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Acura, Infiniti, Volvo
#74 of 96 Re: X-Drive [quattroporte12]
Mar 24, 2008 (10:00 am)
I think you misread something. SH-AWD does not rely on wheelspin.
Well, I guess the wheels must be "spinning" to some degree. No AWD is going to work if the wheels are stopped.
Here's a snippet from Acura's description of the RL:
The logic and control of SH-AWD™ is integrated with the RL engine's Electronic Control Unit (ECU) and Vehicle Stability Assist™ (VSA®) ECU. The Engine ECU provides engine rpm, throttle position, intake manifold pressure, and transmission gear ratio data. The VSA® ECU provides data on lateral g, yaw rate, wheel rotation speed and steering angle. The SH-AWD™ ECU monitors the status of the acceleration device and the distribution of right and left Direct Electromagnetic Clutch torque. Traction is calculated based on the information from the engine ECU. During a hard acceleration situation, lateral g and steering angle are used to calculate the torque split between the right and left rear wheels. At the same time, this data is used to control the total amount (ranging between 0.6- and 5.7-percent) of rear wheel acceleration.
Mar 24, 2008 (8:05 pm)
Yeah youre right sorry i forgot what it exactly was that i read i saw that article like 2 months ago. but...i just looked it up again, its a first drive of the X6 with motortrend, and they explain that the new x-drive system is always functioning, even in cornering situations when no throttle is given to the car. With acuras superhandling awd, the system is only active when throttle imput is given to the car, and therefore if the car starts to understeer and you need to lay off the gas mid corner, the awd isnt going to be functioning and the understeer can turn into oversteer. This is where the bmws new x-drive pulls ahead, because it can transfer touque between each wheel witin the axel just like the superhandling awd, plus it has the usual bmw saftey conviences (i think 6 total, i dont remember all of them) like dsc etc...
#76 of 96 Re: X-Drive [quattroporte12]
Mar 25, 2008 (10:23 am)
Yeah, that part is true. If you lift all the way off the throttle, SH-AWD stops modulating the torque split.
However, IIRC, the new Xdrive doesn't overdrive the outside wheel (change it's speed) it just supplies more torque. My memory is also fuzzy on the details.
#77 of 96 Matrix/Vibe vs Subaru Imprezza
Mar 28, 2009 (8:43 pm)
My son wanted an AWD car while in college in upstate New York. 147 inches so far this winter in Syracuse. Based on budget and the AWD requirement, we agreed on the Matrix/Vibe or the Subaru Imprezza Outback Sport.
He liked the styling of the Matrix while I liked what I had read about the ride/handling/traction of the Subaru. We were about to get the Matrix when the Subaru sales lady suggested that my son drive them back to back and push them hard. I suggested that we also find a slippery area to test the AWD systems. Besides the better on center tracking and cornering testing of the Subaru, we found a muddy road behind the dealership. The Subaru went up the hill. The Matrix couldn't.
#78 of 96 Re: Matrix/Vibe vs Subaru Imprezza [lch77]
by steve_ HOST
Mar 28, 2009 (9:53 pm)
It's the tires.
I'm running all-seasons on my Outback and if I wasn't paying attention, I could lose it on the snowy road going up to my local ski hill.
#79 of 96 Re: Matrix/Vibe vs Subaru Imprezza [steve_]
Mar 29, 2009 (12:23 am)
But don't both Imprezas and Matrixes come with fairly crappy OEM all-season tires? I'm pretty sure they do.
My $0.02 would be that the Impreza has stability and traction control and the Matrix probably doesn't - I don't think it's standard on Matrix and is in fact a fairly hard-to-find option.
Which for the money definitely swings the advantage in favor of the Subaru, IMO.
#80 of 96 Re: Matrix/Vibe vs Subaru Imprezza [nippononly]
by kyfdx HOST
Mar 29, 2009 (7:12 am)
fairly crappy OEM all-season tires
That doesn't even begin to describe the (lack of) snow capabilities of the Bridgestones on my Impreza...
I understand why they put cheap tires that wear out fast on new cars... but, putting these tires on a full-time AWD car is criminal..
Given similar tires, I'd have to agree that the Subaru has it all over the Matrix in the AWD department, though.
#81 of 96 Re: Matrix/Vibe vs Subaru Imprezza [kyfdx]
Mar 29, 2009 (8:26 am)
A co-worker of mine's other half bought a new STi last year. Endless complaints about the tires.
#82 of 96 Re: Matrix/Vibe vs Subaru Imprezza [fintail]
Mar 29, 2009 (1:02 pm)
I saw a comment somewhere the other day about how the Potenza RE92 was quite possibly the worst tire in existence, and I know I would have to agree as that is what was on my last new Subaru when it came from the factory.
I hope they don't still use those, but I fear they just might.....not on STIs though, thank goodness!
#83 of 96 Re: Matrix/Vibe vs Subaru Imprezza [fintail]
Mar 29, 2009 (2:23 pm)
My test was unscientific and I recognized that to be fair both cars should have the same tires, BUT if I bought either car, the tires tested would be the ones I got.
The Impreza did have the above mentioned RE92's (described as awful) but did make it up the hill anyway. Just for the fun of it, I tried the hill today with my 2002 A4 Quattro with Michelin Exalto Sport A/S tires. It rained last night so it was even muddier than it was yesterday To my surprise, the A4 did NOT make it up the hill either. It does have ASC which I left turned on. It does not have a differential lock like my 1990 Audi 200 Quattro did.
BTW, both the Subaru WRX and WRX STI come standard with high performance SUMMER tires. I think you'll see that everyone agrees that if you these tires in snow country, you MUST switch to either Snow or All Season tires in winter.