Powertrain Enhancements for the new TT V8 and Seven Speed Trans
01-18-2011, 01:07 PM
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Powertrain Enhancements for the new TT V8 and Seven Speed Trans
Here's some info for the '11 CL550 which has the new TT 4.6L engine and refinements to the seven speed trans which will carry over to the rest of the cars with the new TT 4.6L engines...note the 600 will still be using the 5 speed to handle its massive torque.
The new engine in the 2011 Mercedes-Benz CL550 is mated to a seven-speed automatic transmission which has undergone significant revision, while V12 models retain the proven five-speed automatic transmission due to their extremely high torque at low engine speeds. The DIRECT-SELECT lever on the steering column enables the driver to select “P”, “N”, “R” and “D” by nudging the selector. The operating commands are transferred electronically by wire.
A new hydraulic circuit and optimized torque converter characteristics also help to improve efficiency and performance. A further consumption-cutting measure is a new lower-viscosity automatic transmission fluid (ATF), which has a longer life yet the same cooling performance. As a result, the 2011 Mercedes-Benz CL550 4MATIC only needs a transmission fluid change every 78,000 miles.
The optimized electrohydraulic control unit of the transmission and new reducedfriction materials in various parts of the transmission in combination with optimized software provide greater shifting comfort.
Some info on the new TT engine in the CL application; it appears MB is using the latest version of DFI which should make it less problematic than the first DFI engines used by Audi, Porsche and BMW...
With its 4,663 cubic centimeters of displacement the new V8 biturbo engine in the 2011 Mercedes-Benz CL550 4MATIC features BlueDIRECT technology and delivers impressive power. The eight-cylinder engine produces 429 hp so that despite 0.8 liters less displacement, it is still around 12 percent more powerful than its predecessor. At the same time, torque was raised to 516 lb-ft – an increase of 32 percent. The Mercedez-Benz CL550 4MATIC requires a mere 4.8 seconds to accelerate from a standstill to 60 mph. In summary, the 2011 CL550 4MATIC is significantly more agile, torquey and fuel efficient than its predecessor.
The BlueDIRECT technology of the V8 biturbo includes an impressive combination of new developments such as third generation spray-guided direct gasoline injection with piezo injectors and multi-spark ignition with up to four ignition sparks within a millisecond.
Some excerpts from the Car and Driver short test; the new 550 is faster than the 63 in 0-60 and equally fast in the QM!
Not that the CL550 is slow. No, no. It scoots from 0 to 60 mph in 4.2 seconds, bettering the pace of the CL63 we tested in October 2007 by 0.1 second, and covers a quarter-mile in an equal 12.8 seconds.
But frisky is not what comes to mind when hustling the CL along some twisty stretch of unknown back road. The car has plenty of grip, well-controlled body motions, and powerful brakes, but the combination of SUV mass and steering that’s a little numb makes it tricky to place this big coupe precisely on apex-clipping expeditions.
On the other hand, plenty of smooth power—instantly available, as linear as an aircraft carrier launch—is hard to resist, and the seven-speed automatic makes the most of it.
The new engine in the 2011 Mercedes-Benz CL550 is mated to a seven-speed automatic transmission which has undergone significant revision, while V12 models retain the proven five-speed automatic transmission due to their extremely high torque at low engine speeds. The DIRECT-SELECT lever on the steering column enables the driver to select “P”, “N”, “R” and “D” by nudging the selector. The operating commands are transferred electronically by wire.
A new hydraulic circuit and optimized torque converter characteristics also help to improve efficiency and performance. A further consumption-cutting measure is a new lower-viscosity automatic transmission fluid (ATF), which has a longer life yet the same cooling performance. As a result, the 2011 Mercedes-Benz CL550 4MATIC only needs a transmission fluid change every 78,000 miles.
The optimized electrohydraulic control unit of the transmission and new reducedfriction materials in various parts of the transmission in combination with optimized software provide greater shifting comfort.
Some info on the new TT engine in the CL application; it appears MB is using the latest version of DFI which should make it less problematic than the first DFI engines used by Audi, Porsche and BMW...
With its 4,663 cubic centimeters of displacement the new V8 biturbo engine in the 2011 Mercedes-Benz CL550 4MATIC features BlueDIRECT technology and delivers impressive power. The eight-cylinder engine produces 429 hp so that despite 0.8 liters less displacement, it is still around 12 percent more powerful than its predecessor. At the same time, torque was raised to 516 lb-ft – an increase of 32 percent. The Mercedez-Benz CL550 4MATIC requires a mere 4.8 seconds to accelerate from a standstill to 60 mph. In summary, the 2011 CL550 4MATIC is significantly more agile, torquey and fuel efficient than its predecessor.
