Since we don’t really have a rally school or a testing area, we need to find a place that crams everything we need in a small space and loads fast. I might do a different guide for tarmac, but I wanted to stick with dirt since it’s so unwieldly. Looking at the image, we can test the following:
- Red: Chasis/Suspension settings
- Purple: Differential preload & off-throttle differential lock. Also for brake tuning.
- Blue: On-throttle differential settings and gearing
- Yellow: Gearing/Traction (same as on startup, but out of a corner).
- Green: Full speed braking.
If you’d like, go give the map a go and come back.
On the default setup:
- The car bounces around like crazy on the first straightaway.
- Bottoming out/bump steer on the first two jumps.
- On the big circle loop (Blue), there’s almost always a spin out 1/3 of the way in and the hairpin is always gnarly.
- The jump ditch combo sends you bouncing into the outside wall (last red section).
- At green, you’re overshooting the hairpin if you survived the straightaway.At this point, most of us say, “Ah well, I’ll just bounce through and still get a good run in ten tries.”
So for the first topic. On to brakes….
A good way to get brakes wrapped around our heads is downhill mountain biking. I like to set my rear brake so it will just start to skid on level ground and at any speed. I set my front brake all the way hard. Everyone’s different, it’s just the way I like to distribute the load.
When a vehicle enters braking in a straight line, the weight transfers to the front. The back end will not have the same grip as the front. On superbike races, you’ll see rows of guys braking (endoing) with their back wheels slightly in the air.
When a car is sliding sideways, it is a little more complex. You may want to downshift instead of using brakes to pull the car’s nose forward again (more on that in differentials). If you need more oversteer (do you really need it in this car?!) tap your parking brake and brace.
Anyways, I leave the brake distribution as is, because it already works great. I might as well not break it.
I have to admit, I have ABS set to 1 by default. I don’t want to keep switching the settings to get my OCD historicity down, so that’s where it’s at. I tested the brake force on the high speed straightway (pictured in green block) and couldn’t get the car to slide out with full brake.
This one should be pretty easy to explain, although there’s more to it than maximizing top speed in a stage. This area of the game is very subjective, as everyone races to a different style.
So for a little philosophy, being able to go from a stop to full speed for me is more important than squeezing out a higher top speed for a split moment. I prefer to accelerate out of a mistake than gain a few MPH at top speed (Colin McRash didn’t get a nickname for nothing). I tend to tweak towards acceleration so long as grip isn’t compromised.
One of the awesome things about the Stratos is that there’s wayyy too much power for the tiny little first gear they installed with the car. So I like to spread the power somewhere else (note how long first gear is in the image).
The above is my starting point. Notice how I curved (interpolated) the points to the same top speed (which I didn’t really hit on the long straightaway). As I get braver, I’ll tweak 1st back more until traction gets out of hand.
Did any of you run the RS200 for the daily event only to find it couldn’t climb out of 1st gear? Some of us were able to paddle shift up, but stacking the low end gears together would have helped.
Also remember that annoying downshift/upshift/downshift business in Greece? Run your gears closer together at the high end, so your little engine can squeeze top gear. As a general rule, you want to bias your gears together more for hillclimb stages and spread them out for descents.
- How does the car behave in 2nd around the loop? The hairpin? (See Blue zones).
- Take care not to run your gears too short, or you’ll end up locking up the back end when engine braking. Engine braking is one of the shining qualities of the Stratos. More on that when we get to differentials.
- Gamepad users: Try setting your acceleration lower on the bottom end to improve traction.
If you go into your Profile settings, you’ll find different transmission choices. You can chose any that you want, but if you’re looking at scoring top ten in the Dailies, you will want to go with Manual Sequential for the following reasons:
- Downshifting, in addition to braking, will slow your car way down. In many cases, such as in a properly setup Stratos, it will improve stability by a long shot.
- You can better control your RPM levels. For turboed cars, having your boost go to zero at a hairpin is not good.
- If you’re pushing too hard, you can stick to a gear to keep you honest. That way you’re not letting momentum get out of control.
Practice a full day or two and you’ll never go back. For X360 users, use your X & A buttons to shift.
Soo, you go do your first oil change and spin one of the tires. “Uh, why is the other wheel spinning the wrong way? Is it busted?”
Before you get started, if you want, check out this great video on (L)imited (S)lip (D)iffs:
So when it comes to codemasters implementing the idea of power transfer and suspension, I’m not quite sure what formula they use to simplify things like backlash, preload, friction, tire traction, etc.
