Are tools available to do our own tuning? We'd much prefer to tune ourselves, then have someone else do it...

 

Glad I'm not the only one who thinks it's one of the scummiest industries there is.

 

I mean it's a flash-tune. It's just a matter of having the software/definitions file that will let you edit it. I would prefer to do my own too but as far as I'm aware none of those in the know offer that to the end user. Eurocharged is happy to do infinite retunes via email, but like I said it's been pretty vague as far as what can be changed. I'm extremely happy with the performance I am getting out of the tune Jerry sent me so I haven't wanted to step on any toes by digging into it too deep to see what I might be able to come up with on my own. I mean the traction light will flash angrily at me if I punch it from 50...and i have yet to even try the race gas tune. These things are incredibly impressive with the instantaneous torque delivery.

 

We tune the chrome ecu's on the 3/S often. But I guess no one will share their data /files so we can tune ourselves... Something to look into more I guess once we get our hands on one.

I really would prefer selling my spyder first before leapimg into something else... So time to get it buttoned up and listed... This should be fun!

 

Yeah, I had I believe the 2nd ever flash tuned Montero ECU on one of my cars way back before the Chrome days. Had to poke around and compare known definitions files for similar vehicles to the VR-4 .bin to try and find tables and parameters. Fortunately the important ones had already been figured out. I had a heck of a time back in the day trying to find more parameters on Subaru/Nissan ECUs.

I'm sure we could figure something out on these cars but I know how much work it is trying to do that from scratch...so I just went with what was available.

 

We had a Eurocharged tune on the 2006 S65. With the 5 speed transmission there was no transmission power limiter so the as-tuned torque was up about 15% over a wide rev band. It also resulted in about a 10% increase in Highway driving fuel mileage. Tradeoff was a decrease in fuel mileage when driving hard. If you want a greater improvement some tuners offers a service where they will send updated custom tunes if you rent Dyno time and have them log into the data.
I replaced the stock 275's with 285's on the rear and put 255's on the front.They fit on the stock wheels with no issues. This provided a surprising increase in traction.

 

Yeah and the gains on a 600 are even more pronounced since they are so much further from the torque limit/detuned to start with.

 

We own an awd dyno, which is why we would rather just tune ourselves. But if it's really just not possible, I guess it is what it is :/

 

There's a guy on here somewhere from overseas that was talking about his friend tuning it. I am sure there is some software available in europe or china that will do it.... it's just matter of figuring out what that is, how to get it, and how to work it without bricking your ECU.

 

Hmm.. I'll do some digging on that, thank you

 

I've heard some references to what I believe was a handheld flash tuner called my genius or something. Obviously it has evolved to laptop tuning these days but I don't know what the editing software behind it all is.

 

Will these cars take to an afc? I know some cars, regardless, will override any piggyback tune... Is that the case with these? Or are piggy backs just frowned upon by this crowd?

 

There's no maf. They have at least 5 map sensors that I am aware of. Duping them would be a nightmare.

 

There's no maf. They have at least 5 map sensors that I am aware of. Duping them would be a nightmare.

 

Ah... Well... That poses a problem. Lol

 

Guys Mercedes owners are sharper than the average car buyer and know what they are buying when it comes to warranties. A few years ago Chrysler offered a warranty when they were merged with diamler, that was about $3000 for 5 years /75000 additional miles of coverage . Plenty of people in the Amg forums got $20,000+ worth of warranty related repairs out of Chrysler , till they stopped offering the warranty

These days USAA offers a good warranty without the typical shady bs

So while warranties generally are nothing but shady companies and frustration from Denials, Mercedes buyers are more intelligent and have been able to find the good warranties

 

+1 on USAA.

Had 2 year warranty through then when I bought the car, at a cost of $3K. Never an issue with a claim. Dealership service writer was impressed.

 

USAA is phenomenal to work with in every aspect. But they seem to be the exception in things like this, unfortunately.

 

I may have misrepresented a bit. There are 5 pressure sensors, but I believe most of the fueling is controlled by one of them and the others are mostly for error-checking purposes or minor adjustments. There's one in the manifold, one at the intercooler outlet, one in each bank airbox (post filter), and one onboard the computer itself for atmospheric reference.

The big gotcha with these cars, I think, is that if injectors really can't be scaled in the computer then we would hit a brick wall somewhere around 780hp crank HP if everything was linear. Not the end of the world, that's pretty good, but it's not the whole picture. I'm not sure it is linear. From what I've been able to find, the fuel pressure is fixed at (if I recall correctly) 55psi, regardless of intake manifold pressure. The fuel pump controller has no knowledge of boost pressure, and there is no regulator up front, just a relief valve in the fuel filter and pressure is maintained by the pump controller through pump duty cycle via feedback from a nearby pressure sensor.

