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2009 SLK350
372 Posts
Appreciate where you are coming from Dave and respect your expertise. Unfortunately not all of us have access to someone with your skills so what may be an easy fix for you can turn into a nightmare for someone in my location. As an example of MB excess just look at the incremental speed computer controlled radiator fan when in practice a simple on/off switch does the job and can be fixed in any back yard. The MB fan at full speed is a noisy bugger too so some aerodynamic attention there would no go astray.

I will however say in my experience that Australian available aftermarket ECU's are excellent and can be dyno tuned to provide more power than stock with all the driving sophistication needed. They work off stock sensors and can operate devices like VVT and are continually being improved to do more and more. They are getting MB complicated :LOL:

**Premium Member '02 R170 SLK V8 5.0 & '00 SLK320
7,029 Posts
As an example of MB excess just look at the incremental speed computer controlled radiator fan when in practice a simple on/off switch does the job and can be fixed in any back yard
I think you have missed and just proved my whole point :(

Here is the maths I spoke of earlier ......
M113 V8 Engine, 2 plugs per cylinder, each one of those 2 plugs per cylinder fires 5 times per 2 engine revolutions, and each of the 5 sparks can be varied in it's timing ...................

8 x 5 x 6000 / 60 = 4000 variable Sparks per second at 6000 rpm ..............
Show me an aftermarket ECU that has that kind of computing power !! Show me a so called expert that can actually Map that, outside of the big guys like Kleeman etc. Why do Kleeman use factory ECU's on Mercedes ..............

Run a 5.0 M113 on a single spark at both plugs each cylinder i.e. 800 non variable Sparks per second and you'll be lucky to get 220 hp outta it, certainly won't get the broad V8 Torque spread i.e. you've now done the conversion and have a car that is no quicker than a regular V6 SLK320 !! The proof is in the dyno numbers and 1/4 mile times, not internet rubbish spouted by folks with a loud exhaust and fat tyres !!
That and the Cooling Fan and other PWM controlled parts is not excess, it is a decent, very efficient and reliable system.
MB pioneer stuff like this, other mfr's follow when patents expire years later.

The PWM controlled Fan is just one tiny and very simple refinement that MB have used for many years, and folks want to replace it with a switch 馃槶
If anyone wishing to do a conversion cannot fix one of those Fans, then they really shouldn't even consider doing these sort of conversions, look at the hassle the guys who use Hellcat Motors in older Muscle Cars have, they don't wire in bypasses and use aftermarket ECU's etc, well those who build refined Cars for road use don't. As I said earlier, a balls out Race car is a differnt kettle of fish, but it is not really streetable ;) I know, I built several cars like that and soon got fed up with them.

Yes I have a certain amount of knowledge and expertise, but how did I get that ......................
Mostly by working the issues that threw themselves at me and help from others who have far more expertise that I do, that is what Forums like this are for.

Also, when I first got my SDS it taught me a whole heap about Mercedes Benz Cars, (and many others who bought SDS have said exactly the same thing) (y)
Same also applies if you have a Land Rover you buy Nanocom, if you have Ford you get IDS or Forscan, Renault you get CAN Clip ........... etc etc etc

Now, someone living in Australia and on this forum ................
Simple, ask @nemiro to put them in touch with Andrew, I'm certain he can sort the Engine ECU and the TCU for a very reasonable sum via Internal Australian Postal service, someone living in UK speak to the guys in UK who know etc etc etc !!
Those 2 ECU's are the only thing that a half decent Mechanic won't be able to do. If the guy doing the job isn't a half decent Mechanic then the job is doomed from the outset :ROFLMAO:

Lordy, anyone can change the small Wiring plug in the Battery side Fusebox which is the only alteration needed for a Factory SLK V6 "Body" Wiring Loom !!
The Engine loom is plug and play.

The only reason I now know how to do it properly is because I got my hands dirty and just worked each issue as it reared it's head, hell, I'm no expert, I learned a helluva lot along the way though (y)
Ok, I'm all done here, if the job is worth doing, do it right, the rest on how to do it all properly is all in @nemiro 's or my own Threads on here.

