看来Volvo, 包括新的XC-90的Haldex, 都是太公四驱, 每个后轮只有2.5%的扭矩 "The Volvo automatic AWD system has no traditional transfer case. Primary power goes to the front wheels. The rear drive shaft incorporates a viscous coupling (Haldex on the new XC-90) and as long as front and rear axles rotate at the same speed the coupling unit would remain inactive and the rear tires receive no torque - they are just rolling along. Would indeed slippage occur at the front wheels, the VC (Haldex) will create a power flow to the rear axle. But if only the front is powered in no slip situations (which is almost always) and the rear does not get any torque - how can Volvo claim it to be an AWD system? Surprisingly, if only one axle is powered, front and rear axles do not rotate at the same speed. The powered axle always spins a little faster ( about 5%) than the axle with the wheels just rolling along. It slips a little on the ground. So, the VC (now Haldex) reacts to the speed difference and compensates with a proportional allocation of torque for the rear. This way the rear axle will get 5% of the torque and thus each rear wheel receives 2.5%. Voila! All 4 wheels get power all the time. Volvo PR did not lie - it is full time AWD. However, a power distribution of 95/5 makes for very insufficient traction use. The front axle is very likely to start spinning with the slightest change of traction. A power split of about 50/50 guarantees the safest use of available traction. After all that's the way 4WD was intended to be. Volvo does not offer that."
【在 e******g 的大作中提到】 : 不是平时前驱,后轮打滑后才转么。跟ford edge和hyundai santa fe一个套路吧。
f*t
58 楼
你家的爬坡王能爬44楼里的坡吗?现在的subaru平时也是只把很少的动力传到后面。
viscous flow be
【在 e**n 的大作中提到】 : 看来Volvo, 包括新的XC-90的Haldex, 都是太公四驱, 每个后轮只有2.5%的扭矩 : "The Volvo automatic AWD system has no traditional transfer case. Primary : power goes to the front wheels. The rear drive shaft incorporates a viscous : coupling (Haldex on the new XC-90) and as long as front and rear axles : rotate at the same speed the coupling unit would remain inactive and the : rear tires receive no torque - they are just rolling along. Would indeed : slippage occur at the front wheels, the VC (Haldex) will create a power flow : to the rear axle. : But if only the front is powered in no slip situations (which is almost : always) and the rear does not get any torque - how can Volvo claim it to be
Y*a
59 楼
viscous flow be 真的假的? 这样的话,新Volov的AWD也太差了吧?
【在 e**n 的大作中提到】 : 看来Volvo, 包括新的XC-90的Haldex, 都是太公四驱, 每个后轮只有2.5%的扭矩 : "The Volvo automatic AWD system has no traditional transfer case. Primary : power goes to the front wheels. The rear drive shaft incorporates a viscous : coupling (Haldex on the new XC-90) and as long as front and rear axles : rotate at the same speed the coupling unit would remain inactive and the : rear tires receive no torque - they are just rolling along. Would indeed : slippage occur at the front wheels, the VC (Haldex) will create a power flow : to the rear axle. : But if only the front is powered in no slip situations (which is almost : always) and the rear does not get any torque - how can Volvo claim it to be
subaru 50:50分配动力的车之有六纲缸或手动版本,你的fxt和这个毫无关系,别自慰 了。 下面是关于AWD的评论: What is the best 4X4 or AWD system for snow weather? Cemtur Answered Last First of all, tyres (tires) are the nr 1 consideration when it's driving on ice and snow. Motor power or 4x4 drive systems are nr 2 consideration. I personally see that handling and grip of 2WD (two wheels drive) cars are not worse than any 4WD SUV when equipped with good snow tyres. I saw many examples that 2WD car with snow tyres climbs on icy hill where 4WD SUV slips because without snow tyres. Note that, not all winter tyres have good performance on snow and ice. Some winter tyres are very good on cold weather and rain, but some winter tyres give exceptional grip on ice and snow. Coming to your question of 4x4 systems, you need to choose between (terrain drivable) 4WD and (city drivable) AWD. Altought there are many sub categories and different implementation techniques of both, these are the main categories when choosing a vehicle. Simplifying the question: Are you driving mostly on off-road or mostly in city ? Simple explanation of 4WD and AWD systems: Basically, 4WD systems are mostly a mechanical center box distributing power to front and rear axels equally. There are versions of it, distributing percentage of power to required axels when slippage of one axle occurs. These systems are used on 'real' off-road trucks and vehicles. 