Holy crap- give it a rest clairvoyantwolf, you have made it clear you are an insufferable pedant. No need to ruin the thread any further if you have nothing to contribute with regards to getting more rear traction out of Forza 4 tunes.
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He’s a troll, it’s kind of his job to start arguments. I’m just hopeful that eventually a mod will get tired of him picking fights with people and ask him to knock it off. That, or we can all just ignore him until he goes away. Either option works for me…
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I’ll leave this here as it’s an easy visual of the difference between open and locked:
The “locking” on a diff refers to locking the speeds of the two wheels together, which means they are putting out unequal torque (due to newton’s third law of motion). The behavior is the same when one tire has more traction due to weight transfer. As in this hill climb, the unloaded wheel (if this was a turn) would spin. With a locked diff the unloaded tire (the inside tire during a turn) would not spin, but the loaded tire would be producing more torque since it as more traction.
I will be bowing out of this conversations, unless specifically summoned, out of respect for Cool The Kid. If anyone still questions how a open vs locked diff works I suggest they take a car this winter with an open diff (most are) and put one tire on ice and the other on pavement and watch how they don’t go anywhere. Yes, the tire with grip is “locked” as Bulin and Roadrunner say, but the diff itself is not.
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Seeing as you think 100% = Open and 0% = Locked is wrong, well my question to you is, what does the percentage even mean eh?
Depending upon what you say will determine whether I know what you are thinking…
RR
From the tuning guide of Forza 4 itself:
“The Accel differential setting adjusts how much of a difference in wheel rotation is required to lock the differential under acceleration. Increasing the Accel setting makes the differential lock more quickly under acceleration.”
(emphasis added)
Let’s give a full inventory shall we. In this thread I described the mechanical difference between a locked diff and an open diff using my own words. I went on to say, in detail, how exactly that affects a car through a turn and on acceleration with uneven tire loads. I provided a personal example of the limitations of open diffs in the real world and why that is, plus how a locked diff would have changed the situation. I even provided video proof explaining the same. The only thing my opposition has been able to say back is, “Get a #1 tune or shut up.” I truely am wowed by that rebuttal. Anyway, as I said, I’m bowing out of this discussion unless summoned (like now). My parting remark is that if you ever buy a truck to go off roading make sure you check the “open diff” option box if you’re so sure about how a diff works. …Make sure you bring a shovel or cell phone to call a tow truck when you get stuck.
One last video on the difference between the two:
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Quoting the tuning descriptions in the game is a bit silly considering that they claim decreases the accel diff DECREASES understeer in FWD cars…
Ugh, I don’t wanna get any more involved with this, but…
To put it simply, having your diff set to %100 and %100 mimics having a welded diff, in the sense that it’s always locked. Having your diff set to %0 and %0 mimics having a completely open diff, in the sense that it never locks.
I’m no expert, but that’s my understanding of how it works. Now what is more useful in game? Meh, I’ll drive anything and everything. The settings are irrelevant to me personally…
In the meantime, may we all just take a deep breath and relax for a moment? Wolf’s said he’ll leave, so I’d like to take him up on that shockingly good offer and continue on with the conversation like normal instead of holding a [curse word] match.
I’ve been following this discussion, and to be honest I have tried to stay out of it. How ever I’m starting to get bored of it and therefore I add my opinion in to it, and Either I get proven wrong, or end the conversation as all partys agree.
Note: this is done completely ignoring the decleration diff setup, which plays a big role in there too.
Lets assume we have car. Lets assume the suspension of the car in dialed in correctly, and lets assume we are driving that car on a track, and lets assume that we are attacking fairly high speed but not flat out turn, For example the Road Atlanta 1st corner
Lets assume we have open (0%) differential setting. The weight of the car shifts left, and at the point we want to exit the corner we hit throttle and result is either
A. Whole lot of tiresmoke from our right drive tire, and no acceleration, the left side drive wheel managed to hold the grip, which would indicate that we could have held higher speed trough the corner at at least with the amount of grip this axle has. as only 1 tire which has grip manages to keep the car going in the wanted direction.
B. We overpowered the right drive tire, and as it lost it’s grip there is only 1 tire holding the car in line, as we suddenly lost grip on 1 tire (due overpowering it) the tire on left side cant handle it and loses grip too.
In both cases situation A results as poor exit out of the turn. In case of RWD, B results as oversteer / spin, and in case of FWD,B results as understeer.
Now lets do same assumption with constantly locked (100%) differential setting, Again the weight of the car shifts left, result is either
A. (RWD) The tires were fighting from traction all the way trough corner as they always rotate the the same speed The tire on the left won the fight cause of weight shifted on to it. Therefore the tire on the right side is constantly slipping because it isn’t travelling the same amount of distance as the tire on left side, Therefore it promotes understeer. How ever as the grip is “weakend” on this tire the left tire might not hold enough grip, and it might suddenly lose it’s grip, resulting as “snap” oversteer.
