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AWD Drifting Technique - A Definitive Guide

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  • AWD Drifting Technique - A Definitive Guide

    Step 1 - finding that every single AWD system in the world is completely different from any other system...

    I drifted my AWD 91 Legacy Turbo for years, and it's no easy thing (IMO, harder than the RWD kind). My AWD was a viscous coupling type and not necessarily front-biased, there were things that I could do to hold the drift since the rear wheels were pretty much always getting power. However, in a front-biased system like the 4G63T's or CR-V’s, your rears will only get power when the fronts are slipping, as I'd imagine you know by now.

    Part of All-wheel-drifting is exactly what the name says: all of the wheels drift. If you watch AWD rally cars you don't usually see the front wheels following the "best line" on the course like RWD cars do (for the most part). A lot of the time the midpoint of an AWD car will be following the best line but the fronts and rears will all be spinning and the steering is toggled back and fourth between almost aimed straight and almost fully counter-steered. This coupled with the insanely high rates of entrance speed helps the car to stay sliding through the turn rather than grinding to a halt on the gravel, but high entry speeds also help keep the car sliding on pavement as well. Most of the time you won’t need to give as much steering input as you feel that you should after the initial “shock” of input to transfer the weight - sometimes only a third to half of a full counter-steer will be plenty to keep you sliding and a full steer will be too much and will whip you back around to the other side.

    Although AWD's purpose is to prevent cars from losing traction, you can really use it to your advantage to keep the wheels spinning. If you recall the "traction circle" that you learned in performance-driving kindergarten, you'll remember that the East and West directions represent steering right and left and the North and South directions represent acceleration and braking (respectively). Now, to make a car lose traction, the load on the tires must exceed their ability in any one of those directions or as a combination of two (or more, but that's a bit more advanced).

    Let's consider 2 cars with the same specifications, car A having RWD and car B having AWD. When accelerating from a standstill, car A will be sending 100% of the power to the rear wheels only. Granted that car A has the ability to load the tires beyond their capacity, it will break the traction circle and spin the rear wheels. If car B were to send 100% of its power to the driveline, it would momentarily go 100% to the front wheels (in the TSi's case) and break the traction circle causing wheel slippage. The slip sensor will detect this and tell the transmission to take up to 50% from the front and send it to the rear. (NOTE: The initial driving wheels and amount of power distribution will always depend on the AWD system in question) When it does this, the load on the front tires will move to inside the traction circle and the rear wheels' traction circle will look exactly like the front's (ignoring weight and transfer). Simple, right?

    Now imagine when a car is going around a turn and power is being applied while there is a constant lateral load on the traction circles of all tires on both cars, during a left turn for example (meaning that the work done on the tires is along the East-West line on the West side). While cornering at half of the capacity of the tires, car A can apply enough power to exceed the traction circle of the rear wheels (the work done by the tires is outside of the traction circle on the upper left side). Meanwhile, the front tires will stay at their half-capacity of lateral load without ever knowing what is happening to the rears. Once a driver counter steers, the direction of lateral load on the front tires is reversed (to the right in a left-turn drift) and they are now working to prevent the car from going off of the track to the left - there's a split second in a feint where the rear is sliding and the fronts are pointed straight just after the body roll has passed neutral. In our left turn, if the driver does a power-over and applies just enough power for the rears to break traction, he can keep the work asked of the tires just beyond the traction circle and maintain control of it, but if he applies too much power the tires will be overwhelmed and the driver will lose control -- this is why higher-powered drift cars need to have the power modulated in order to keep control and keep from spinning while lower power cars can be floored and stay in control.

    Ok, the same left turn example with car B and AWD. If the driver applies power in a turn, it may cause the front wheels to exceed the traction circle and transfer power to the rears, which in turn brings both front and rear back within the load limits of the tires, since half of the power is going to the front wheels and half to the back wheels. This would essentially be like driving car A in the same manner but with half the power at the driver's disposal (65hp for a Nissan 240SX, probably not enough to exceed even the stock tires). Even if your TSi has 200hp to the wheels, each set of wheels will see only half of that during a drift, and to get it to slide you either have to be turning harder or going faster to have the work exceed the capabilities of the tires (or use less-sticky tires).

    Unless you have tons of power, All-Wheel Drifting techniques require knowledge of vehicle dynamics, your drivetrain, your AWD system, and your traction circle (the best drivers are subliminally imagining all 4 traction circles of all 4 wheels all at the same time all the time). I find that the majority of the time all wheel drifting is spent trying to find ways to "trick" the computer into giving more power to the rear wheels than they can handle. Rocking the steering wheel between neutral and counter-steered one direction is a pretty good way to keep constant load on the outside tires and to find the best steering angle.

    You may also want to try doing a moment of very hard braking during the moment of the feint that has the front wheels pointed straight just before turn-in, and then applying maximum power through the apex. Try also varying this so that you don't feint but do sharp braking before the turn-in at a high enough rate of speed that the rear and will swing out, and then try a small steering angle while applying maximum power.

    Try getting up some speed (more than you think necessary) and cutting the wheel to one side and then counter steering with favor towards a small steering angle.