The BlueDIRECT technology of the V8 biturbo includes an impressive combination of new developments such as third generation spray-guided direct gasoline injection with piezo injectors and multi-spark ignition with up to four ignition sparks within a millisecond.
Some excerpts from the Car and Driver short test; the new 550 is faster than the 63 in 0-60 and equally fast in the QM!
Not that the CL550 is slow. No, no. It scoots from 0 to 60 mph in 4.2 seconds, bettering the pace of the CL63 we tested in October 2007 by 0.1 second, and covers a quarter-mile in an equal 12.8 seconds.
But frisky is not what comes to mind when hustling the CL along some twisty stretch of unknown back road. The car has plenty of grip, well-controlled body motions, and powerful brakes, but the combination of SUV mass and steering that’s a little numb makes it tricky to place this big coupe precisely on apex-clipping expeditions.
On the other hand, plenty of smooth power—instantly available, as linear as an aircraft carrier launch—is hard to resist, and the seven-speed automatic makes the most of it.
Last edited by RJC; 01-18-2011 at 03:08 PM.
01-20-2011, 04:18 PM
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I drove a new '11 CL550 with the new 4.6 DFI TT engine and upgraded trans
Pros:
Trans is truly further refined with ultra smooth shifting under all situations
Top end power is excellent contrary to popular belief
There was no start/stop feature that I could find but I did not go too far into the Eco mode settings
There is still a nice rumble from the exhaust
Fuel economy is up 2-3 but the car starts off in second gear even with Eco mode off; I don't recall if it changes in sport.
Cons:
There is turbo lag in light to moderate throttle applications, although full power or kickdown produces almost instantaneous power
The turbos constantly hiss like an 18 wheeler's even at moderate throttle. I found this very un-Mercedes like and very annoying; maybe a teenager would like it but not me
There is a vibration at idle that I do not recall in the 5.5 NA engine
Summary:
I think I prefer the NA engine for most applications, but I must admit when the turbos are spooled the car (all 5000+/-lbs of it) is a rocket. There's no doubt the '12 E550 should smoke the NA version. There is a neat little BlueEfficiency fender badge (see pic).
lease rates on the W212's are poor so for those that want to pay cash should probably wait for the 12's to protect resale value, but then again I wonder if some may prefer the normal daily driving experience of the NA cars and thus hold their value better than expected?
I personally am in a quandary; there is a perfect '11 with my name on it at the dealership or do I get the '12 knowing the resale value should be better equating to $5k or more. I was also promised a July delivery if I want a '12 so the wait won't be too long and I can order the car exactly the way I want, as the '11 I have a depo on does not have the side skirts. If I only knew for sure the dash material would be upgraded it would make my decision easier.
Pros:
Trans is truly further refined with ultra smooth shifting under all situations
Top end power is excellent contrary to popular belief
There was no start/stop feature that I could find but I did not go too far into the Eco mode settings
There is still a nice rumble from the exhaust
Fuel economy is up 2-3 but the car starts off in second gear even with Eco mode off; I don't recall if it changes in sport.
Cons:
There is turbo lag in light to moderate throttle applications, although full power or kickdown produces almost instantaneous power
The turbos constantly hiss like an 18 wheeler's even at moderate throttle. I found this very un-Mercedes like and very annoying; maybe a teenager would like it but not me
There is a vibration at idle that I do not recall in the 5.5 NA engine
Summary:
I think I prefer the NA engine for most applications, but I must admit when the turbos are spooled the car (all 5000+/-lbs of it) is a rocket. There's no doubt the '12 E550 should smoke the NA version. There is a neat little BlueEfficiency fender badge (see pic).
lease rates on the W212's are poor so for those that want to pay cash should probably wait for the 12's to protect resale value, but then again I wonder if some may prefer the normal daily driving experience of the NA cars and thus hold their value better than expected?
I personally am in a quandary; there is a perfect '11 with my name on it at the dealership or do I get the '12 knowing the resale value should be better equating to $5k or more. I was also promised a July delivery if I want a '12 so the wait won't be too long and I can order the car exactly the way I want, as the '11 I have a depo on does not have the side skirts. If I only knew for sure the dash material would be upgraded it would make my decision easier.
Last edited by RJC; 01-20-2011 at 04:24 PM.
