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Acura, Infiniti, Volvo
#54 of 96 Re: Some interesting AWD comparison on YouTube... [circlew]
Mar 19, 2007 (1:32 pm)
Habitat will likely tell you he prefers the lighter RWD version to the heavier, but more stable AWD version in the 355 hp 911S. The C2S is definitely quicker than the C4S off the line - I'd peg the difference as about the same as the difference betewwn a base 911 and an "S" version. Meaning that a base C2 is about as quick off the line as a C4S.
Now as a 2007 911 Turbo owner, you would think I would be a fan of AWD. True enough, in the Turbo, it is almost a necessity in order to put all of that power to the pavement without stripping all the rubber off your tires.
...But, I drove a RWD GT3 last week in Germany and fell in love. Probably not enough to ditch my blisteringly fast 911 Turbo and it's more civilized interior / ride. But there is no 911 that handles like the GT3. And with it's non-turbo 8,400 rpm redline, it is an absolute hoot to drive.
Forget the "wide booty" thing. The difference is not that noticable. Get a C2S or C4S - or a GT3 or Turbo - based upon what you will enjoy driving for the conditions you will be driving in. As much as I like my Turbo and the PASM button that switches the suspension between normal and sport settings, it would be sheer nirvana if I had a button that could toggle between AWD and RWD, with a way to ditch 300-400 lbs for the latter.
Mar 23, 2007 (2:15 pm)
Someone was asking for a Subaru person?
Subaru's system is not the most advanced, but it is simple, strong and effective. It's not intended to be used off-road (or on the beach). It's on gravel roads and snow it really works well. Unlike reactive systems most Subaru's send power to all wheels all the time. This means that you can take advantage of the AWD at higher speeds, which is why so many rally people use Subaru's. And I'm not just talking about high-dollar performance rallying; I'm talking about the grassroots navigational rallies and rallyX events that people enter with their daily drivers. Check out the entry list of any of your local rally events and you'll find probably half the cars entered are Subaru's. I've yet to see a SH-AWD Acura signed up (perhaps they're too new).
The Audi torsen system and the Mitsubishi Evo system are probably the only systems that work as well or (arguably) better in a reasonably priced car, but then Subaru's also have other advantages like better balance, lower center-of-gravity, interchangable parts and overall price.
If you want an AWD luxury car get an Audi or BWM. If you want to go off-roading get a Jeep. If you enjoy driving on twisty backroads get a Subaru.
Mar 23, 2007 (3:06 pm)
I'll toss in a vote for SH-AWD.
Other systems can route power from left to right, but they do so "reactively" and accomplish the task by braking the wheels. To date, Acura's AWD is the only one steering the car by overdriving the outside wheel. Audi and others have openly admired the torque vectoring properties of SH-AWD and are actively developing their own systems.
Somewhere in earlier posts, I read a few remarking that SH-AWD doesn't distribute all that much power to the rear. We might as well correct that.
Depending on the vehicle, the default torque split for SH-AWD is either 70/30 (RL) or 90/10 (MDX and RDX). That is how power is split when cruising.
When you stomp on the gas from a standing start, power is split between 60/40 and 50/50. It varies from vehicle to vehicle and seems to match up with the vehicle's weight distribution. The RL, which is the most nose-heavy, get the most power to the front wheels. So, each wheel gets as much power as it needs to move the weight it bears.
In corners, upwards of 70% of the power is routed to the rear, and may be sent to the outside rear wheel. That wheel is also overdriven by either 1.7 or 5%, depending on the vehicle. This is accomplished without braking. The front wheels retain 30% to pull the vehicle out at the end of the corner. (The last is similar to the way Nissan's ATTESA works.)
Of the 3 vehicles currently using SH-AWD, only the MDX has programming which automatically routes power to the rear for hill-climbing. It also has algorithm's for towing.
But it's kinda hard to divorce the AWD system from the car. For example, while SH-AWD is a better system than your basic torsen Quattro, I might take an A6 over an RL because the RL's chassis isn't up to par.
#57 of 96 Where is all these AWD cars in the real race?
Mar 25, 2007 (9:06 pm)
It looks to me like the real winners are Mitsubishi and Volkswagen. They won together 7 or the top 10 places in the grueling Dakar race. No Acura's or Subaru's in the mix. The only other vehicles in the top 10 best off road vehicles was Ford, BMW X3 and a Hummer 3. My only reason for wanting power to all 4 wheels is when I get in a sandy wash and want to get home by dinner. I don't think all the fancy electronic AWD vehicles are good for real off road driving. KISS is a better way to go.
#58 of 96 Re: Where is all these AWD cars in the real race? [gagrice]
Mar 26, 2007 (10:59 am)
No doubt. For off-highway driving, 4WD is better than AWD. But the question posed in the title is "Which car company has the best AWD system".
FWIW, a Honda Ridgeline passed many Fords, Hummers, and other 7S class competitors in the 2005 Baja 1000.
#59 of 96 Re: Real World... [stillwaters]
Mar 26, 2007 (10:50 pm)
Tires man, it's all about the tires...
So my idiot brother buys himself a new Subaru wagon (and thinking he has a REAL 4WD) drives it out to the beach and promptly buries his "grocery getter" in the sand...
So he calls me on his cel phone and after I laugh for several minutes (he hates that), I drove out to the beach in my Land Rover LR3, wrapped a tow strap around his chassis (had to dig down almost two feet to get there), and pulled him out pronto...
#60 of 96 Re: Real World... [sellaturcica]
Mar 26, 2007 (10:53 pm)
The answer to this question is Citroen, World Rally dominating champion for years now. Subaru had their day in the sun a few years ago, but downhill since then.
Jun 09, 2007 (9:51 am)
My take on this subject is that there isn't a whole lot of real world difference between the various systems for
everyday on-road or light off-road driving. Put another way, the differences are rather marginal, while the tradeoffs between AWD/4WD and 2WD are more significant. Every AWD/4WD system requires negative tradeoffs in terms of initial cost, fuel economy, handling (except at or near the limits), and complexity. It seems to me that for the vast majority of driving situations, in most of the country, FWD, with winter tires, when required, is a better compromise than AWD/4WD. For those willing to trade traction in slippery comditions for better weight ditribution, RWD, and winter tires for the months when it's helpful, may be the best compromise. In a minority of cases, AWD/4WD offers the best solution. In extreme cases, it's the only solution.
It seems to me that AWD systems that employ braking are wasteful, in terms of fuel and brake wear. I'm just not
sure how significant these losses are.
In my opinion, clever marketing has oversold the real world benefits of AWD/4WD, and conveniently neglected to mention the tradeoffs, for most driving requirements. It's what politicians tend to do when they try to sell a program.