B. (FWD) …cause of weight shifted on to it. The car will suffer from heavy understeer. and if/when you add power to get out of the corner it will just get promoted even more.
Now lets take Limited slip diff. with ideal slip. How ever we don’t know what is ideal, so the ideal slip is “value X” and we are playing he game of “Find the X”. To make things simple lets just assume the ideal value is 50% (Which it probably never is, but let’s just go with it for now.)
So same assumption with LSD (50%) differential setting, Again the weight of the car shifts left, result is.
A. (RWD) The differential does not restirct the cars rotation at all, or only very limited amount, all tires are fighting the grip generated by G forces, and don’t “fight eachothers”. giving it the ideal cornering ability. When power is applied on corner exit, the LSD limits the power going to the tire with least grip (right rear) and forcing that power to left rear tire, Result is good acceleration out of the corner, with possible small understeer or oversteer, depending on the power applied, If the power applied is greater than both of the tires can handle, result is minor, and subtle oversteer, if it wasn’t the result is minor and subtle understeer.
B. (FWD) When power is applied on corner exit, the LSD limits the power going to the tire with least grip, (right front) and forcing that power to left front tire. Result is Result is good acceleration out of the corner, with highly likely small understeer, the severity of the understeer is entirely depending on how much power was added.
Before you put me down, Yes I don’t have the skill set on driving to set #1 times and it’s a fight to get even in top #250. Then again, I rather end up in top5 in a race with a -59 Cadillac in lobby full of Ferraris.
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I don’t know about anyone else’s opinion on that, but I find there is less understeer with a 100% diff on a FWD than a 0%… hence why I use 100% on all my FWD’s…
I see where you are coming from, and what you have described is what the Forza description says, but that fact that I don’t get this makes he think otherwise…
The way I see 100% and 0% is the rotational speed… 100% free to rotate at different speeds, 0% opposite which I’ve found is true.
Considering this, that would mean that 100% = Open and 0% = locked.
That’s my opinion and to be honest, I don’t care if other people think I’m wrong, I’ve produced and set No.#1 times in all my own tunes so I have to be doing something right, so either way - I’m just going to stick with my opinion. Some of youse may think, that I’m being rather straight minded - effectively stubborn but if that’s my opinion, I’m sticking with it until someone produces Forza data that suggests that I’m wrong (not real world - this is a game!) - and doesn’t use the telemetry as that is sometimes wrong as well!
RR
Man after my own heart. In a game with literally hundreds of cars it is quite frustrating to constantly race the same half dozen in lobbies.
Actually I do agree that high acc diff does reduce understeer But I’m inclined to belief that it’s more to do with the line you take the corner.
As in FWD you turn in slightly later and slightly harder, get on the throttle earlier (therefore locking the diff earlier) but you usually get better drive out of the corner, which relates on equal / better times as with other drive types.
Personally my FWD cars are running 90+/10- acc dec diffs always
High Acc for getting good drive out of the corner
Low Dec for getting the car turn in better. but because I usually run with fairly narrow tires on the back, there is tiny amount so it would restrict possible oversteer
Then again it’s actually pretty easy to test is 100% locked or open.
Take modearately powered RWD car, and go to some place where you can position your car halfway on grass, (indy GP, after 1st chicane for example) and do “brakestand burnout”
If your diff is set up to 100% you have both rear tires spinning
If your diff is set up to 0% the tire on the grass spins whole lot, and the tire on asphalt is just not spinning or spins so slowly that you can still see every spoke of your rims.
Just judging from that small test I’d say 100% is locked and 0% is open.
By the way, I had to test this after both you, and Bulin claimed it was other way around, just because it was completely other way around that I thought it is. Bulin I don’t know too well but I’m well aware how fast you are, and the few cars I have driven from you have been absolutely great.
Going back on the diff setups
On RWD (fm4) I tend to run almost non existing (below 20%) cause I get better corner exit with that setup, as if I happen to overpower 1 tire, other will still keep my rear on line. also it doesn’t restrict my turning, and I can keep fairly good power going up trough the corner.
In FM5 my diff setup varies the most from 20-50% range, but I’m still just getting a feel for the game as I got it just few months ago, and therefore I’m still trying to find what works for me.
The reason the front Diff can be set to lock so early is if you break the inside grip its basically going to be locked no matter what and the higher settings lead to less rpm bouncing. Its not as important on FWD because THE WHEELS ARE TURNED. So you don’t suffer handling penalties from a differential that locks too early generally because you can always turn such that your steering angle matches where you need to go. I’ll play with it from 30-100% on FWD 10% at a time to find where the rpms bounce around the least which I feel has alot to do with also the gearing and angle of the turn.
100% differential on accel means both tires spin which creates exit or on power oversteer
0% differential on accel means one tire spins which creates a push in the car
clairvoyant, you are wrong here.
Also, you can debate all you’d like but don’t troll and bait anymore. If you can’t have a discussion with others without insulting them or using metaphors to try and demean them then find yourself another forum to type on. It won’t be allowed here.
