J.M.G.

Yesterday, a few of my buddies took their Euro-Specs 2010 E550s to the Autobahn. The following video shows two E550s:
1. Stock with the 159mph-limiter
2. Stock with the limiter removed


The first E550 goes down the Autobahn with 159mph while the second overtakes him at 187mph (GPS measured!)!

alanme123

How was the ride? Any shake/loud noise?

J.M.G.

Thank you for your question. As the car is basically the same as the E63, which can be ordered from factory with a 186mph limiter over here, it is really rock solid. No problems at all. However, the airmatic could be a bit harder at those speeds.

BenzV12

That's totally impressive

Ferris_E550

Too bad we don't have Autobahn in Canada to set the E550 free

KEY08

Good to know I can get the beast up to that speed if I move to Germany.

thefisch

159 mph @ 3750 rpm - can't wait to book my flight for me and Clark!

Dema

Drop me a note when reach 200mph

sharpxia

2012 and newer E550 with increased HP, it should be able to reach 200MPH.

J.M.G.

I tend to disagree on that. Speed³ is proportional to power.


So if the 2010 E550 (382 hp) can reach 187mph, the 2012 E550 (402 hp) might reach up to 190mph.



(Speed [2012] / Speed [2010])^3 = Power [2012] / Power [2010]
Speed [2012] = (Power [2012] / Power [2010])^(1/3) * Speed [2010]
Speed [2012] = 190mph

In order to get up to 200mph, the E550 would have needed at least 467hp under those conditions.
(200mph / Speed [2010])^3 = Power [200mph] / Power [2010]
Power [200mph] = (200mph / Speed [2010])^3 * Power [2010]
Power [200mph] = 467hp

Tjdehya

You math is flawed... You forgot friction, mass, drag, and some more stuff.
I bet many engineers wish that making cars go fast was as simple as "more power!" Lol

J.M.G.

Thank you for your comment! Actually I did not forget drag, friction and inertia. Let us follow Newton and take a closer look into the forces that affect a car during straight forward driving:

Sum of all forces = 0 = driving force – aerodynamic drag – rolling drag – acceleration force – force due downhill/uphill grade – moment of inertia

Driving force = aero drag + rolling drag + accel. force + downhill + interia

OK, during a flat out the acceleration is zero (as the car reached its maximum speed). I also assume, that we are talking about a street without slope (force due downhill grade = zero)

Driving force = aero drag + rolling drag + inertia

Moment of inertia describes the inertia of all rotating stuff, like wheels, brake rotors and so on. It does not depend on speed and is only dependent on the cars properties. Therefore it is constant, as long as we are talking about the same car!

Driving force proportional aero drag + rolling drag

With

Aerodynamic drag = air density / 2 *coefficient of drag * frontal area * speed of the air^2
Rolling drag = coefficient of friction * gravity acceleration * mass

For a given car / street / weather, coefficient of drag, frontal area, air density, coefficient of friction, gravity acceleration and mass are constant! So we have got:

Driving force proportional aero const * speed ^2 + rolling const

Driving force proportional force const. speed^2

Now let us replace force with power. Power = Force * Speed!

Driving Power proportional speed^3

Here we go! Power proportional speed^3

If you wish, we can do a reality check. Let’s retrieve some technical data from Mercedes.de:
E200 Diesel : 136 PS / 131mph
E220 Diesel: 170 PS / 142mph
E250 Diesel: 204 PS / 151mph

Now I use the equation from above:

Power [E220] / Power [E200] =( speed [E220] / speed [E200])^3
Speed [E220] = (Power[E220] / Power[E200])^(1/3) * speed [E200] = (170/136)^(1/3) * 131mph
Speed[E220] = 141mph (remember – Mercedes said 142mph!)

Let’s do it for the E250 and E220 Diesel again:
Speed[E250] = (Power[E250] / Power[E220])^(1/3) * Speed[E220]
Speed[E250] = 150mph (Mercedes claims 151mph)

Close enough for a rule of thumb, isn’t it?

drsaab

I rented a E220 diesel there and it maxed out at 154 mph by engine, not limiter.