The only thing we’re given is a term, a slider, and we drive the car. Here’s a rather extreme setup I liked, but you may want to go differently.
What makes it even more confusing is that the vehicle’s power distribution doesn’t really seem to change if you leave it low or max it out the opposite way. Almost feels like a placebo effect more than anything. There may also be a reason for it, as we’ll see below.
The Stratos, like other RWDs, is already very unstable with power on loose surfaces. Let’s pretend we weld the back axle together, so both wheels spin at the same speed (or setting your driving lock at 100%). As soon as we begin a turn, the wheels will break traction immediately. We don’t even need to apply gas, it’s a done deal. Since the worst handling for the stratos under power is in the tight corners, you might say, “Why not loosen the lock all the way?”.
Let’s look at situation below….
LSD’s try to place power to the wheel with best grip. In the above example, most of the traction is on the outside wheels. If your ride height is set high and road camber is bad, you may have no traction on your inside wheels (you start to flip). If all of the power is set to the outside wheel, the loss of traction might come off as unpredictable. Some drivers want to get all of the power to that wheel, some want more stability and predictability at the cost of power to that wheel. It’s down to personal taste.
One of the nasty side effects of Limited Slip Diffs for any car is when you have two wheels on the track and two off. When under power, your grippier wheel(s) will try to throttle steer you into the ditch.
To get the best of both worlds, you might want to leave the setting where Codemasters had it.
- On the large arc turn (Blue), you should be able to drive a smooth powerslide the entire way around. Try a smooth, low-powered Scandinavian flick through the tight hairpin on exit.
- Check to see if your car steps out (skids) down the camber on a slanted hill. In theory, when the setting is set to low lock, most of the power will go to the wheel with most traction (downhill side) or the outside wheel on a turn.
The second slider is our friend, because it acts to mesh the wheels smoothly together when we let off the gas -helping to straighten the car. It’s like when a tow truck pulls you out of a ditch…you straighten out, then roll. Some cars with open diffs will step out bad as soon as you let go of the gas. They call it trailing throttle oversteer (you really notice it on Pike’s Peak if you don’t feather the throttle back down).
To fine tune your coast setting, I use the purple section of the map (see below).
When you hit the red dot at high speed, you are forced to let go of the gas and also turn. If you feel the back end breaks out too unpredictably or too soon under braking or coasting, this setting and the preload setting may help, though again, I didn’t notice much difference. One of the best features of the Stratos (in this game) is the engine braking. Also test your brake balance in this zone. I found the default works really well. Try it in smoother high speed sections as well. If you haven’t tweaked your suspension from default, you might still be bouncing around.
As for the LSD preload, I left it alone, since I wasn’t experiencing any extra problems during coasting (When without torque).
Remember that if your gearing is set too far to acceleration (tight together to the left), you might break the back wheels loose from too much engine braking. Your differential settings may affect this behavior.
Guess what, FWD behaves totally differently. 4WD’s have two more differentials to deal with. That’s why this is probably a good start.
For gamepads and hardcore keyboarders, you may want to maximize stability in the high speed areas rather than in the corners, so tightening up the Power Ramp lock might help.
I’ll add again, that this may not match the real world. This is just a sim, and like tarmac in RBR, certain things had to be done backwards to get the same results.
Off to suspension and springs…
First off, I’ll just say that there’s enough drama packed in suspension and damping just even mentioning it. Trying to explain the real thing is one thing, unpacking what Codies synthesized is another.
- Do you want tight handling through the winding sections of hard-packed clay in the trees -like it was Monte Carlo?
- Do you want your car to effortlessly float through the jump/ditch combo and all those bumps at the beginning of the stage?
You have to chose one or the other…or something in between. I swerve to the latter for the following reasons:
- I race for clean runs and consistency, not the bouncing luck and replay button.
- I want to maximize my use of the track, not just hang in the center or on the lines that are imprinted on the gravel.
Regardless of your style on this particular stage, I want maximum contact with the ground at all times, so the power goes where it counts. This stage is rather extreme in that it has big jumps and ditches.
Ride height affects all kinds of stuff in the real world such as bump steer, wheel geometry, etc. All those things are important, but probably do not pertain to the Dirt world. What they did tell us is that it does affect suspension travel and that it might adversely give the car a high CG (center of gravity). This setting sets the baseline for everything else and thus may have the greatest impact on handling for any particular track.
