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The topic came up today in the office about the effect of the snow and the pro's and cons of FWD RWD and 4*4. I was really surprised at the lack of knowledge especially a BMW owner who had no idea hers was RWD and a CRV owner who said his was FWD only. Now while 99% of the time it makes no difference to the average motorist driving in normal conditions, surely its key in this weather. If this basic lack of knowledge is common then it might explain some of the difficulties people get into for example stopping with their driven wheels in the icy gutter when exiting a drive or not allowing for another car having less grip than theirs if you are one of the 4*4 drivers who apparently doesn't know he's got it. I suspect its all part of people just trusting to the technology and letting the car and electronics do the work rather than "driving" in its fullest sense.
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It's quite funny really that BMW and Mercedes still persist with RWD given the extra cost and difficulties in packaging and safety when many of their drivers haven't a clue what wheels are driven and wouldn't use the extra dry handling abilities anyway.
No wonder Audi don't bother.
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Having had both FWD Audis and RWD BMWs I know which I prefer, you can certainly tell the difference - at least with more powerful variants anyhow.
Not sure there's extra expense in RWD, I thought that FWD took so long to catch on (after the Citroen Traction Avant in the 1930s and slightly earlier Alvis) precisely because it's actually harder to package and engineer. Most if not all FWD Audis actually still have the packaging disadvantage of a transmission tunnel due to their quattro option.
Aren't CRV's FWD most of the time with occasional AWD when required ?
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and a CRV owner who said his was FWD only.
Some CR-V models are FWD only.
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Wasn't that the HR-V?
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I know my 335d is rear-wheel drive, as are most BMWs. The reason they persist, despite the "difficulties", is that you can only put so much power through the front wheels before you lose the ability to control it (look at how much technology goes into the Focus RS to control 300bhp - RevoKnuckle suspension, ESP, Quiafe LSD), yet it still suffers from a degree of torque-steer. That's why you don't see any FWD supercars.
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(look at how much technology goes into the Focus RS to control 300bhp
What do they do in FWD Touring Cars, which IIRC are also about 300bhp, or don't they bother?
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CRVs are FWD until the front wheels slip at which point 4WD kicks in. Strikes me as bizarre... I watched one over Christmas trying to get up a slope. He wellied it, the front wheels spun, the car wobbled, the front wheels stopped spinning and suddenly all four were gripping and he moved forward.
Must be bizarre to drive.
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The difficulties in packaging I refer to with RWD are of course that because of the orientation of the engine, it is much harder to retain interior space to the required standards, and to do well on the front end testing of EuroNCAP. Witness the problems with the current 5-series with these tests.
Yes you can only get so much power through FWD, but given that 95% of BMWs are sub 200bhp 2.0 diesels, I can't see that being so much of a big deal. They could always use AWD like other manufacturers for the more powerful models, as Audi, Volvo and others do.
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I don't want to be pedantic but Audis (A3 excepted) have a longitudinal engine layout and front/rear transmission tunnel, engineering the bodyshells to support quattro gives the packaging 'disadvantage' of RWD, so were BMW to adopt it I can't see what advantages would be gained ?
I drove a 170PS / 256lbft FWD Audi A4 (so sub 200PS in your example) and now drive a RWD 245PS 385lbft BMW 3 and you can tell the difference between FWD and RWD in many circumstances I assure you. The Audi was marginally better in snow but it suffered torque steer even on relatively gentle acceleration, the BMW steers and handles much better.
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Yeah, I know all about the Audi silliness, all of the disadvantages of a longitudinal layout without the advantages of RWD! IIRC it's been discussed here a few times.
I don't doubt that all the above average drivers here (after all, why would Mr Average Driver visit HJ?) can tell the difference with RWD, I know I can, but a) is it that important and b) can Mr Average Driver tell the difference?
a) possibly not, depending on personal preferences and b) almost certainly not, as evidenced by the first post!
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can Mr Average Driver tell the difference?
Probably not, they are buying their BMW based on reputation, image, prestige however wrong or right that is, not on the fact that you can tell that the cars handling is better or it has a lack of torque steer. They are enthusiasts cars. That should be the reason you are buying it, but we all know that it doesn't work like that.
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(re: CR-V) Ahh - suspect I was looking at a USA-spec website where they definitely have a current 2WD-only model. Maybe they are all 4WD here.
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All 4WD in the UK - I would struggle to imagine why one would want one in 2wd only. Driving a CRV isn't any different to any other car or SUV, the change to 4WD is un-detectable - just vast amounts of grip when needed - OK it's not a Defender, but mine has been superb this winter. The driver you mist have seen must have been a leaden footed clod-hopper - hope he never fancies a BMW then.
Edited by Pugugly on 13/01/2010 at 12:24
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a BMW owner who had no idea hers was RWD
That explains lack of knowledge ;-)
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QQ has a similar setup. You can select 2wd or auto 4wd which only kicks in if the front loses traction or you can select locked 4wd. When combined with an automatic gearbox I've found the auto 4wd to be the best. If you leave it in permanent 4wd you can create a scenario where the front wheels start to lose braking force but the back ones are still pushing. In the auto 4wd mode no power is going to the back under braking if you don't want it. It has been faultless in this snow even on its standard Bridgestone Duellers.
Having said that, it has been no more or less than a convenience. The other two cars we use are fwd only and while they don't compare on grip neither of them have actually got stuck.
Fed up with this weather now though....
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If you really want to put the cat among the pigeons and get people scratching their heads, seek out one of the rare 2WD Land Rover SWB's and get it stuck somewhere!
Several hundred were made, some Series 1 and some Series 2. They were made for the RAF for road use and airfield runabouts, but with high parts commonality with standard 4x4 land Rovers.
Edited by Sofa Spud on 13/01/2010 at 13:16
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BTCC regulations limit engine power to approximately 300bhp and yes, the FWD cars do suffer from torque-steer. It's just that the drivers know how to cope with. Slick tyres also help.
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He seems to be managing all right with RWD:
i151.photobucket.com/albums/s138/Cliffordpope/240i...g
But then he's Swedish.
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Check out his tyres, they look like they're off a Land Rover. And it appears he's got some ballast in the boot, to open up an old wound............
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BTCC regulations
thanks for the info Andy
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