Mercedes Benz E-class E500... ECU remap!

If you follow my content on Twitter or STEEM you surely have guessed meanwhile that besides my interests in information technology, information security, crypto and AI tech I’m also quite an petrolhead.

Due to some misfortunes (two involuntary accidents in half a year) I had to change my rides twice this year.

From an Mercedes Benz ML 55 AMG to an

Mercedes Benz E550 wagon with an natural aspirated V8 engine and recently to an newer model Mercedes Benz E550 wagon with Bi-Turbo V8 engine.

Interestingly the M278 engine (Base) that is placed in my latest E550 purchase is closely related to the M157 engine which is the performance variant of this engine family that are used in many AMG cars. Main differences being bigger displacement and overall tune for higher performance.

It doesn't come as a too big surprise that the M278 engine has some very impressive higher tolerances in the basic 500/550 setups that are used in the E-class, C-class and other coupes/limousines.

So, if you’re looking for some gains in torque and power there are different options that can touch actually other parts or different in place tuning options.
Most effectively, without the need to spend 5 digit sums for a more aggressive tuning of this machine towards typical stage II or stage III scenarios (turbos, downpipe, intake, manifold, exhaust system, "big boring" (;-)) setups, you can push the envelope pretty impressively just by an ECU (engine control unit) remap/coding.

Why is this possible?

Well because of the very generous tolerances that leave plenty of upward room before becoming critical or even disastrous in the relevant motor parts, transmission, exhaust system and so on and because the fuel injection and turbochargers allow for it.
In my case the stock mapping of my M278 in my E550 is tuned for 600 nm of torque and 408 hp which in combination with the automatic 7g Tronic transmission already makes for an solid "sleeper" category car.

Of course many of the sporty, modern hatchbacks for instance, with also very "tunable" engines, would right out of the box already simply drive circles around my "soccer mom" wagon no matter how solid the chunky fellow unfolds his power right down from the rev cellar up to around 6k revs.

With a curb weight of around 1925 kg or 4243.9 lbs much of the "chunkyness" and power simply goes "poof" to move that kind of weight around.

But, especially as a used car - and I buy all of my rides used since a few decades because it's simply nuts to me what these things cost new (sticker price of my car must’ve been around 90 k € for example - it really combines much of what I am looking for in my rides:

• Active and passive security features. This always was very important to me and with the recent, unpleasant experiences I almost cannot emphasize this enough which is why this made the top of this list right here!
• High comfort (awe... the air ride in that thing alone is soooo wonderful),
• Room …not at last because we have dogs a wagon is essential to me.
• Aesthetics.
• Overall cost,
• ...and of course performance = fun! (sorry Greta...)

Of course there are some substantial higher performing models of this car available but they also come with hefty drawbacks imo.

Most of all the noise...

Yeah, I get it that some feel that they have to have that loud, nasty, deep sounding due to large displacement gargling to screaming sound at higher revs including the acoustic pressure sensations you can feel on your chest and the burbling and turbo waste gate hissing to either make heads turn and shake in disgust and incomprehension or to see those envy glaring eyes and wide smiles.

Confession… yep, I liked that too as a youngster and every now and then I still enjoy it to hear a nice V8 or V10 engine in all their glory.

But not constantly and for sure not in my daily driver not only because it would get on my nerves but also because I guess this is very inconsiderate towards everybody else.
This show off thing is so childish and annoying that I actually support that the police starts slapping tickets on the people that think they have to “bless” everyone with their straight piped or switch controlled flapped muffler monstrosities or even grounds them for good including tow cost and topping out pulling the registration until re-audit/inspection of their ear killer vehicles.

I remember the times when we had two beamers and a few bikes in our private motor pool. Sure, I mostly rode my bikes whenever the weather conditions allowed for it but when I had to take a car, I chose the BMW 328 I over the BMW Z3 M coupe because of exactly that. An deep, loud sounding exhaust system that made me smile in the beginning when the car was new to me and that simply was no fun anymore pretty quickly after that.

The 328I was just fine… it had 140 horses less than the M coupe but it was a joy to drive it especially for my daily commutes to and from work.

So loud isn’t my thing at all. Sure if you go fast on the Autobahn I don’t expect the car to be as subtle as an electro mobile but I do expect that you can have a normal conversation in the car while going 200 to 220 kph without the need to scream because the car is deafening loud.

The Mercedes E500 wagon does wonderfully in this regard in contrast to his “bigger” brother the E 63 AMG.

The riding comfort…

Another thing is the combination of wheels/tires and suspension which is pretty tough in the AMGs, mostly due to the extreme low profile tire/rim combination but also because of shorter springs in the suspension (20 to 40 mm).
Not so easy to have a really comfy ride in those when you can feel every little pebble on the street while the exhaust systems constantly screems at you.

