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01-09-2014, 03:56 PM | #1 |
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Why does the 428 accelerate so faster than the sDrive2.8?
Saw on Edmunds - http://www.edmunds.com/bmw/4-series/...oad-test1.html - an instrumented test of the 428 / 8-speed auto where they were getting 0-60 times of 5.4 seconds. Car & Driver's current issue has similar results.
Wondering why the X1 sDrive 2.8 doesn't match this performance as from what I can tell they have the same engine and the transmissions (identical ratios per the BMW website). The difference in weight is negligible (3470 lbs. for the 428 and 3527 for the X1 - again, per the BMW website). |
01-09-2014, 04:38 PM | #2 |
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The official BMW numbers are 5.7 vs 6.2, so they are actually close. The weight is still a factor. The moon roof is standard on 428 and optional on X1. Most X1 that magazines test have moonroof, thats another 80 to 100 lbs. Other than that it could be tire traction (e.g. summer vs. all season) or final drive ratio.
Note: They have the same gearing, so it is the weight and potentially different tires on 428. Last edited by MazdaFan; 01-09-2014 at 04:50 PM.. |
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01-09-2014, 05:49 PM | #3 |
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Possibly suspension difference? Technically the X1 being the SAV, does it have "softer" suspension? I'm just throwing it out there - I've noticed it DOES have some body roll in it during hard turns. I'm assuming more roll than that of the 3 or 4 series.
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01-09-2014, 06:12 PM | #4 |
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Aerodynamics might play into the #s as well (more so at higher speeds for sure). 428i is rated at .28 Cd and the X1 at .32 Cd. Not a huge difference, but once you add that to the all season tires, perhaps throttle mapping differences, transmission programming differences, air intake differences, etc....you might get yourself up to that .5 second difference.
Most places I've read though put the sDrive28i at 6 seconds flat to 60. So a bit better than BMW claims.
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Current Cars: 2019 X5 xDrive40i M-Sport, 2018 Camaro ZL1 Past BMWs: '16 528i, '00 M-Coupe, '14 X1 sDrive28i, '00 740iL, '02 325i, '99 M-Coupe, '00 323Ci, '79 323i, '83 320i |
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01-09-2014, 11:37 PM | #5 |
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I've read mags testing a loaded X128i xdrive and achieve 0-60 times of 6 flat. That's not a lot slower than the 428i. Also, what rear end gear does each use? The rear gear makes a ridiculous difference in acceleration.
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01-10-2014, 10:01 AM | #6 |
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aerodynamics plays the biggest effect, with height of the F32 vs. the height of the E84. the 428 probably has a different tune also, to help with the weight of the F32 vs. the E84
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01-10-2014, 10:05 AM | #7 |
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I could see aerodynamics and/or ride height making a difference in the 1/4 mile, but not 0-60. A barn should be only just a little slower than an SR-71 to 60 if they both have the same power to weight (and if the barn has wheels, of course).
I'd guess it all has to do with tires, has someone compared an M Sport X1 28i sDrive to a 428i with similar tires? |
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01-11-2014, 10:10 AM | #9 | |
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Quote:
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01-11-2014, 01:24 PM | #10 | |
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And why do people use those mediocre all season tyres? |
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