Ride height needs to be set with the whole car. Codemasters chose to set the back end a lot lower. Usually the back end is set higher, so I’m not sure as for what reason. For myself, I used a more standard setup with the front end at default and the back end maxed out.
When it comes to springs, every car will have its own natural frequency. When highway driving, you’ll see cars that have no dampers (shocks) bounce up and down forever after a bump. This happens not only because of the springs, but as a function of the tires & their pressure as well (they act as an added spring). In the high end racing world, they’ll check setups to different frequency and amplitude rates. I was able to watch my car go through a test one time (not for racing) and you could see rates which didn’t cope so well. The wheel/suspension would react harmonically and move around more. This is a little over the top though, and for a different discussion.
For tuning suspensions at a given weight you have to gauge your stage, set ride height, match your spring to your tire (which we don’t do here), then set your main damper settings, then your fast settings. It all goes downhill from there.
So to simplify this a little, given that Codemaster’s physics engine (though excellent) may not really account for all these details, we can make some rough assumptions:
- For Monte Carlo, we want to set Ride Height low and Spring Rate firm.
- For Bidno Moorland, we want to set Ride Height high and Spring Rate soft.
So does that mean we can crank the spring rate to the bottom for a nasty rocky stage? Not exactly.
Off to part II…
Ever seen kids driving through a nasty ditch intersection, bottom out their car (with dampers already gone), and get 12 inches of air on rebound? We’re talking Crown Vics and Buicks, not little rally cars.
The spring’s job is not to dampen the impact, its job is to store the energy, so we can put it somewhere else (the damper, etc). If you receive more energy than the spring can store, such as in a hard landing, your car will bottom out and spike even more dramatically back into the air. This is what happens if your spring is either too soft (your bump stops hit) or too hard (spring acts like a bump stop).
For this stage, I have it set somewhere around the middle for both front and back sets. The idea is to find the threshold at any given stage just below your bottom-out point -for the most critical moments in the stage.
I left the below settings at their default levels. Tweaking these for tarmac would definitely come handy for increasing responsiveness.
I’m not quite sure how it’s modelled in Dirt, but in practice, roll bars are there to reduce chassis roll and transfer force from the inside tire to the outer (in a turn). If made too stiff, the inside wheel will loose grip, such as when exiting a turn at high speed. I left both settings at default. Remember too that if you set your differential very loose (power to outside wheel) and crank your sway bar tight (stiff), you may now have two factors working against your outside wheel grip.
For a real world example, check out this shot I took at the Botswana desert race. The front inside wheel has zero traction.
Think of how you might improve tuning based on this shot (note how stiff the front end is and how the back end (opposite to the front left wheel) is set too soft. A car will not only pivot front and back, but also corner to corner.
I left these alone. I was able to get increased stability around corners by maxing out negative toe angle on the rear axle, but it seemed to go crazy on the straightaway as soon as a wheel went airborne.
Off to dampers…
Dampers are the magic sauce to completing your setup and are the focus of a lot of attention.
While springs will determine the distance the suspension will travel and be matched to store the energy to be absorbed and released, dampers will do the following:
- Modify the “RATE” that the energy is stored under normal turning G-Forces. Called Bump.
- Modify the “RATE” that the energy is released under normal turning G-Forces. Called Rebound.
- Modify the “RATE” that the energy is stored under high velocity impacts. Fast Bump.
- Modify the “RATE” that the energy is released under high velocity impacts. Fast Rebound.
- Allow threshold control between bypass and normal modes (explained below).
Think of a damper as a syringe filled with hydraulic fluid and your thumb is the wheel. At a certain point, it doesn’t matter how hard you squeeze, your rate will be roughly dictated by the orifice or tip where the fluid leaves. If you want to get the fluid out faster, you open the hole up. Congratulations, you have now “ported” your damper and adjusted your “bump” setting to softer.
For stages with high-speed, winding turns like Pikes, you want your rates to be firm/slow. You don’t want your suspension to sag unpredictably fast to one side -sending you oversteering off track. When letting off or gunning the throttle, you want your springs tight and dampers moving things slowly under the twitchy environment.