4WD in general, and when coupled with electronic controls on each wheel is more robust and powerfull system for traction on mud or snow. But keep in mind that driving in asphalt, high speed turns and manuvering in the city kill 4WD mechanics and damage to tyres. They are "kill me or drive me mostly on terrain" systems. There are of course versions of 4WD making it more flexible for city use but in exchange of great traction capabilities. (Audi Q series are known examples of the worst modification to the 4WD system, check videos on youtube) AWD on the other hand is designed for mostly city drives. There is no center box, mostly electronic driven hydrolic clutches on rear and/or front axels distributes power as it is needed (computer decides!). May not be powerful as 4WD on terrain but certainly quicker in reaction. On the other hand pleasure to drive in city and on slight off-roads, no problem on high speed turns. It's also usefull on mud and snow. When driving AWD in off-road and very slippery conditions, you just need to know few techniques and must have off-road tyres, not high-performance city tyres! Most luxury SUV drivers fail on muddy terrain and then complain about AWD system, just because they drive with stock city-tires that comes with their vehicles! While, most 4WD terrain vehicles are sold with off-road tyres! That makes a lot of difference at first hand. Without proper ice&snow tires, all driving systems can fail in icy slippery roads! Example of vehicles using 4WD, mechanical lock: (mostly good traction on ice & snow) Land Rover Defender, Discovery Range Rover Jeep Grand Cherokee, Commander Ford Explorer, Expedition Mercedes GL, G Lexus RX300 Lincoln Navigator Mitsubishi Pajero Suzuki Grand Vitara, Escudo Subaru Toyota Land cruiser, highlinder, sequoia Example of vehicles using 4WD modified (Torsen differential) (mostly worst traction on ice & mud): Alfa Romeo Q4 series Audi A series Audi Q series Bentley Chevrolet Trailblazer Lexus GX470 Toyota 4runner, cruiser, hilux Example of vehicles using AWD (mostly acceptable traction on ice & mud): Audi A3, TT, R8 BMW X series Chevrolet Equinox Chrysler Pacifica Dodge Nitro, Caliber Ford Fusion, Escape Honda CR-V, HR-V Hyundai Santa-Fe, Tucson, Veracruz Infiniti G, M Land Rover Freelander 2 Mazda CX Mitsubishi Outlander Porsche 911 Subaru Legacy, Outback, Forester Suziki SX, XL Toyota RAV4 Volvo S, V, XC series ###### Today's most advanced and recent AWD system for me is the Halldex 4th generation which is used in Volvo XC60 and Saab models. ###### I have Volvo (Swedish) XC90 (AWD Halldex 2nd gen) and I use Nokian (Finnish) WR G2 (This is a good combination as both nation have to live with snow all the time, they design best snow tires & vehicles, IMHO!) My other choices would be BMW (German) X series or Mitsubishi (Japan), for tyres; Pirelli (Italian) scorpion ice&snow or Bridgestone (Japan) Blizzak.
【在 f****t 的大作中提到】 : : subaru 50:50分配动力的车之有六纲缸或手动版本,你的fxt和这个毫无关系,别自慰 : 了。 : 下面是关于AWD的评论: : What is the best 4X4 or AWD system for snow weather? : Cemtur : Answered Last : First of all, tyres (tires) are the nr 1 consideration when it's driving on : ice and snow. Motor power or 4x4 drive systems are nr 2 consideration. : I personally see that handling and grip of 2WD (two wheels drive) cars are
受不了你了, 都告诉你官网信息在这里了 http://www.subaru-global.com/tec_awd.html The Lineartronic CVT (Continuous Variable Transmission) uses a chain instead of a belt—allowing a greater span of overall ratios for improved performance and efficiency as well as a faster response to throttle input. The active torque-split AWD system usually distributes torque 60:40 front and rear, however sensors constantly monitor the vehicle's condition in areas such as changes in grip of the front and rear tyres or vehicle speed. The electronically controlled MP-T (Multi Plate Transfer) adjusts torque distribution to the front and rear tyres in real-time to suit driving conditions, as well as the transmission and driver inputs. This further increases the stability of the AWD system to deliver a safe and agile driving experience. 60:40 看见没有! 倒是你们要说说为什么新XC90 变成95:5 了。 这样说来,你的老XC90还不错呀,哈哈
【在 Y****a 的大作中提到】 : : 受不了你了, : 都告诉你官网信息在这里了 : http://www.subaru-global.com/tec_awd.html : The Lineartronic CVT (Continuous Variable Transmission) uses a chain instead : of a belt—allowing a greater span of overall ratios for improved : performance and efficiency as well as a faster response to throttle input. : The active torque-split AWD system usually distributes torque 60:40 front : and rear, however sensors constantly monitor the vehicle's condition in : areas such as changes in grip of the front and rear tyres or vehicle speed.
Y*a
76 楼
你看下面的评论 litesp33d1 year ago Almost brand new highest quality winter tyres. What is so difficult? 别人都不信。 另外,你这个人真是有毛病, 就算老XC90不错,也不等于suburu就不好。动不动就说“subaru的对称awd是彻底没了 ”,真是吃多了。 你们要劝别人买Volvo,就老实点,到处找茬树敌,只会让人反感,就算不买subaru, 也轮不到volvo。 建议还是去黑BBA或者LAI比较合适,那才是Volvo的对手车,天天跑来咬subaru,真是 太搞笑了,除非volvo不做豪华车了,否则volvo卖到下辈子都卖不过subaru的。
【在 Y****a 的大作中提到】 : : 你看下面的评论 : litesp33d1 year ago : Almost brand new highest quality winter tyres. What is so difficult? : 别人都不信。 : 另外,你这个人真是有毛病, : 就算老XC90不错,也不等于suburu就不好。动不动就说“subaru的对称awd是彻底没了 : ”,真是吃多了。 : 你们要劝别人买Volvo,就老实点,到处找茬树敌,只会让人反感,就算不买subaru, : 也轮不到volvo。