So in my mind, the scaling in the computer has to adjust for higher manifold pressures by assuming progressively lower and lower effective fuel flow. I mean if we're 55psi rail pressure and have 25psi of boost, that's only 30psi across the injector. Which means our 340ish static flow @43.5psi injectors become 280s. 280x12x60/1000=201.6 liters per hour=53.25 gallons = 323 lb/hr * 12/60 = 64.67 lb/min of airflow capability at typical 12:1 AFRs, or only about 650hp to max out the injectors at safe AFRs, or a bit over 700 even at extremely aggressive AFRs typically reserved for naturally aspirated vehicles. My scratch pad math seems to line up with the RC engineering calculators @ 100% duty cycle and .50 BSFC (which is 12:1 AFR). Since I know a lot of people don't like to go over 80% or so injector duty cycle and I'm assuming you and Hans are in that group...that means you are basically going to max out this car's "safe" potential with just a mail-order tune from one of the vendor's, and basic intake/exhaust improvements.

I don't see any easy workaround...I mean we can pretty easily increase fuel pressure to improve flow rate, but if there's no way to tell the computer that you've done that, then it's going to hit fuel cut (if that's how Mercedes ECUs respond to a calculated need in excess of 100% duty cycle like the 3000GT ECUs do). I think the trick would have to be to scale the MAP sensor signal like you would with an AFC, but it's going to be a trickier proposition than just a fixed % correction since the ECU is making much more complicated calculations based off that value (changes with IAT, RPM, etc) than it would a mass air flow signal. I don't know if there's a device setup for doing AFC type stuff with a map sensor/factory speed density type tune but there may well be something out there.

The other obvious solution is that once we hit the limits of the stock system, any additional power would need to be added via means the computer doesn't know or care about/have any control over. Basically, through wet nitrous.

 

It's a lot to get familiar with. And will he easier once we get our hands on one. At that point, I'm sure Hans will dive in head first, as usual. �� that's when it will get fun
Haha

 

Would love to pay you guys a visit and show you around the car/what to watch out for in-person before you go shopping. Not to mention show you what they can do with a tune, lol...I should be very near the lower end of those theoretical limits I am talking about. But I don't get out east very often...even less often by car. If you guys ever get out this way for anything I certainly wouldn't mind driving within a few hours to meet you though. I'm about as central as it gets, lol. Wichita, KS.

 

With the kids now, we don't travel those kinds of distances anymore on a whim.

We'll get our hands on one soon enough. Hans seems to be just as excited as me about getting one of these... He's already trying to talk me into letting him drive it once in a while. Hahaha

 

Don't ever let him drive it. You'll end up with two of them that way. Just tell him it's actually way slower than you expected, but it's an awful nice/comfortable car so you want to keep it anyway.

 

He knows my bluff. Haha

He already said the second we get it home, it's going on the dyno for baseline numbers. Can't say I've seen him this excited about another car. Should be a fun time!

 

My best advice would be that it's definitely worth paying a premium for one that doesn't need any attention at all. I looked at several before finally buying mine, and you definitely can't judge these books by their cover. The majority of owners/sellers of these cars aren't mechanics and won't know about developing issues or things that might need attention until major symptoms are present so the ones for sale for $20,000 that are beautifully detailed and look flawless and come with a stack of receipts from the dealer may not necessarily be all that it appears. The car I ended up with was not the cleanest car I looked at, but it was well-maintained by an independent shop and was up to speed on a lot of things that some of the more pristine and dealer-maintained cars were not.

The biggest single thing though would be trying to buy one that's already had both coil packs replaced, with new spark plugs. You'll want to see receipts or verify that the end of the part number on the coils is a later revision (I believe Q6 is the newest, original is Q1). That's easily $3,000 in parts plus a lot of labor. Changing plugs would get you familiar quickly with how these are put together, but there are lots of delicate things that can be easily broken in the process even if you are extremely careful...including the coil packs themselves (delicate wires inside that can be damaged if the coils are tweaked at all during removal/install...so changing plugs is risky business...fortunately they are gold-plated contact NGK Laser iridium plugs so it's like an every 100k thing). I purchased mine with original coils, but had done enough research in advance to know I needed to factor the replacement cost of those into the price of the car, so I ended up negotiating down almost $6,000 from the original asking price (which was too high anyway, so maybe only $4,000 off from where it should have been priced) based on that and other maintenance items. Also a good idea to make sure there are no fluid leaks or seepage anywhere, particularly ABC. Motor mounts are an engine out operation if they are the older design, and still a very labor-intensive repair even if they are the revision, so if you run into a vibratey one, take that into account. I believe most of the 05+ had the newer style mounts to start with but who knows. Other than those things, most of the normal maintenance/things to look for is pretty normal.