10-25-2016, 05:47 AM | #67 | |
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So while I do not question the RS6 having torque steer as you mention, I'm not certain it's caused by the diff being placed on one side, but suspect it's just as much highlighted because of uneven road surface (if the car changes the direction the front wheels pull, then that is caused by how the tires and surface are relative to each other). The BMW solution of having the diff Attached to the side of the engine and not to the side of the transmission as per Audi, means that the engine still is positioned just as far back as in a RWD BMW. So while X-drive adds weight to the front axle, the weight distribution isn't as bad as on an Audi... In this test of the S6 vs 550i X-drive AMuS weighed the cars and got the following weight distribution: http://www.auto-motor-und-sport.de/v...hnische-daten/ Audi S6 Q: 56,5 / 43,5 % 550i X-drive: 53,5 / 46,5 % A modern day 5-series With RWD is usually somewhere around 51-52 / 48-49 % The 335i goes from 50,8 to 52,1 % front bias according to this article: http://www.caranddriver.com/comparis...-bimmer-page-4 So while the X-drive obviously makes the car more nose heavy, it's not as dramatic as an Audi's weight distribution. |
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10-25-2016, 01:30 PM | #68 | |
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The RS6 definitely always pulls the same way when getting onto the throttle and comes back again when you lift off. I've done this on a wide variety of surfaces and ones that are cambered both ways. BMWUSA lists weights and weight distribution of almost all of the cars. I've picked the 5 below as well as the G12 7 as there are only LWB 7's in the US now. Note their site doesn't discuss the specs of the specific car weighed, so of course it isn't possible to be perfectly accurate on the differences. F10 528i 3814 49.4/50.6 528i x 4001 50.1/49.9 535i 3957 49.6/50.4 535i x 4156 51.7/48.3 550i 4277 51.5/48.5 550i x 4431 53.0/47.0 G30 530i 3746 51.5/48.5 530i x 3878 52.5/47.5 540i 3847 52.2/47.8 540i x 4019 53.8/46.2 G12 740il 4195 51.4/48.6 740il x 4361 52.4/47.6 750il 4502 53.4/46.6 750il x 4623 54.4/45.6 x drive adds from 121lbs to 166lbs in the G12 and 154lbs to 199lbs in the F10. In the G30 it adds 132lbs to 172lbs. It adds around 1 to 1.6% of weight at the front, ignoring the outliers of the 528i and 535i which add the most weight and are only 0.7% and 2.1% which are quite different to the other models. I suspect that as the G30 while losing 68-137lbs also adds on 2.1% to 2.6% forward weight that a G30 V8 will be very front heavy and that is why there is a need for 4WD in the V8 powered cars, both M550i and M5. I suspect the G30 M5 will be 54-55% front heavy in RWD and 55.5-56.5% front heavy in 4WD. And still 4250-4300lbs or 4350-4400lbs with 4WD. Of course you'll basically need 4WD to get any power down due to a lack of rear weight, but adding 4WD will make it even more front heavy. I've laid this out too in my other thread on here too. |
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10-25-2016, 03:03 PM | #69 | ||
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I don't think I've asked this specifically, but the RS6 you've been driving isn't by chance equipped with Air Suspension and Dunlop tires is it? |
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10-25-2016, 11:55 PM | #70 |
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Actually two different ones, both with air suspension. The first one was an early 2014 car with Pirelli P Zero originally, then Dunlop (but I can't remember what model exactly) I drove it with both tyres. The new one is a 2016 facelift and has Continentals on it.
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10-26-2016, 12:00 AM | #71 | |
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10-26-2016, 12:33 AM | #72 | |
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Coming slightly back on topic, should the extra length of the intermediate shaft still create a small amount of torque steer that is detectable? In my experience it was very noticeable, and there are plenty of people discussing it in powerful front wheel drive cars which now use that same overall concept of offset front diff and various alignment or suspension tricks to try and get around it. My overall point though is that I'd prefer the front wheels feeling to be the same at all times, ie to have no dilution in consistency from the power delivery. |
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11-06-2016, 05:57 AM | #74 | ||
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So torque steer also happens on cars with equal length drive shafts. Have there been many reviews on the RS6 that mentions torque steer BTW? |
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