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OK so I hear lots of smack about how the AWD system in the MS6 is FWD pretending to be AWD. However I swear I have teased power oversteer out of the car on several occasions.

Anyone else get power oversteer out of the MS6? Curious if there are any drift videos from Japan that show the car hanging the tail out with power on?

...Maybe I'm smoking crack? :goon:
 

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OK so I hear lots of smack about how the AWD system in the MS6 is FWD pretending to be AWD. However I swear I have teased power oversteer out of the car on several occasions.

Anyone else get power oversteer out of the MS6? Curious if there are any drift videos from Japan that show the car hanging the tail out with power on?

...Maybe I'm smoking crack? :goon:
[/b]
Step 1: find empty road or parking lot (rain would be better but dry can work too)
Step 2: turn off the DSC (button next to steering wheel)
Step 3: put the car in first start to move forward
Step 4: turn wheel to one side
Step 5: Smash accelerator to floor
Step 6: watch your back end slip out and enjoy the overeteer

:D
 

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OK so I hear lots of smack about how the AWD system in the MS6 is FWD pretending to be AWD. However I swear I have teased power oversteer out of the car on several occasions.

Anyone else get power oversteer out of the MS6? Curious if there are any drift videos from Japan that show the car hanging the tail out with power on?

...Maybe I'm smoking crack? :goon:
[/b]
Show me a car that dosent have oversteer Awd or not . Ya it does have some more so till the Awd comes on, But it just makes the ride that much more fun to get a lill tire spin to help this heavy pig out the hole.O Ya and it will drift when told to.
 

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Show me a car that dosent have oversteer Awd or not . Ya it does have some more so till the Awd comes on, But it just makes the ride that much more fun to get a lill tire spin to help this heavy pig out the hole.O Ya and it will drift when told to.
[/b]
Power oversteer is the key word here. I can get the rear to kick out when I apply power on the exit of a corner.
 

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Power oversteer is the key word here. I can get the rear to kick out when I apply power on the exit of a corner.
[/b]

The AWD system in the MS6 is unable to allow the front and rear wheels spin independently without some sort of binding action. It is a coupling and not a differential.

When the haldex coupling activates in a turn it tries to sync the front wheels which are moving faster to the rear wheels which are moving slower. Since more weight is on the front of the vehicle the rear wheels will loose traction first.

When you "romp" on it the haldex coupling tries to sync and destabalizes the rear of the car. By mechanical design the rear wheels will never receive more power than the front wheels.

Haldex couplings are FWD most of the time and actually transfer less torque the tighter the steering angle. The sharper the turn the less AWD. This is to prevent the speed diffrence between the 2 sets of wheels from destablizing the car. However you can still get it to happen by agressively stomping on the gas inducing a lock.

The power on oversteer has little to do with the torque delivered to the rear wheels but rather by the binding imparted by the engagement of the PTU.
 

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If all the tyres are the same diameter, how can the rear's possibly be moving (assume you mean rotating) slower than the front's?

When a car is turning the outside wheels have farther to travel and rotate faster than the inside wheels. Thats the only time wheels of the same diameter on the same car rotate at different rates, with the exception of power spin/brake slip.

And where do you get "the sharper the turn the less AWD"? Do you own a speed6, have you even driven one through all configurations? Or do you just read too much?

Lets get something straight, front wheel spin is not a prerequisite for transfering torque to the rear wheels. The system is active, not reactive. Given the type of driving I do my rear wheels are alive almost all of the time.
 

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It would take me forever to explain but it has been discussed before. I am well aware and have researched the basics of how a haldex system works and its shortcomings. If you have time to read the entire thread...

You will find that what I have stated is 100 percent true in order for a haldex system to work.


The basic shortcoming of haldex comes from the reason why cars need differentials in the first place...



http://forum.mazda6club.com/index.php?showtopic=50136&st=0




If all the tyres are the same diameter, how can the rear's possibly be moving (assume you mean rotating) slower than the front's?

When a car is turning the outside wheels have farther to travel and rotate faster than the inside wheels. Thats the only time wheels of the same diameter on the same car rotate at different rates, with the exception of power spin/brake slip.

And where do you get "the sharper the turn the less AWD"? Do you own a speed6, have you even driven one through all configurations? Or do you just read too much?

Lets get something straight, front wheel spin is not a prerequisite for transfering torque to the rear wheels. The system is active, not reactive. Given the type of driving I do my rear wheels are alive almost all of the time.
[/b]

Powering out of a turn if the haldex ever attempts to go full lock you will loop the car because it tries to sync the front and rear wheels together. Without diffrerentials the wheels cannot spin independently while still delivering power. Any amount of haldex lock will impart a syncing effect on the front and rear set of wheels which are spinning at diffrent rates.