So… the 500/550 models of the S212 series E-class combine the best of both worlds imho. Comfort and performance and even regarding the little lesser performance of the engine a nice and balanced ECU remap can handle that just perfectly.

…and that is exactly what I’ve taken care of with my E-class.

Beforehand I had done some research into different options starting from add on tuning boxes that are fitted between the injection rail cabling, the Oxygen sensors and the ECU. Nice solutions it seemed that are kind of plug and play but have some ugly disadvantages when looked at closely.

There are a bunch of these out there but the most prominent being Racechip I guess.
They even come with an mobile app integration where you can dynamically change your setup/preferences in regards to different performance and comfort settings.
And they play a little with the throttle by wire... they make the reaction of the car more responsive to your gas foot so to say.

But the really weird thing is that due to all the dynamically adjusted parameters in die ECU the performance gaining effects can wear off quite simply because what you ask from the fuel injection, turbochargers and so on is then possibly readjusted in the ECU and the control unit of the transmission as well.

I read some reports about solutions like that where the performance gains turned into an effective performance loss after 1 to 2k kilometers because the ECU and the transmission control unit “learned” to adjust for the fony inputs it gets from the “in between” placed tuning chip.

These kind of solutions were not for me also because there is no way you can get a car with such an “adjustment” through the security inspection. Resulting from this if you use such an add on system you won’t have a valid registration and therefor no insurance coverage in case something happens. Quite a huge risk one would have to accept, when it comes to an accident, that could easily make for some massive headaches and even push you into financial ruin.

No chance I would use one of these things without proper paperwork, security inspection, adjusted registration and appropriate insurance coverage.

This is why I chose an complete ECU remap that has an “TÜV Mustergutachten” (security inspection assessment report) that you can use to adjust your registration and insurance.

This ECU remap/recode also addresses the needed parameter changes in an holistic approach so to say rather than just mess with certain performance relevant adjustments in an unrefined, “brutal” way, that will only lead to an “wear off” effect because the ECU adjusts for the “weird” deviations in the parameters while in reaction to that it’s compromising the overall performance of the vehicle.

But even this “holistic” recode of the ECU will be restrained by the control unit of the automatic transmission in some constellations which simply protects the transmission from going “poof”, hahaha!

I mean we’re talking some serious numbers in regard to the performance gains that are achievable with such an ECU remap/recode and torque wise the transmission is built to take up to 700 to 750 nm max and for long term reliability Mercedes Benz stays under these higher values with around 600 nm just to go sure that these transmissions do their job reliably for 200 k kilometers and more.

This is a general thing you have to keep in mind with such an tuning configuration intervention. If you constantly use all the horses and the torque at 100% that are available you will reduce the engine and transmission lifespan significantly.
On the other hand due to the gains in torque especially you can effectively drive the car with lower revs and actually even save on gas in such an setup… at least in theory.

Ok, so here are the numbers!

• The baseline for my car is 408 hp (300 kW) at 5,250, 600 Nm (443 lbf⋅ft) at 1,600–4,750.
• The target values were 520 hp and 700 Nm torque.
• The actual, dyno’ed (measured) values are…

• 529 - 551 hp and 847 Nm torque.

What I can say so far after driving the car in mostly wet conditions on country roads and inner city streets and just a few highway miles…

It drives and handles nicely! I was a little concerned that the higher torque would possibly lead to a lot of slippage especially when driving off from a full halt or on an ascent but it seems that the 7G tronic automatic transmission still handles the massive torque adequately without such negative effects.

I also thought that, due to the obvious earlier high boost pressure from the turbo regulation adjustments, higher power deconvolution could possibly lead to a harder controllable ride over all especially with the stability programs turned off. But as far as I can tell so far, the higher power unfolding is rather homogenous which makes this no issue at all.

Of course you have to account for this massive torque gain especially when accelerating out of corners and so on or you will drive sideways a lot like in a drift car. But if that’s what you’re after and you can afford the tire shredding that comes with it… well than this would be perfect for you too! Hahaha!

But again, this isn’t what I am after.

Most impressively I can say that when cruising with the car the overall ride became even more comfortable because you will hardly ever see higher revs than 1,000 to 1,300 rpm ever if just gliding along with traffic. The engine noises are actually reduced due to this low rpm cruising and I guess this will even show as well in reduced gas consumption.
But when you put the pedal to the metal… damn, all hell breaks loose!

The power gain shows throughout the rpm band and especially when accelerating from lower speeds up to 200 kph it never seems to stop pulling massively.
You could also do some adjustments to the transmission control box to allow for more torque to “come through” into the drive train but this for one will definitely be life shortening for the transmission and I guess it would make the whole thing much harder to handle. I for sure won’t do that though.

I’ll do an update some time in the future especially when the car gets back it’s summer wheels (right now sitting on Pirelli winter tires).

So overall I’m very happy with this ECU tune job and especially in regards to the “bang for buck” factor I couldn’t be happier.

Cheers!
Lucky