Posting this here to spark discussion, not an all out war...

This list was started over on the various WhatsApp W212 User forums I am active in.
I don't lay claim to which tune is better than any others. I leave that to the fanboys to fight over....

Do you guys agree with this list assuming the sole metric is getting you down the quarter as quick and as fast as you can for the least amount of money, safely?

I think this is what we settled on in our Whats App user forums...

$$$ $1000 to $2500
$$ $500 to $999
$ under $499

Listed in order of best ROI (biggest bang for buck)

$$$ 1. ECU tune c/w HPT to log data (depending on tune)
$$$ 2. TCU tune (depending on above, may be better served getting a TCU tune first)
$$ 3. Grippier Tires (rear)
$$ 4. Ethanol Sensor* (if running an Ethanol Tune, safety item, not performance)
$ 5. DeCatted Stock downpipes (improves flow using stock hardware)
$ 6. Rewire IC circuit to always on (simple rewire)
$$ 7. IC running distilled water w/ water wetter and aftermarket SMIC (upgrade the passenger side SMIC)
$$ 8. ECE billet Mounts (install once and done - saves on multiple OEM mount installs)
$$$ 9. Lighter Rims (lowers rotational mass)

*only recommended with an Ethanol tune - not needed otherwise

While spark plugs were not mentioned above, its worth noting that the majority of people with aftermarket tunes found performance gains with a 0.022 to 0.023 gap of their plugs.
While true for most, there was one instance were the gap was too tight. Moral of the story... don't overlook the importance of your plugs and the recommended gap and follow your tuners recommendations.

You'll notice a few of the more typical mods didn't make the list above. Within our group we have a good cross section of enthusiasts who have all these mods and more.
Based on our performance metric above we think this is the best way to spend your money on your car if all you want to do is go fast, safely, for the least amount of money.
In our opinion all other mods return varying degrees of improvement for the money spent, or our real world experiences just didn't match the salesmans performance claims.

I'm prepared to be proven wrong... but dyno graphs are a metric that doesn't mean much IMO. We like real world data logs and quarter mile slips to measure performance.

As a group of enthusiasts this list, while not exhaustive nor complete, does give someone insight into what their fellow enthusiasts deem worthy of their money.

How would you rank the top ten mods, and more importantly, why?

 

I think we mentioned something like this in a recent thread. I agree with the list. Two items I would insert: LSD for those who do not already have it (especially RWD) and intake spacers/hi-flow filter combo. Also, for completeness, I would include (a) upgraded turbo impellers, (b) larger turbos/injectors/hpfp, (c) methanol injection. Primarily for everyone to understand the relative order.

 

Good call on the LSD... thanks for the add... the majority of our group are running AWD, so its not on our horizon... if your car is not equipped with a LSD, then it should be very near the top of a mod list.

 

does it make that much difference, Brett? Pretty sure I don't have an LSD, but my car leaves two long 11's now when accelerating from a stop since TCU tune...

 

if your car leaves two marks on the street, you have a LSD; an open diff would leave only one.

 

that would be interesting as it's an E550 and they don't come with LSDs...I wonder if the previous owner had one installed??? Guess I need to jack up the rear and find out!

it leaves 2 marks, very solid, for a long way...lol maybe 30-40 feet?

 

Agree with @BCP about 2 marks. But just to make sure, raise the rear to test.
EDIT: You are lucky. It does sound like an aftermarket LSD install because MY12 E550 did not allow Option 471.

 

oh yeah, I know. thanks though!

 

sounds like it received a lsd at some point.

 

First, I would lump ethanol sensor as part of the cost of a tune, as associated hardware, and not as a separate item. I don't feel it deserves a separate ranking or mention at all.

Discussion: You guys nailed it on the head of it not being required unless running ethanol. To run flex fuel, it's an absolute necessity as the ecu on it's own lacks the capability to interpolate fuel content on existing hardware. For all other ethanol tunes (e50 or e85 tunes) agreed it is useful if you can't account for the ethanol content of the fuel. However, its accuracy is only so so as it's actually rather easy to give it a false reading. A high water concentration will give a false reading.

Second, split cooling is missing from the list. I would rank it near equal to your #6.

Discussion: Earlier generations of W212s did not have a divorced cooling system. Relatively easy and cheap to do. Even MB finally figured gave this a head nod by finally doing this on the later cars.

Next on point #7, I agree with the SMIC but argue that one is condition dependent concerning running distilled water with water wetter. I feel that #7 ought to remove mention or using either water or coolant as it's really user/builder preference.

Discussion: The water vs. coolant debate/ discussion is not by any means new. It really depends on what you're doing with the car and the conditions it's going to see. Yes, water with water wetter cools faster. However, coolant has a higher boiling point and far more resistant to freezing. If all you're doing with the car is 1/8th - standing mile drag racing, sure/maybe. For anything less than a full out purpose built dragster, I have yet to see a dramatic and consistent difference between the two to even make it mentionable. If the discussion is "well it's cheaper than coolant," then sure why not. Otherwise, it's really not worth going out of your way to do.

Finally what's missing, I'm surprised methanol injection is not on the list, nor any sort of airbox modification.

Discussion: Less restrictive airflow in general always shows a measured difference, as does increasing post-turbo air density. Granted, for the methanol tuning/dialing it in is essential. Cost to performance, I'd say moderate and would rank it above engine mounts assuming you'retapping the pipe yourself vs. Buying a modified pipe setup. Airbox mods, there are cheap(ish) enough options including making your own (provided you have some know-how) that it could be considered either $-$$ (in fairness, I'm making an educated guess on the metrics used to make the cost/performance ratio) that I would rank it above methanol injection.

