clktoc63

Per the Road & Track Review of the C63 Black: (Thanks for posting)

Compared to the 510hp of the Black Series..."A standard C63, for the record, puts out 451 bhp at 6500 rpm and 443 lb.-ft, of torque at 5000. While that’s quite a gain in power for the Black Series V-8, which has the same compression ratio, heads and camshafts, the folks at AMG say reduced gas pressure within the crankcase plays a significant role."

Any motorheads out there that can elaborate here? Seems like something JCart, Dads or Andy would be very interested in.

Would be great if it means just adding a PCV valve or something (?)

SonnyakaPig

I noticed that too. The way I look at it, is the extra power (compared to a regular C63) not attributable to the TB's opening up more and a slightly revised exhaust system?

Seems kind of awekward that on this version of the M156, AMG found some extra ponies by reducing gas pressure in the crankcase. To me, it's all marketing. I believe it's just a regular old M156 like you would find in the E, CLS, etc.

hhughes1

MB just won't admit that the M156 makes 510 in it's default setting and the C63 is an example of intentionally holding back thru the ECU. Now that the other models have moved on to TT, MB is suddenly concerned about offending the C class crowd when they weren't before.

SonnyakaPig

Well said.

clktoc63

Just did some "googling" and found the following info on a VW forum. The argument from the poster seems interesting considering our unique oil smoke nuance with our 63's; which I presume is due to loose clearances for our piston rings (?).

"Pulling a vacuum on a sealed crankcase is good for a tried and true 5% horsepower gain (on a VW TDI). The horsepower gain is due to the crankcase vacuum pulling oil off of the rings, allowing them to seal better. Drag racers run weaker (looser) piston rings since they too seal better than tighter rings.

The lower the crankcase pressure, the less the engine will have to pump air out of the engine and there will be less pressure on the bottoms of the pistons reducing the amount of pumping the engine has to do. Also, a vacuum on the crankcase will keep the seals more oil tight since the vacuum pulls the oil into the engine instead of pumping it out."

Maybe the engineers at AMG were being honest with R&T and figured this out???

hhughes1

You do realize that this same motor has been making 500+ HP in every other model other than the C63 for six years. Why do you think ECU tunes are so effective for this car? It has nothing to do with crankcase pressure, MB did not just find a way to get the M156 to make more power, they simply chose not to withhold it.

DuaneC63

+1. The motor is detuned in the standard C63 to maintain a marketing differencial for E and S class cars. I've driven an E63 and my car back to back and you can actually feel the ECU holding the C63 engine back.

clktoc63

Fully agree, I have a tune myself! Given our car's oil smoke, I also see logic in the explanation above and that message being confirmed by AMG and then published by Road & Track.

We certainly can all choose to ignore it and believe that all three unrelated parties have plotted something and attribute all gains to the tune. I'm not a big conspiracy theory guy and thought as fellow enthusiasts we would want to look into the information being presented.

Dueclaws

I believe MBZ has done the same thing (withhold) with the new biturbo M278 engine.
Rated 429 bhp in the Cl and 402bhp in the CLS550 and E550. A simple tune puts these engines over 440 bhp/508 tq.
http://www.youtube.com/user/OEtuning...12/TUQxtSnGD_o
Brabus takes it even higher (500 bhp/531 tq) by adding an additional intercooler.

On subject: I've read about the crankshaft pressure and some manufacturers (Mercedes) are now "porting" (drill Pulsation holes in the main bearing webs) the inside of the crankcase to relieve pressure.

Dueclaws

Look at this site: http://www.marcusfitzhugh.com/CLK/M278.html
Go down to the description of the new 5.5 AMG engine where the Pulsation holes are discussed.

MRAMG1

Keep in mind that, your info was on a Diesel, which runs MUCH higher compression. Hence, more potential for crankcase pressure.

Drag racers use a crankcase evac system connected to their headers. It is good for about 10-15 hp. Moroso sells a universal kit for it.

It will NOT work on modern cars, as it replaces the PVC system, and requires it to be the ONLY system on the engine as it creates a slight vacuum in the valve covers to draw out ANY blow by.

I would REALLY doubt, that this is were the AMG engineers picked up 50 hp

Chocofishez

This is what people have been saying about the P31... that it was just the same motor in the E or SL but given a lower number on paper so as not to offed those that bought the bigger cars. None of the tuners can add anything to a P31 tune and it pulls as hard as a tuned standard C63.

So if the P31 is just a regular M156 without a 'de-tune' (not sure what the "forged internals" adds) what is in the motor in the BS that makes it a worthy upgrade over a PP car?

Would really love to see a breakdown of what goes into the motors of the AMGs to go from C63->C63pp ->E63 / S63-SL 63 -> C63 BS -> SLS

SonnyakaPig

C63 = neutered TB openining
C63 P31 = regular M156 with forged internals from SLS
E63 = regular M156 + larger diamater exhaust (more power)
C63 BS = regular M156 + a unique catback (probably a resonator delete)
SLS (M159) = M156 + forged internals + revised cams + revised intake manifold + better heads + different exhaust

Chocofishez

Wow.. Thanks!

SonnyakaPig

No problem.

c32AMG-DTM

Fixed (unless there's more?).

SonnyakaPig

Thank you.

justthebest

Um, not sure about the exact conversion, but I received a '12 CLS with 550 hp, which seems to be the top of that particular motor's factory spec.

hhughes1

He is referring to the CLS 550

Dueclaws

Correct.

I clarified my previous post to show CLS550.
(CLS63 is not 402 hp)

Thanks!

clktoc63

Back to the original point made by AMG and Road and Track, if there is an easy way to measure it, it would be interesting to see if there's a difference in crankcase pressure between the BS and the standard 63.

rage2

Here's a new one from the inside line article.

http://www.insideline.com/mercedes-b...ck-series.html

Am I reading it right that there's MORE crankcase pressure to create more hp?

MRAMG1

More importantly than ANY of this dribble, did you catch this statement:

"From there, the path to 510 horses and 457 pound-feet of torque involves a stop at the SLS AMG parts bin, where forged pistons, forged rods and a lighter forged crank amount to a 9-pound loss of reciprocating engine mass. "

9 Pounds loss of reciprocating mass, and they really did not gain much over a base C63 with a tune.

So much for the lighter balancer of a few ounces

I know, she will rev alot faster with that balancer