All this more agressive haldex software is great... but the last place I want the haldex to lock up is when agressively powering out of an increasing radius turn causing me to completely loose it when my rear wheels which are spinning slower than the front wheels mid turn decide to match each other in speed at the limits of adhesion.

The more it locks the more it tries to sync the drivetrain together and force wheels spinning at diffrent rates to spin at the same rate. To prevent this it has to decouple partially if the computer detects a change in steering input. In performance situations, ie corner exit, hairpins, sweepers, it takes away AWD when you need it the most.

By definitition it can never be rear biased its just a clutchpack that takes power from the front and attempts to couple the front and rear wheels together.

Haldex can be defined as an automaticly acting part-time AWD system since it lacks a center diffrential.

To answer your question....

Visual aids...





Only when going straight all four wheels are turning at the same speed rate.

As soon as a turn is initiated all four wheels will rotate at different rates since each of them follows a different imaginary circle.
This is what happens during a turn:

The inside wheels will rotate with less rpm than the outside wheels.

The differential on the rear axle guarantees that the rpm delivered via drive shaft from the transfer case are distributed to the left and right wheel as needed. Meaning equal rpm when traveling straight - less rpm to the inside wheel and more rpm to the outside wheel when in a turn.

The differential of the front axle does exactly the same thing.

The axle differentials take care of the need for different wheel rpm.

Interestingly enough during a turn the front axle needs more rpm than the rear axle. Here is why:

The front inside wheel will need more rpm than the rear inside wheel.

The front outside wheel will need more rpm than the rear outside wheel.

This means that the front wheels need more rpm than the rear wheels in a turn

When you add the rpm of front wheels (A+B) you will find that the number is higher than the combined rpm of the rear wheels (C+D).

Unlike full time AWD with a differential - Part time "active" AWD is not able to accomodate the need for different axle speeds because it uses a Coupling or a PTU. To allow rotation the PTU must DECOUPLE reducing the amount of power delivered to the rear wheels.

Full time systems allow all 4 tires to push or pull at maximum rate. In part time active AWD this is not the case.
 

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"The more it locks the more it tries to sync the drivetrain together and force wheels spinning at diffrent rates to spin at the same rate. To prevent this it has to decouple partially if the computer detects a change in steering input. In performance situations, ie corner exit, hairpins, sweepers, it takes away AWD when you need it the most."

As much as I truely believe all this information, the fact of the matter is this, when you romp on the gas coming out of a corner (even at 30-40MPH) the car WILL oversteer... it just does it... end of story...
 

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"The more it locks the more it tries to sync the drivetrain together and force wheels spinning at diffrent rates to spin at the same rate. To prevent this it has to decouple partially if the computer detects a change in steering input. In performance situations, ie corner exit, hairpins, sweepers, it takes away AWD when you need it the most."

As much as I truely believe all this information, the fact of the matter is this, when you romp on the gas coming out of a corner (even at 30-40MPH) the car WILL oversteer... it just does it... end of story...
[/b]

You can get it to sync up with agressive input and destablaize the rear but its not because more torque is going back there its cause its binding the drivetrain. At the limit ANY diffrence in wheelspeed or upset in wheel rotation will get the rear end to come loose.
 

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As much as I truely believe all this information, the fact of the matter is this, when you romp on the gas coming out of a corner (even at 30-40MPH) the car WILL oversteer... it just does it... end of story...[/b]
I have to disagree with you here. Stretch and I actually went and test drove a MPS 6, just to see if this was true based on your claims. We did things with that car that would have shocked the salesman had he been in the car. The only time we got "power" oversteer, is if we first lifted (causing a weight shift to occur), THEN got back on the throttle. Merely turning the car while applying throttle resulted in it pushing quite hard away from the apex (Push = understeer). (Even at stupid cornering speeds).

However if you lift (even a momentary lift), the car tucks in very nicely, then you can apply some throttle to get the tail to wiggle some. (tucks like a standard 6 + rear sway)

The only time we were actually ever to get the tail to go out on it's own (without a weight shift occuring), was at extremely low speeds, in first, usually from a stop, or 5mph or less. (Exactly like strtfghtr's description)

I can't fully disagree of course, since I don't own the car, but it's not as if we are just reading and randomly commenting. We have driven the car for some good periods of time, on good roads, at cornering speeds too stupid to mention, trying to mimic claims and explanations of owners on the forum.

So I'd yes...yes the car can power oversteer, but it usually requires some sort of support to do so (weight shift). Purists will tend to call this "lift induced oversteer" instead of "power oversteer".
 
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