 

Please clarify this point as I read conflicting accounts. According to EuroCharged, their flex fuel tune allows ECU to calibrate for any Ethanol blend "almost instantly." The tune does not require any additional hardware or the sensor, but it helps to predict performance.

 

wouldnt it leave two marks if BOTH wheels are equally without traction?

 

This condition of both wheels with equal traction is possible in ideal conditions or when suspended, but in practice (as in this scenario) wheels have unequal traction... Miniscule things like road imperfections, vehicle weight (driver on one side), vibrations, tire wear, tire inflation, etc., make open diff direct torque to one wheel. As long as the spin and conditions remain, open diff sends torque to the same wheel. Popular countermeasures include drop of throttle to reduce torque to the point of regaining traction. Another approach is to apply brakes on the spinning wheel to emulate traction to either (a) attempt to slow the wheel to regain road traction or (b) make the spinning wheel drop rotation below the opposing wheel to trigger open diff redirect torque to the other side. Two marks are only possible on a non-open differential (LSD, welded, etc.).

 

WAIT!!! YOU DID IT!!! YOU BUM YOU DIDN'T TELL ME!!!!! ok I'm going to flood your IG dm with questions!

 

Is your 550 not a 4matic? I thought all the biturbo's were 4 matic that's why we don't have LSD.

 

As a disclaimer, going too deep into this discussion I feel is off topic to the thread itself. If you want to get philosophical about the pros/cons/limits, we should start a new thread.

Not too much to clarify. The ecu can only automatically adjust for what it can see. As is our cars can see knock, fuel pressure, coolant temp, and afr both pre and post cat all with a limited degree of resolution. Based on those sensory inputs our ecus will adjust within a predefined set of parameters and thresholds seamlessly. Anything outside those limits/thresholds become very obvious very quickly given the aggressiveness of MBs engine protections. This all happens within milliseconds.
The car is otherwise blind to fuel type and content, meaning it has no way to tell what fuel it has before it reaches your engine cylinders and combusts it.

Here's an article by Innovative that goes deeper into flex fuel tuning, including without a flex fuel sensor.
https://innovativetuning.com/e85-eth...cons-concerns/

 

Thanks for the info. Agree about off-topic, but noticed something that challenged what I got from EC (about the sensor) and had to ask.

 

With a LSD, yes. With an open differential, no. That is the function of a limited slip differential -- to send power to both wheels. An open differential, sends power to one wheel, typically the right rear in a rear wheel drive application. The limited slip rear sends power to both wheels while allowing the inside wheel to rotate at a different speed in turns to make it more streetable than a spool, which locks both wheels together, sends power to both wheels but the inside tire turns at the same speed as the outside tire in turns which leads to increased wear and often squealing from the inside tire. The spool is more durable but many consider it less streetable .

 

I don't know...given the same rolling resistance and the fact that the surface was in good shape, nice and even, I think it COULD spin both tires with an open diff. I haven't had time to check yet, but I'd be willing to bet that my car does NOT have an LSD. Hopefully I'll have the time this evening to check it out, if it's not raining still...I'll post here for sure when I find out.

 

6. Rewire IC circuit to always on (simple rewire)

Hi all, can anyone tell me how to do this please?

Many thanks!

Trev

 

That is not how you find out if you have a LSD.

 

Not sure where I said that is how you find out, but okay....obviously there are actual methods for finding out, but nowhere did I say doing a burnout is one of them. Thanks.

 

There is little challenge to the list. Perhaps, some additions. The next step could be to rank-order the top options for each.

 

Trey, Its as easy as pie....
What the mod does is bypass the solenoid to provide power to turn the IC pump on continuously when the car is running.
Currently, the stock IC circuit doesn't open until 114°F I believe.

The solenoid we will be tapping into is the square one just left of the coolant reservoir (split cooled W212)

Step 1, lift the solenoid off the cradle, flipping it over to splay the four wires a part. You are looking for the brown/blue wire depicted here...



Next, you want to remove some of the insulation around the brown/blue wire....



Taking about a 1 ft length of similar gauge wire, splice the new wire onto the exposed wire... solder the wire to ensure a tight connection and then wrap with electric tape and fiber tape if you have it available... this pic shows the wire connected prior to soldering.



In the picture above the wire that was attached came equipped on the other end with an eye. The image doesn't portray it that well, but this is attached to the solenid wire on the other end.

Underneath the solenoid cradle, on the passenger side strut mount you will find a convenient ground point...



In this image you will still see the exposed wire prior to us soldering and taping the connection. The other end gets attached the ground location noted here with the wrench on the nut.

With all the wiring in place remove the engine cover exposing the IC coolant reservoir in front of the ECU. Open the cap.

If all is configured correctly, the simple act of opening the car door with cause the pump to turn on and start circulating coolant. This will be evident by noticing flow in the IC reservoir.

Put the cap back on and re-install the engine cover....

Now, whenever you are driving the car, the IC circuit will be continuously on, helping to reduce IAT temperatures...

On the highway I noticed a very respectable 15-18 degrees above ambient. It was 90 degrees out. I'm keen to see how much an improvement there will be in the cooler months.

Good luck with your project... On a 1 to 10 scale for complexity... this is easily a 1.

 

Many thanks!!! that's a great write up, really appreciate your help! 👍👍👍

​​​​Cheers
Trev.