Winding, low speed gravel is another matter though. The car needs to use its travel (which you have hopefully already set up with ride height and springs) to manage constantly changing camber and you want the car to keep the wheels moving up and down while the chassis is relatively stationary (hint: higher rate, faster fluid flow, softer settings). The following pic is a nice example of good articulation.
Without getting into too much detail, a damper not only can control the rate the fluid leaves the chamber (high speed turn entry) but also how fast it’s allowed to return and refill (turn exit). Return force (not rate) is determined by the following:
- Your main spring/helper spring pushing back down.
- Weight of your wheel
- Other factors such as damper gas preload.
If your wheel is allowed to return too fast, your springs (or worse, your bottomed out chassis) may be allowed to return at high velocity before you clear your smooth hill, sending you flying instead of going “through” the hill. You want to keep your springs under control.
Conversely, if your rebound is set too firm (slow fluid return back, slow rate, etc). Your wheel will not contact the ground after you pass the crest of your hill and you’ll find yourself spinning air guitar instead of shredding dirt.
Think of this as by-pass mode for all your rocks and bumps. Back to the syringe, let’s say we frequently burst the chamber from overpressurization (hit a rock). So we add a safety valve that opens ONLY when the pressure spikes past a certain internal pressure. Remember that even though the rate which the fluid flows through the main nozzle is about the same, the internal pressure in the chamber will continue to increase as we add more force.
When this special bypass valve opens, all of the sudden the syringe moves faster, because now we have two ports open instead of one and more flow (more RATE).
The same goes when we hit a rock. The damper goes into bypass mode because of the major pressure spike, allowing much higher flowrate from the additional orifice (less resistance to flow, the wheel comes up faster). This is a simplification of real world setups using shim stacks and a nitrogen cylinder.
Think of the “Fast Bump Threshold” setting as the minimum pressure required to go into bypass mode. That’s what will open the bypass valve. The “size” of the valve/port is your Fast Bump setting. It will determine how fast the fluid will move.
Remember that the threshold setting only controls WHEN the valve opens, the fast bump controls rate AFTER the valve opens.
In practical terms, you do not want the threshold to open during your normal turns. You want it to turn on ONLY when you hit the rock, bump, or jump…otherwise all sorts of unpredicable stuff will happen to your handling. It might feel as if your suspension is fading.
The fast rebound and fast rebound threshold work the same way as your normal rebound, except instead of dialing it in for large rolling hills and camber, you are tuning for rocks and jumps to be expected on the track. The goal of this setting is to maintain maximum wheel contact with the ground after sharp impacts and ripples in the road. If the wheel takes too long to hit the road, you’ll find yourself loosing precious time not applying power to the ground.
I really like using Bidno Moorland for this, because we have nasty ripples at the start that will skip you off the stage, two jumps, a jump/ditch combo, and finally a fast turning straightaway. I want to be able to consistently hit all four of those zones flat out at full throttle with only smooth wheel movements. You should tune the fast bump/fast rebound settings in these areas.
For bump and rebound, use the nice, rolling high speed straightaway at the top of the butte halfway through the stage. You still may want to keep these fairly soft as you may need some give from mistakes.
My settings may look as if I just picked a spot and lined them up, but I tuned each one where I liked it the most. Codies left what seems like a bug on the thresholds, because they don’t stay where I leave em. It might bid well to leave them as is though.
*For gamepad users, try setting your suspension to run a bit sloppier(soft/mushy) so you can focus more on setting good lines rather than constantly correcting for sharp bumps and rocks. It may also make the Stratos a bit less twitchy under acceleration on rough ground.
If things go way wrong, try starting over with a clean default setup. Race it for a while, then start tweaking again. Then race default again to check if you’re just fooling yourself (or in my case others).
Chocoloco, who has very good Stratos times in the rankings, wrote a nice thread for his Greece setup here.
This setup is much twitchier and difficult to drive, but if you’re on top and a little lucky through the bounces, you get faster times. Something to note are the camber/toe settings. Here’s my run below:
A plowed road with wet snow will have really bad understeer downhill, some days studs and your fancy AWD won’t save you. Just ask the 5 people my neighbor pulled out in one evening that DNF’d at the hairpin by my house. 🙂
That said, I’m taking the worst case scenario stage, Col de Turini – Sprint en descente for the test run. It starts really bad, but the one thing in our favor is flatness.
For tarmac, especially the smoother kind, I stiffen up my suspension/damping, tighten up the roll bars, then ratchet it up some more until it gets on the chattery edge of control. Here’s a zoomed out setup I like:
I also set the ride height as low as I dare, so that we’re not rolling like my Lancer from CMR05.
