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The first two reviews on the M6 say the same thing regarding the handling: that the M6 will "...understeer when pushed hard...". I haven't read the same thing about the M5. Could this be due to the M6's front weight bias compared to the M5? I believe the M6 is 54/46 where the M5 is close to 50/50.
 

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Wolverine said:
The first two reviews on the M6 say the same thing regarding the handling: that the M6 will "...understeer when pushed hard...". I haven't read the same thing about the M5. Could this be due to the M6's front weight bias compared to the M5? I believe the M6 is 54/46 where the M5 is close to 50/50.
Understeering is not an error it is planned. Understeering is easier to handle for non racing drivers then oversteering. Allmost all modern cars have understeering only few sportscars have oversteering.

The M6 is heavy and thus the inertia is also high. Pushing it with so many power and weight they have decided to setup for understeering.

AM
 

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mumbasic said:
Understeering is not an error it is planned. Understeering is easier to handle for non racing drivers then oversteering. Allmost all modern cars have understeering only few sportscars have oversteering.

The M6 is heavy and thus the inertia is also high. Pushing it with so many power and weight they have decided to setup for understeering.

AM
Sorry, but having drive Audi's for 20 years I'll have to disagree with your first point. If a car has the majority of it's weight in the nose, understeer is inherent in the design. You can try to compensate for it, but a nose-heavy car will always have a tendency to understeer, it's just physics.

There are a number of ways to compensate for inherent understeer, mainly through suspension tuning. Oversteer (such as on a Porsche) can be compensated for simply by increasing the rear tire width. It's more difficult to compensate for understeer with tire width, since you don't want larger tires on the front wheels. Nobody 'plans' a car to be nose-heavy for good handling. It just sometimes is unavoidable.
 

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Wolverine said:
Sorry, but having drive Audi's for 20 years I'll have to disagree with your first point. If a car has the majority of it's weight in the nose, understeer is inherent in the design. You can try to compensate for it, but a nose-heavy car will always have a tendency to understeer, it's just physics.

There are a number of ways to compensate for inherent understeer, mainly through suspension tuning. Oversteer (such as on a Porsche) can be compensated for simply by increasing the rear tire width. It's more difficult to compensate for understeer with tire width, since you don't want larger tires on the front wheels. Nobody 'plans' a car to be nose-heavy for good handling. It just sometimes is unavoidable.
Hmmh, understeer is sure design. But old BMW did have a large front engine and oversteer. Ferrari has oversteer. Porsche has oversteer but they try to bring the car to neutral. The best way is that your car don´t have understeer and don´t have oversteer. Porsche is increasing the back tires to avoid oversteer.

What happed in the moment you get under or oversteer?
If you have a understeer the tires are loosing grip to go the desired direction and the car is going to the outside of the curve. If you have understeer the back tires are loosing traction (because you are pushing more power to the wheels then they are capable to bring to street) and the back of your car is going to the outside of the curve. What can you do to avoid understeer? You can use AWD, large tires or more weight on the back tires. What can you do with oversteer? Less weight of the car, less power, different weight distribution or stiffer setup. So you see understeer is harder to solve.

AM
 

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Wolverine said:
Sorry, but having drive Audi's for 20 years I'll have to disagree with your first point. If a car has the majority of it's weight in the nose, understeer is inherent in the design. You can try to compensate for it, but a nose-heavy car will always have a tendency to understeer, it's just physics.

Nobody 'plans' a car to be nose-heavy for good handling. It just sometimes is unavoidable.

You can't be compare AWD to RWD. You absolutely CAN dial understeer OUT of a nose heavy car. I race a Fox body mustang which is a very nose heavy, sloppy car. With my suspension set up this car is extremely neutral.

Now, my e39, which has almost 50/50 weight distribution, has by design understeer. All BMW's do. They do this for insurance reasons as was stated by mumbasic.

My E34 is more nueltral due to equal size tires than my E39.
 
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