gago1101

Please help. I am waiting to buy a 2012 C63 and will be doing an ECU update. Initially I thought I could get the base model and update the ECU. But now I am reading that the new 2012 C63 p31 package will have forged pistons, rods and lightweight crankshaft.

here is the quote: "Mercedes-AMG also offers the AMG Development Package, which gives the 2012 C63 AMG Coupe a total power output of 481 horsepower. This optional package uses forged pistons, connecting rods and lightweight crankshaft adopted from the Mercedes-AMG SLS gullwing model."

Is this true and if so one could expect higher gains on the new p31 package, I am assuming?

thanks

I am Jeff

If u're going to tune the car, there is no point to the P31 package other than the fact that you want it. Tuned non p31 = tune p31.

bli8

wouldn't a tuned P31>tuned non-P31 and has a more bullet proof engine?

C63newdude

Searching it for you.

gago1101

I did confirm on the AMG website that the p31 package has forged pistons and lightweight crankshaft, in addition to better brakes. I think that does it for me, even if both stock and p31 will have the same HP after the tune, p31 engine should outperform the stock engine in the long run.

Sheep

We had a trend about this a week ago on this exact topic. The bottom line is that a ECU only tuned non-P30 C63, and this includes the P30, dyno almost exactly as a stock C63 with P31. Of course if you add headers and/pipes/whatever than it will be different.

Sheep

khmergod

The current P31 has the exact same internals...

propain

That dyno compare was wacky. I think we need more results before we can say.

I would say if you plan on tuning the car then avoid the P31. If you plan on taking it on the twisties then the P31 might be better for you. Better brakes and maybe with the lighter weight internals will perform better in that scenario.

If you plan on doing 1/4 mile runs and light to light racing a P30 with a tune is all you need and you just saved yourself like 3K.

enochroot

When they refer to the "...lightweight crankshaft adopted from the Mercedes-AMG SLS gullwing model."

The SLS has: carbon-fiber driveshaft that spins at crankshaft speed and feeds into a rear-mounted AMG 7-speed double-clutch automatic transaxle.

Exactly which part of that ends up in the P31?

gago1101

No offense, but which part of what you mentioned is part of the actual engine, the drvishaft or the transmission?

gago1101

Thanks guys, I really appreciate all the input. I did some searching within mbworld. It seems that some ecu updates, such as the Kleemann, on regular c63 makes the car equal to the stock p31 package. I am not sure thow that it is true for all
ecu tunes and definitely not true if one would do other upgrades such as headers and what not. It is hard proposition. One can get limited slip differential for 1.4k and tune the car for another 2k and be faster than stock p31 packaage at a lower price. But again one could get the p31 + imited slip if money were no object

_AMG_

The P31 is a beast. I really didnt think the upgraded internals, and higher hp output would make a difference, man was I wrong!

DD GT3 RD

if you plan on doing a blower maybe the forged internals will come in handy!

600whp S4

if you're going to spray the car or supercharge it get the p31. I like the fact you can get a built forged shortblock from the factory for 3K thats a steal

DuaneC63

And your factory warranty is still good. The MBZ ECU cannot be flashed via the OBD port hence it must be removed. Any MBZ dealer can easily check if this has been done. Any powertrain issues will not be covered with an ECU that has been modified.