    You may be able to trick the AWD by pulsing the E-brake but not yanking it when you think the car is close to it’s lateral traction limit when approaching the apex. If you can, try to replicate the effect that rear-only ABS would have but make sure that you fully release before each pull - if your AWD computer is slow enough, it may see the braking moments as representing the “wheels that grip” and send power to those wheels with the power arriving at the rear axle just as you are releasing the brake pressure. Try this technique with the foot brake as well at various times through the turn, both with and without pressing the gas.

    I found that most of the operations in drifting an AWD car were pretty full on: full on the gas, full on the brake, etc. In racing they say that you should use smooth motions as to not upset the car's tenuous grip at the limit of traction, but in AWD drifting sometimes you will need to wrestle the car out of traction. Most of the time you will find that unsettling the car will be your best way to break traction while your manipulation of the AWD system will be your best way to maintain control.

    MOST IMPORTANTLY: BE SAFE!!! Don’t practice where you may run into something or someone or even where road surfaces are beyond an accepted level of safety. Don’t try and take on more than you feel confident with – drifting may be to-the-limit extreme, but that does not mean being stupid.

    Hope this helps and let us know how you make out!

    -MR

  • #2
    That was great, im getting my WRX soon and will definetly keep this in mind. I've heard that AWD does take more speed into a corner so there is enough momentum to carry the vehicle through.

    One major thing of this is the weight, and AWD car is generally 500-1000 lbs heavier than its RWD counterpartners. The 04 STi for example is close to 3200 lbs, most of it being the drivetrain.

    I've watched lots of rally and it seems the easiest way for AWD drifting would be to get a perfect suspension setup for soft in the front and hard in the rear. The advantage here is the weight transfer, make that front end light as heavy as possible. Hard braking before the corner, doing a feint motion, full throttle should easily get the rear to go out (or atleast make the rear tires loose traction). It seems, to drift AWD one would have to go beyond the "expected" limitations of drifting. For example, making the speed faster, harder braking like you said.

    Anyway, thats what I think of AWD drifting...

    Great info by the way, it was awsome.

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    • #3
      Thanks - it's been hanging around on my hard drive for almost a year, figured it was time to upload it all.

      If you're worried about weight, check the "weight reduction thread" in my signature. The "Braking Drift" thread is also aplicable for AWD drifting.

      Suspension setup is going to depend on the driver's preference - I had massive initial oversteer with a 24mm bar in the rear on my Legacy and the stock bar up front, with sustained neutral steer a tiny bit on the oversteer side.

      How far are you from Tampa? I could show you some things when you get your car if you are interested.

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      • #4
        Nice thread!

        Yep, AWD is a little different. It was something to get used to when I first got my Forester.

        I haven't really thought about the AWD system and how it initiates the AWD. Mines an '02 and I know it's the viscous type, but I don't know if it runs the front first then the rears. I know after the redesign for '03, they have a fuse in the engine bay you could remove to essentially make it a fwd car(disables the rwd). Mine doesn't have that. I'm thinking it just gives 50/50 and leaves it at that, not sure. I haven't really experienced anything to tell me different. Even on gravel from a stop, I don't notice the front or rear spinning alone. In fact it's quite hard to get the car to even spin its tires at all, even on gravel with pretty crappy tires, another testimate to the AWD requiring tons of power idea. One almost needs an STI to get enough power to freely light up all 4 tires.

        Good points too. They do like to be forced a little more. I think it's the whole trying to get all 4 wheels sliding idea. Mine's stock still, so I really don't do much for countersteering. I kind of have to actually steer into the corner to hold a slide under power, yay for understeer, lol. I plan to alieviate that problem in the near future.

        I'd also like to point out that all the off-throttle techniques still apply the same as with a rwd. Nothing changes in this respect...well except things like shift lock, clutch kick, and other things that affect the drivetrain since it now affects all 4 wheels. But braking, feint, e-brake and such all work the same way as a rwd.

        Things only start to change when you start giving a little gas. Thats when techniques need to change. Once you're on the throttle countersteering greatly diminishes, the gas pretty much stays on full throttle, and steering is then used to control drift angle. Throttle and braking modulation can still be used to adjust wieght balance and drift angle if needed.

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        • #5
          Awww, my first sticky Thanks mods!

          Food - The viscous type on your forester does drive the wheels 50/50 initially, which is why you probably get crappy gas mileage. The 5MT will vary power up to 80/20 or 20/80 depending on conditions and slippage. The 4EAT (Electronic Automatic Transmission) are 80/20 initial split and can go to 60/40 under slippage (with pre-96 models having a 90/10 initial split). Post-2000 models used all sorts of computer sensors to split power for optimum traction using clutch-packs, and also raised atf and clutch fluid pressure to maximum to give a faster reaction time.

          The AWD system is really good, so there won't be times where you'll notice that you're just spinning the fronts only unless you get ahold of a high-speed video camera. Drifting a stock AWD car can be really challenging because of this as well - usually in a drift the rears will be going faster than the front, enabling them to take a wider line, but in AWD all 4 wheels want to be going the same speed, which makes the car want to travel straight with power-understeer (as opposed to handling understeer).