*Premium Member
No SLK owned
188 Posts
I had the same thought as you, to ditch the stock electronics. I am far less concerned with the multiple sparks, as @Dave2302 is, as there are ways to handle that. A an electrical engineer, who has built a ton of cars over the years, mainly of the Chrysler persuasion, I was dismayed with the state of the wiring design and the electrical design in general. The wire coloring alone is enough to drive any pedantic engineer (like me) nuts! Chrysler, for instance, has used some of the same wire coloring for specific functions in all of their cars, since the 1960's! As new functions arrive, a new wire color is added, but it will be the same across all models and all ensuing model years. MB? Nah. We'll use the same wire color in four different places in the same car for four different functions, and then we'll switch it up on other models! Grrr... Then there is the whole coding scheme, SCN, and SDS in general. The needless non-standard relay modules, weird fuse boxes, goofy connectors and modules where they shouldn't be? What a flat awful system! I used to think Ford was the backwards one, and then MB made them look awesome!

My point here is once I started to dig, I realized that there are two approaches. Using what is all there, and suffering with it, or rewiring the car, just as you mention. My initial knee-jerk reaction was to break out the wire cutters, and give this car a haircut! A nice Autronic, FAST, or even a Megasquirt could do wonders! And they would. Getting the rest of the car to play along, even as simple as the R170 is, would be the challenge

(going to chase a rabbit here for a moment: ) Since I originally was NOT swapping in a MB V8, but rather a 600hp Chrysler 4 cylinder turbo (yes, indeed!), I mocked up the whole car's electrical system on the bench. I figured out how to make a Chrysler NGC3 ECU (from a 2007 PT Cruiser turbo) 'talk' on the CAN bus to the TCU. I was eliminating the SKREEM, but replacing it with the Chrysler version (called SKIM), but in time, I had it all on the bench, happily 'talking' and running the instrument cluster. Thank the Daimler Chrysler days for the rather straightforward cross-pollination that was happening there. Then the opportunity to buy the M113K happened, and the plan changed again.

Once I was back on a more 'solid' MB track, then it went back to those original two options. Use the MB stuff or go full aftermarket. After weighing the different approaches, the costs, benefits, etc, the math came out in favor of the modified MB gear, and the rest is history.

Now, here's the rub. I am a very long time tuner. I went back so far as to be the first to reverse engineer the code in several different Chrysler ECUs, and then modify them for racing applications. I was a beta tester to more than one of the mainline engine tuning companies, and provided engineering level support to one of the biggest names out there. I know tuning rather well. It was, and still is frustrating how closed up the tuning world is on the MB stuff. Why? There's big money in it. That puts a big green check mark in the aftermarket ECU column. What is a red X in that category, however, is the amount of work it will take to get the car to actually run right, and keep all of the other modules happy. Not saying it cannot be done (it can), but for less effort and money, the car is up and running. I will live with the rest.

2009 SLK350
372 Posts
Great stuff fellas, thankyou for your time and willingness to spread your knowledge.

Dave I would have liked to give you a drive in my Datsun 280Z with MoTec managed 420 WHP turbo VG30 DET. It was road registered so it could be driven to a race track, do some laps and then come home. Other than the race mods it was just as sweet to drive as any bought car. It's all in the tuning when a quality ECU like a MoTec is used, getting that power out of that engine with just 16 PSI boost illustrates that.

**Premium Member '02 R170 SLK V8 5.0 & '00 SLK320
7,029 Posts
All my comments relate to Mercedes Vehicle Technology including Engines, and Mercedes conversions ;)
Remember their technology on an Engine such as M112 V6 / M113 V8 was light years ahead of Vehicles from the same period, let alone vehicles from the 1980's like the Datsun 280Z and the Ford Cosworths, Corvettes, Firebirds etc etc etc that I was playing with back then ;)

In 2006, I drove to Le Mans with a very good mate of mine in his 1980's MB R107 SL Mercedes, fitted with an M113 V8 with a 722.6 Trans.

My buddy who owned that Car was also a Garage owner specialising in high end cars.
His workshops built it from the ground up ;)
That Car was built by professionals using the best aftermarket ECU / TCU available, and set up on a Rolling Road plus Track testing to give it's best by expert Tuners.

Yes it was a nice car, a quick car, certainly no shed and it drove very well, but it was nowhere near as refined / sweet / sorted / quick as the circa 2002 M113 V8 E Class from which the donor parts were sourced !!

We all have differing opinions, and I'm sure you are all as happy with your vehicular creations as I am with mine ;)
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