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> Snow tires makes more of a difference than being FWD or RWD in heavy conditions is the real truth here. A FWD with snow tires or chains will almost certainly

> Snow tires makes more of a difference than being FWD or RWD in heavy conditions is the real truth here. A FWD with snow tires or chains will almost certainly have better snow/ice handling than a RWD with snow tires or chains, by the simple virtue of the drive axle being steerable. If you've played Kerbal Space Program or a similar spaceflight simulator + rocket designer, then the reasoning here should be pretty intuitive: if you can only apply thrust to the reverse, and don't have reaction wheels, then in space you have no ability to steer under your own control. You need to be able to point thrust to the sides if you want to be able to turn (or stop turning). Same deal on an icy road. RWD means all your thrust is pointed backwards; FWD means you can point your thrust to the sides and control your car's orientation. Having both FWD and RWD (i.e. AWD or 4WD) is even better; sure, it constrains the overall thrust angles, but you also get more of it - which means better control when you're driving on a surface that ain't flat. This ain't just theoretical; it's something I've repeatedly observed every winter here in the Reno/Tahoe area.

m463 4y ago
> by the simple virtue of the drive axle being steerable. Is that a virtue? it makes steering tougher. The actual virtue is the weight of the motor over the front wheels (coefficient of friction * basically weight above tires)
- yellowapple 4y ago
  > Is that a virtue? it makes steering tougher. Not in my experience it doesn't. In icy or otherwise low-friction conditions, the steerable wheels being powered makes correcting for understeer and oversteer much easier than if they're unpowered - specifically because, per above, you can readily accelerate in directions other than forward/reverse, allowing you to orient the car even when sliding out. You can't rely on the tires' lateral friction to help you steer; a tire at an angle on ice will just slide with the rest of the car, and needs to be spinning to apply any force on said car other than forward. The catch, though, is that you have to be willing to accelerate at the very moment your brain would otherwise panic and tell your feet to hit the brakes. Hitting the brakes will make things considerably worse by stopping the spin on your tires (especially the fronts, which are the very tires for which spinning is absolutely essential for steering control). (In snow, this is a little bit less severe; the deeper the snow, the more pushback on the sides of the steering tires when at an angle, which helps a little bit with steering - but not nearly as much as on a dry road, thus still necessitating being able to accelerate with those tires) > The actual virtue is the weight of the motor over the front wheels (coefficient of friction * basically weight above tires) This also helps, but not nearly as much as the front wheels being able to accelerate in the direction they're pointed.

m463 4y ago

> by the simple virtue of the drive axle being steerable. Is that a virtue? it makes steering tougher. The actual virtue is the weight of the motor over the front wheels (coefficient of friction * basically weight above tires)

yellowapple 4y ago
> Is that a virtue? it makes steering tougher. Not in my experience it doesn't. In icy or otherwise low-friction conditions, the steerable wheels being powered makes correcting for understeer and oversteer much easier than if they're unpowered - specifically because, per above, you can readily accelerate in directions other than forward/reverse, allowing you to orient the car even when sliding out. You can't rely on the tires' lateral friction to help you steer; a tire at an angle on ice will just slide with the rest of the car, and needs to be spinning to apply any force on said car other than forward. The catch, though, is that you have to be willing to accelerate at the very moment your brain would otherwise panic and tell your feet to hit the brakes. Hitting the brakes will make things considerably worse by stopping the spin on your tires (especially the fronts, which are the very tires for which spinning is absolutely essential for steering control). (In snow, this is a little bit less severe; the deeper the snow, the more pushback on the sides of the steering tires when at an angle, which helps a little bit with steering - but not nearly as much as on a dry road, thus still necessitating being able to accelerate with those tires) > The actual virtue is the weight of the motor over the front wheels (coefficient of friction * basically weight above tires) This also helps, but not nearly as much as the front wheels being able to accelerate in the direction they're pointed.