That’s pretty straightforward stuff, but it gets tricky when we start talking about stability on slick, flat ground. Here’s an oddball setup I liked for the rear suspension:
The Stratos is pretty decent to control from the rear end on tarmac, but the cornering on the downhill snow is horrendous. We didn’t really talk about camber and toe earlier, so I’ll jump in here.
When you drive with one hand on the wheel, the car is difficult to control. With two hands on the wheel pulling their weight down slightly, you have more stability. Fixed wing aircraft have dihedral (wing tips are higher relative to the wing roots) that creates stability. Helicopters have a cone angle under aerodynamic load that generates stability. Think of a ball in a bowl right side up instead of upside down.
In the same way, having your wheels slightly oppose each other creates certain stabilizing/destabilizing features which you might want (or a train wreck waiting to happen). In this case negative camber seemed to help with cornering grip as suggested by the Codies.
I left the toe angle alone simply because tarmac has a tendency to bite hard. If one of your two wheels -which are opposing each other on the flat road- leaves the ground, the other will pull the car in the direction it is “toed”. This is smoothed out nicely in gravel, like in the Greece setup above, but I couldn’t get good results on the grippy surface further down.
Much of this is coming out of my imagination, but we’re talking rally sims -where we make stuff up and tinker until we feel good about ourselves.
FWD’s are great for winter driving in the mountains. I had one with studded tires that could out-climb my old open diff Yota pickup. It was also understeer city and quite boring to drive.
FWD’s will straighten the car when under power, like pulling a cart by a string. In contrast, the Stratos is more like pushing the cart with a stick.
For us it is a problem, because even though the wheels are pointing towards the turn, the front wheels have less grip because of forces being imposed by the engine. This is true for both acceleration and deceleration.
I personally haven’t spent much time improving setups for FWD’s in game but these are some ideas I have that might improve handling:
- Too much brake bias towards the front + engine braking may induce movements similar to the Stratos throttle dance.
- Offsetting suspension stiffness/damping front to back to improve left-foot braking and acceleration characteristics during turns.
- Try messing with the front differential settings for improved cornering.
- Keep practicing Scandinavian flicks. 🙂
To be honest, I’d rather wait for future updates and cars, as I noticed no difference in the Mini’s times for Bidno using extreme diff/chassis settings.
4WDs combine the pros of RWD and FWD into one package. The trick is getting the balance we want for a particular stage. The front wheels (as a set) will also turn at different speeds relative the rear wheels. A center differential is once again needed to keep you from destroying your gearbox/driveshafts and for maintaining optimal grip. Remember that any time a turn is made, every single wheel will rotate at different speeds. If you forget to turn off the front locks on hard pavement on some 4WDs, you’ll hear your tires squealing at you in rage when turning.
It’s important to note, power comes out the engine to the center diff, then gets distributed appropriately to the forward and rear diffs.
If you set your favorite camping chair on an incline and sit down, most of the weight is going to be on the downward-most legs. When you’re carrying a washer into your basement, the guy helping at the bottom is carrying 75% of the weight. In the same way, a hillclimb car that is going up a hill and accelerating, will have most of its weight down on the rear wheels. If you check the hillclimb car presets (look inside the center visc setting), they’ve made the vehicles almost completely RWD for this very reason.
Engine oil will have the viscocity of nylon under crankshaft bearing pressures. Certain fluids are designed to solidify when exposed to shear or contact forces, so they can perform a certain function. Without going into detail, a viscous diff will send power to the front or the back diffs -the ones exhibiting the most grip. It can make the decision aggressively (all power to one side or the other) or only slightly (most power evenly distributed). That’s where the “Loose/Strong” setting comes in. Strong means that almost all the power will go to both ends of the car, even with changes in grip.
That’s regarding changes in grip, but can we change the percentage of power distribution under any condition? That’s what the torque bias setting does. This will give you the most obvious results and will make all your FWD/RWD hybridizing dreams come true. The description from Codies is self explanatory.
I like to bias my Group B Quattro a little more to the rear than stock (shown above). It makes the experience more frightening.
Here are some references I used to compile some of the info, which might come handy for you as well (and that made me sound like I knew what I was talking about).
RaceCarTuner.com Suspension Cheat Sheet[www.racecartuner.com]