot of fun with it for a long time, as I did with GT3, but Kaz and Company have basically screwed the pooch. GT4 could've and should've been better.
Greyout
The extreme values of spring rates do throw the cars handling off, and as they should, I quite effectively showed that using my RC car example.
Greyout
The only problem with that statement is that almost all the spring rate tests I have seen on this thread have been accompanied by damper and rollbar changes which will throw out the window any useful comparison.
Greyout
Again we are talking about a make believe world here so who cares if you can't get springs made in 0.1kg/mm increments.
Small adjustments sure as hell do make a big difference to the handling of the cars. Making an adjustment of 0.2 to a spring does mean the difference between taking X corner in 3rd gear or being able to take it in 4th gear.
Something is not right but I don't think we can definitively say it is weight transfer.Greyout
aarque
I noticed that you said above
I hope that that is a typo on your part, either that or you have jumped on the "physics is backward" bandwagonaarque
I must stress that something is not right with how the cars handle but I don't think the physics are backwards.
One example is the fact that I find I have to be going at an obscene speed t obe able to get the car so spin wildly out of control.
Another example, and I have had this on many a hot lap, come around a fast corner get sideways and not be able to catch it, so I let off the gas and turn the wheel to make the car spin a full 360 so I can be on my way with a minimum of fuss and low and behold I get to not quite 180 degrees rotation and the front of the car suddenly decides to reverse it's rotation and go back the way it was coming from even tho the front wheels are pointed in the opposite direction
Here is some food for thought.
I play GPL quite a bit and it is widely regarded as a very good sim, the only problem is that it is too good and it's sales reflected that, most people found it just to hard because it was a good sim, now I don't think that PD is going to make that mistake, so they have obviously given up some amount of realism for playability
One last note
Do we really think that PD would make such a gross and stupid error to release a game with the physics reversed! and not recall them in a hurry when they found out, I think not, some PD engineers are prob reading this thread and laughing their asses off
Saying all that I have found GT4 a lot more fun than GT3 because the cars react in a far more realistic way to my steering and throttle inputs, and I have been able to tune my cars quite effectively
This is definitely how cars are in the real world, some cars are infinitely tunable and some cars are not.
Take for example the 911 Porsche, it has taken Porsche 30-40 odd years to get the car to a point where most normal people (ie. not racecar drivers) can drive the car fast on the road and not be scared ****less that it will bite them in the ass if they make one small mistake
maturin
This is definitely how cars are in the real world, some cars are infinitely tunable and some cars are not.
Take for example the 911 Porsche, it has taken Porsche 30-40 odd years to get the car to a point where most normal people (ie. not racecar drivers) can drive the car fast on the road and not be scared ****less that it will bite them in the ass if they make one small mistake