Awesome experience for us "70mph" limited folks.

sharpxia

Renntech upgraded E550 with 2012 and newer gets 530HP, so HP on calculation is enough to reach 200mph.

thefisch

J.M.G.

I am still waiting to see a dyno graph (crank!!!!) of an M278 @ 530 hp! I do not buy all those "estimates" from US-tuners, as they pretty much guess the drivetrain losses!


I saw a graph of an CLS 550 (Turbo), that pulled 376 RWHP (stock). The engine itself pulled 409 hp at the crank (and 455 ft lbs at the crank). As you can see: Less than 10% drivetrain losses with the new 7g-TronicPlus. So I can absolutely not understand, why some people claim, the M278 would develop more power than it is rated!

sharpxia

I have read that the actual Dyno on M278 is at least 450HP.

J.M.G.

I know many people claim that. However - none of them have got a proof. I have seen three different M 278 DE 46 AL red., as used in the E 550 / CLS 550 / ML 550, and they were all three spot on - 402hp +/- 2hp.

Arrie

You are absolutely correct with this. I would just leave the inertia out of it as it only matters if the cart is under acceleration (or deceleration). At the max speed of the car only the rolling resistance and wind resistance matter.


For any driving enthusiast here, do yourself a favor and make a trip to Germany and rent one of these cars (or another fast car) and go enjoy the roads. But it is best to do it at night as in general the roads are too full of cars at day time.


There are some A-bahns that are quite empty even in daytime though. I remember one going to old East Germany. My German friend calls it "race track" or something. Beautiful almost like new condition road and very few cars on it. Don't remember the number of it now.


One I do remember and drove it about 6 weeks ago is A9 going north of Munich to Nuremberg. At evening time this road is almost all the way no limit.


Another one I remember is A-96 from Munich to Memmingen. I have not been on this road for some years now but when I was it was very open almost all the way no limit and very few cars even at daytime. And Memminger is a very good beer too.


A nice trip to Germany is to fly to Munich and taste some real good beer (best in the world no matter what the Belgian guys say) and see around. It is close to Austria (Saltsburg), Czech (Prague) and Italy is not that far either (Garda Lake). The Alps all over if you drive south to Austria or Italy and, of course, if you would drive to Switzerland (very doable).


For car driver icing on the cake is to go drive when the roads are open.


I was lucky to rent a fast car some years ago. This was before I had my MB. It was an Audi A6 Avant Sports Line with a 3.0 TDI engine on it. This thing was fast and I did break the 1/4 thousand km/h mark with it and it did not feel uncomfortable at all. With this car I drove from Hattingen (close to Dusseldorf) to Raubling (south of Munich) 700 km in 4.5 hours in daytime traffic. It is only 155 km/h (97 mph) average speed but at daytime it is quite good as at some points you are dead stop for road work etc.


Really folks, go enjoy it. They are talking about putting speed limits on all Autobahns in Germany so this enjoyment may be going away...

v12driven

Johannes, the slower car looks like the rear trunk badges read "E200 CDI"?

tschüss from USA!

J.M.G.

That is nearly spot on. It has "E 200 CGI" on its trunk. My E550 has "E250 CGI"...we love the stealth look of our cars



ps: The manufacturer claim regarding the maximum speed can be easily exceeded, as long as it is not electronically limited. All you need is a decent downslope or tailwind... I just drove an E 220 Diesel Station wagon (170hp), and this car reached 143mph - with a manufacturer claim of 135mph:

AudiA4Turbo22

I've taken my E550 prior to being tuned up to 130MPH several times, it cuts the throttle at 130MPH, my ML550 on the other hand hit 140MPH and still wanted to climb(that was scary).

xxGenericSNxx

Haha awesome!

J.M.G.

Yeah, that 130mph limiter in US-specs cars drives many of us crazy, when importing Mercedes from the US.



It is a lot of fun, when playing with Porsche, AMG (C63 / A45) and so on. A real sleeper.

Dema

Nice discussion, so more likely E63 is capable to pass 200mph bar