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Umm, that’s not really in discussion. What is in discussion is 100% = locked and 0% = open diff. Considering that the behavior you described corresponds to everything I’ve being saying, thank you for agreeing with me. As for trolling, I’m made multiple attempts to steer the conversation away from this topic and only posted one picture to describe my dismay when someone said (basically) that they refuse to be convinced no matter what evidence is given.
Once again let’s give an inventory. I made a casual correction of Bulin of the terms he was using to describe a diff. He said I was incorrect, which prompted my to verify my opinion in the game, post my findings here, then cross correlate those results with real world physics. None of those results were ever actually argued. They were simply deemed incorrect because I don’t have a #1 tune. Despite many claims otherwise that is not a counterargument. Most people are saying I’m wrong without even understanding my position and even AGREEING WITH IT (like yourself). It is not trolling or baiting to defend your position with in game testing, understanding of real world physics, personal experience with real world examples that correlate with in game examples, and video that does same, and then bowing out of the argument entirely when it is obvious that the opposition refuses to see any type of reason.
I said, “I will be bowing out of this conversations, unless specifically summoned, out of respect for Cool The Kid,” and I’m called a troll.
Roadrunner said, “That’s my opinion and to be honest, I don’t care if other people think I’m wrong, I’ve produced and set No.#1 times in all my own tunes so I have to be doing something right,” and is considered reasonable and should be respected just because he’s fast in a video game. …Hmm
Please elaborate on what you mean. What did I say, which for some reason makes you want to quote me, which was so insulting that you had to say that my post should not be “considered reasonable” and that you now think I “should be respected just because he’s fast in a video game,”, eh?
I stated fact that the times I have done which have gotten a No.#1 time are all in my own tunes. I simply said that “I don’t care if other people think I’m wrong,” why?
Well I quote “I have to be doing something right” - which is true otherwise I wouldn’t get those times.
And you think that’s unreasonable? I’m not allowed my opinion? Are you some type of dictator now? Gosh, people these days.
Firstly, I never said that you were wrong in terms of the ‘real world’ - just in terms of Forza. Yes, somethings that this game does interprets what you said, but certain aspects of the effects from the settings don’t correlate that well with the game - and well there we go, it’s just a game. A game which I like, and a game where I don’t need a dictator telling me how to tune thank you very much.
Have a ‘great’ day,
RR
You directly asked me what the percentages for the diff actually mean. I gave a direct quote from the game for what they mean. Previously, I’ve given information which confirms that Forza’s interpretation of the physics of a diff are correct (it would be very hard to make a driving game if they weren’t). You said that was incorrect, but really had nothing to base that on other than being fast in the game. You further said that you won’t be convinced otherwise unless under some very specific parameter’s (which have been filled by myself and other’s). I consider it very unreasonable for anyone to figure that they’re right just because they are and then say only this or that can convince me otherwise. It is not really a matter of opinion. I said…several DAYS ago that at 0% the diff is basically an “open diff” at 100% it is basically a “locked diff.” There are several behaviors associated with each in real life and elaborated by many here (including myself) to say that forza mimics the behavior of an open diff at 0% and a locked diff at 100%. There really is nothing more to be said on the topic, so if you want to keep talking about it shoot me a PM and we can stop muddying this thread.
To get the thread back on topic, let’s talk about the second part of your post which is tuning strategies. There are several different ways of getting it done, and while I’ve listed preferences, I’ve never said there is one best way. I personally prefer to make a very aggressive car that turns in quickly and can put power down on exit. They may not be the easiest cars to drive fast, but they are fun and can hold their own in a lobby (if it’s possible to separate driving skill from the car itself). It would help Cool the Kid if everyone listed their style and how they get there, and he can pick his preference. So RR, what’s your style?
Did I call you a troll? I said you were trolling in this thread but never stated you’re a troll. You were trolling and despite people leaving the thread you continued to bait people into the conversation and speak down to them. I won’t explain it again and I’d recommend not making a debate of it.
Next, you are never creating an open or closed differential in the game, it is an Electronic Limited Slip Differential, this is where you are wrong (and everyone else). All you are doing is controlling the torque output to the wheel in a limited slip condition and how independent one side is to the other. Moving the setting can start to represent one or the other in a specific condition but it’s never locked or closed. At 100% the outer wheel is going to be more prone to overtaking the inner wheel and create oversteer.
Everyone: Locked differential wheels always ROTATE at the same speed. Open differential wheels always get 50/50 of the torque but don’t rotate at the same speed when you start factoring in the weight, friction, etc. RR, Bulin, James…you guys are wrong in locked vs open but you are still correct in your description of how your adjustments effect a car.
Explained…it’s boring. Open vs Locked Differential - Torque Transfer - Explained - YouTube
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For CoolTheKid
Throttle control
High rebound (over 10.0) on both
Minimum bump
Soft springs, basically a 3rd of the bar making them even
Run roll bars at 5/5
I will give this a try. When you say rollbars at 5/5 what do you mean?