          It's hard to say what exactly will be a good setup for AWD cars because all AWD systems are different. Even within in companies there may be several variations of a single system - my Legacy Turbo had a quite evident rear-biasment and slower reaction time than newer cars, which made it much easier to drift and "trick" into being RWD. The ATTESA ETS will deliver 100% power to the rear and transfer up to 30% to the front under slip with enough delay to momentarily burn the rear skins. Mitsubishi's AWD will drive 90/10 initially and transfer power up to a 60/40 split, but the rear drive lines on the DSM's is particuralrly weak (except for between 1990 and April 1991), making the EVO drivetrain a bit better as a starting point.

          Basically, getting some H&R springs with KYB AGX's and a 24mm rear sway bar from Cobb Tuning (for Subaru) will be a good starting point. Cusco makes all sorts of suspension parts for a bunch of different cars and will most likely have parts for a Forester (it's the same platform as an Impreza/WRX) or any other car you've got if you ask them.

          -MR

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          • #6
            I live in Orange Park, about 4 hours from Tampa, though I definetly am going to make it out to some of the drift days out there...

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            • #7
              awesome awesome awesome!

              It's been a few years since I've had any seat time in an AWD (hopefully to change soon) but like I said, I'd be happy to try and show you some stuff. There are some pretty talented drifters in Tampa who could most likely show you some stuff as well.

              DGtrials is looking to do a bunch more drift events in Tampa in the very near future, and in the short run there are people on tamparacing.com who you could probably meet up with.

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              • #8
                arigatou

                just wanted to say thanks to mranlet, lots of stuff you said i actually discovered on my own by trying it for myself. i actually drifted my first car by accident (and it came out good actually) and i just applied what i learned from a little mistake in the rain to my gsx. all i do pretty much is go fast, feint a turn, and counter and give it a lot of gas, and when i want to gain traction again, i just tap the brakes and steer it straight... i'm not so good with technical related things... but i wanted to say thanks again for posting this! i don't know when i can really go to a track and apply your principles, but its good to know...i live in tampa too! just holler if you wanna meet bro!

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                • #9
                  Originally posted by Miburo0721
                  just wanted to say thanks to mranlet, lots of stuff you said i actually discovered on my own by trying it for myself. i actually drifted my first car by accident (and it came out good actually) and i just applied what i learned from a little mistake in the rain to my gsx. all i do pretty much is go fast, feint a turn, and counter and give it a lot of gas, and when i want to gain traction again, i just tap the brakes and steer it straight... i'm not so good with technical related things... but i wanted to say thanks again for posting this! i don't know when i can really go to a track and apply your principles, but its good to know...i live in tampa too! just holler if you wanna meet bro!
                  I'm glad I could help! I just got a Legacy Wagon with no power, so it looks like I might be doing the RWD conversion until I can get a GT-B motor or something...

                  I'll PM you and we'll get together.

                  Comment


                  • #10
                    RWD conversion is complete, and aparently I have a Torsen diff from the factory :dunno:

                    AWD drift in this car was basically a battle against understeer - even pulling the E-brake caused understeer because it locked the center diff and acted like a weak form of the foot brake. I mostly had to initiate really late and feint, while clutch kicking right as you crossover from outside steer to inside steer.

                    Power always helps, and the stock Legacy motor has little of it

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                    • #11
                      wow...this is a great thread....ive been tryin awd drifts for couple years now...since my old 99 2.2 wagon...but now with my current car i havent been able to do much...though ive tried hard...but i have problem with findin a place with enough room where i dont hit anything....but this thread definatly helped!! ill go back out and try some of this....

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                      • #12
                        ..........
                        Last edited by atlantian; 02-15-2009, 03:59 PM. Reason: misspelt

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                        • #13
                          I've got a '99 Audi A4 and it's AWD. Just to make sure, cuz I read that all AWD systems are different. Will everything explained by mranlet work with the Audi too? Just some things I've heard makes me curious about this, and I want to see what the Audi can do besides slide around in the snow in winters like I always see on youtube videos.

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                          • #14
                            Drifting is drifting. The only difference between fwd, rwd, and awd of various systems is how it applies power delivery. All off-throttle techniques are the same. On-throttle techniques simply need to be tailored to how your system delivers power. Don't get too caught up what system you have, just understand how it works.

                            Also realize that a good goal for awd cars is a neutral balance. You want the car to rotate rather easily as understeer and pushing into corners will be what you will fight most. Once you get the car neutralled through suspension changes, you will find it very easy to drift, however, the style of drift will be different from, say, a rwd. Awd systems generally require a lot of power to break traction readily. Having a neutral setup helps considerably in getting the car to rotate freely and being able to toss the car around. The downside with low power is that you really have to drive the car right at the limit to get it to slide. You always seem to be closer to the limit driving an awd than a rwd.

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                            • #15
                              AWD Drifting Tech[nique] - A Difinitive Guide

                              hi all,

                              I've got a '99 Audi A4 and it's AWD. Just to make sure, cuz I read that all AWD systems are different.

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