Don't understand how come the C55 with a 5,5 liter engine 'only' produces 370 HP and the new Audi rs4 gets 420 HP out of a 'small' 4,2 liter engine.

Time to make the swap ???

 

rumors has it that there is a tiny monster called the C63 coming up. Be patient my small grasshopper. I just got a C32 and until i don't see the new C i am not making no type of swapping.

 

Take a look a the torque figures on both engines. You might begin to appreciate the amg engine a little more.

 

The Honda S2000 makes 240hp from 2 liters, that would be over 500hp if it were a 4.2 liter. It's all about how a manufacturer wants to design/tune the engine. The Audi and Honda motor have very little torque and are not as driveable on the street.

 

I believe the C63 was killed no?

 

really, I hope not, How will MB keep up with the new BMW M, RS4, and not to mention the CTS V? All of these cars will be well above 420HP. My day is ruined if they decided to kill it.

 

Just wait till Cadillac makes the CTS-V+ with either the 500 horse Z06 engine or the 600 horse Blue Devil engine (depending if the latter makes it to production).

 

Agreed with Zepplin.
Another example is Mazada Rx7 Rotary engine, it is ~1.3 litre and it delivers 250hp! And, that thing probably drinks as much fuel as the 5.5 litre.

In marketing view point, M3, S4 and C55 are very different designed cars aim for different market consumers. A BMW lover will not go and buy a Benz just because the C55 is 10-15% more hp than the M3. It is much easier for MB to make sure a Benz lover will find a Benz as fun as power and as fun as the M3.

In engine design view point, I dont know engines design well to defend for MB. However, it is still how well an engine power is translated into performance, handling, safety and fuel efficiency that matter most.
M3 is a winner on power and handling and great powerful 3 litre engine. And then, it is still not a V8

 

first, a little edjamacation:

HP is the application of torque to the crank at a rate of revolution (i.e. "work")

HP = Torque * RPM / 5252
thus also
Torque = HP * 5252 / RPM

..no two ways about it ... that's how you calculate HP from torque or torque from HP. Notice how as RPM goes up, HP goes up in like kind, because it's being multiplied to the torque value.

Our 5.4L engines "shoot their load early", with torque peaking in the 3K range, and significant torque rolloff above 5500 - 6000 rpm. However, absolute torque produced by them is

That Audi engine has a +8000rpm redline. Though that engine doesn't produce much more torque then my old 4.3L AMG engine that came stock in my car before (the new 4.2L Audi engine is about 325 ft-lbs of torque), that torque stays flat well well up into the RPM stratosphere ... resulting in the high HP figure.

The fact is, the higher you can raise your redline -- while ensuring that your torque does not trailing off too rapidly, which is a function of how well you can enable the engine breathing at high rpms, minimizing rotational momentum, keep your valves operating efficiently, many many more factors -- the higher your HP rating of your engine will be.

However, With that Audi engine:

A) final rear (and front as it's AWD) differential gearing of the car =must= be very short (high numeric ratio) compared to what we run in MBs, to provide enough torque multiplication through gearing, to compensate for the "meek" torque the engine produces.

B) The driver WILL HAVE TO take the engine up to the 8K redline to get the most out of it, and compete with our Hi torque "relatively low RPM" AMG engines. If the driver of the RS4 short shift it in the 6K range, given its weight and drivetrain resistance of AWD, perfomance of the car will be on-par with say, a new C350 or SLK350.

 

you may also want to consider how come the 2006 BMW M5/6 only get 500hp and 383 lb/ft tq from a 5.0 LITER V10?? i mean thats 100hp/liter, but still the AMG 63's are getting about 510hp and 465 lb/ft tq from a 6.2 LITER V8. Would the 1.2liter make a difference EVEN IF ITS TWO CYLINDERS SHORT, yes and no, like stated by C55M80 it depends what the manufacturers want to focus on.

 

Yeah, but that Honda S2000 is one hell of a car...trust me I drive one daily....wifey's car. High revving concept with a lightweight car======
SUPER EXCITING RIDE< BUT YOU ARE RIGHT ABOUT TORQUE< IT REALLY KICKS IN AT AROUND 6000k rpm.

 

have you compared S2000 with SLK55 . I am curious as SLK should be felt much 'lighter' with that C55 torque goes into it :p

 

Absolutely perfect expression!

 

LoL I gotta credit and thank Carl (coolcarlski43) for that one... :p

 

BTW, your explanations were spot on as well!