How Can This Be?
 

I was reading through the July 12 M/T mag and it had a road test review on the 2013 BMW M5. Their performance numbers showed this 550hp/500 ft lb 4384lb curb weight car running the 1/4 mile in 11.9 @ 120.3 mph. How can a heavier car with 56 ft lbs less torque obtain these numbers? The numbers, to me, do not seem out of line. I just wonder why we have not seen any numbers like this with the ZL1. Seems like the ZL1 should be at worst equal.

The twin turbo V8 is probably putting down more power than you think. Combine that with an 8-speed DCT and you have your sub 12 sec quarter mile. Only cost $90k.

GM also said that the ZL1 had run at 11.9 , so....

it has to do with the "power and torque under the curve". Peak torque with these twin turbo BMWs and MBs is barely above idle and with the ZL1 it is at 4200rpm...huge real world difference. That equates to a few tenths in the 1/4 mile.

its all has to do with how the engine was built. The dyno sheet between the BMW V8 and the Chevy V8 must look different although they achieve similar horsepower. For example the torque curve must be different and possibly better in the BMW.

The other MAJOR factor is the transmission.

Weird also...MT pulled a 12.1 with the Zl1 and nobody is pulling that at the track

Anyone know if MT used corrected numbers?

There's a LOT of variables, which is something that people can't understand. The Chevy 11.9 and Motor Trend's 12.1 were probably under ideal conditions with a PROFESSIONAL driver behind the wheel.

:thumbsup:

MT showed the 12.1 on the best drivers car drag race

I think most magazines use a correction formula for their exceleration numbers.

I posted the motor trend vid of the new m5 in the general section awhile back. That car is a beast and a big luxury pig. I get what ur saying OP, and I still believe the zl1 is leaving something on the table. I think any of the V series cars could take the Z, and that should not be either?

High performance BMWs are always heavy and fast. Check out the transmission gear ratios compared to our Tremec 6060 ratios. That is an important part of the story. The BMW "M" cars usually have very aggressive gear ratios for the first 2-3 gears to get their cars out of the hole and on down the track. Plus they often have a high redline so that they can pull that better gear ratio a little longer between shifts. Its a deadly combo - better gearing for acceleration and higher redlines to leverage it.

Oh - And it really ticks me off too!

What’s Hot:
Responsive, high-revving turbocharged engine
Excellent handling
Able to customize drivetrain/chassis setup to your style
What’s Not:
Tame exterior styling
Slightly numb on-center steering
BMW M5 »
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2013 BMW M5
Specifications
List price est $100,000
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Curb weight est 4288 lb
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Wheelbase 116.7 in.
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Length 193.3 in.
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Width 74.4 in.
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Height 57.3 in.
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Coefficient of drag 0.33
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Engine & Drivetrain
Type alum. block & heads, variable valve timing & lift, dohc 4-valve/cyl twin-turbo longitudinal V-8
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Displacement 4395 cc
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Bore x stroke 88.3 x 89.0 mm
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Compression ratio 10.0:1
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Horsepower (SAE) 560 bhp @ 6000–7000 rpm
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Weight-to-power ratio 7.66 lb/hp
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Torque 502 lb-ft @ 1500–5750 rpm
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Redline/limiter 7200/7200 rpm
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Fueling direct injection
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Recommended fuel premium
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Transmission 7-speed dual-clutch automated manual
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Chassis & Body
Layout front engine/rear drive
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Body/frame unit steel w/aluminum hood, fenders & doors
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Brakes, f/r 15.7-in. vented, floating & drilled rotors, 6-piston fixed calipers/15.6-in. vented, floating & drilled rotors, 1-piston sliding calipers
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Wheels cast alloy; 19 x 9 f, 19 x 10 r
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Tires Michelin Pilot Super Sport; 265/40ZR-19 102Y f, 295/35ZR-19 104Y r
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Steering rack & pinion, hydraulic assist
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Steering ratio 18.0:1
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Suspension, f/r upper & lower control arms, coil springs, elect. adj tube shocks, anti-roll bar/multilink, coil springs, elect. adj tube shocks, anti-roll bar

Just take a look at its torque numbers and how long it last. When Chevy and ford go turbo insteadp of super chargers prepare for things to get silly fast in a hurry. Also having that extra gear helps move all that weight while still maintaining decent mpg's.

LoL..... a sub-12 sec Camaro ZL1 claim by GM........Kinda sounds like a marketing strategy......would you buy a $60,000 Camaro if they told you it runs a 12.65 @ 113mph ??? or would you be seriously more inclined after you saw the GM video about them running a 11.91(or somewhere in that region)......