scrapaholic

I have an '18 C63s on order, due to arrive in a couple of weeks. Coming from a JB4 tuned M4, which was the best damn car I ever leased. The appeal of a piggyback for me is resale, as I lease a car every 3 years vs. a flash that's one and done. Also, software upgrades can be performed on the car without flash wipeout, and firmware/functionality can be updated at any point with a piggyback. I am leaning towards the Dinan at this point...just wondering if there is a clear reason to go flash. Appreciate everyone's educated thoughts.

Luis Tellechea

Im curious as well. i was told that the piggyback increase the boost pressure on the turbos while the bench flash does not. If this is true wouldn't a tune that does not increase the pressure be safer? This was info that a vendor told me, not sure if its true.

Also, what I do not understand is the piggy back needs about 4 hr of labor to install (based on dinan) while the ECU bench flash is the same amount of time (4 hrs) to remove, flash and reinstall. shouldn't the piggyback be less time and easier? seems like its the same time to remove the ECU.

I hope vendors chime in.

msd3075

This isn't directed at the OP but instead at all the resulting misinformation that hopefully this helps prevent.

Both a piggyback and a flash tune increase turbo boost, but they both do it in different ways.

A flash tune simply re-writes the stock parameters within the ECU. You are basically telling the engine/turbo/fuel system/etc to operate differently that what the ECU came with stock. This includes increasing boost, changing fuel mapping characteristics, and any other thing that the ECU is able to control. Each tune is different, so each with adjust these according to whatever the tuner wants to change. Anyone that looks at these parameters will see that they are not stock (ie if the engine runs 18 psi boost stock but is bumped up to 25 psi with the tune, the logs within the ECU will show that it's running 25 psi boost).

A piggyback does basically the same thing, but it does it in a stealthy way. Instead of re-writing the code within the ECU to adjust all the parameters, it instead intercepts the signals from the sensors within the engine, alters these signals, adjusts them, and then sends the altered signals to the ECU. Given my same example above, the piggyback with intercept the signal telling the ECU it is at 18 psi boost and adjust it so it says it's only at 11 psi boost. This means the ECU then ups the boost 7 psi to what it thinks is 18 psi total but is really 25 psi.

The advantage of the flash tune is that you are hardcoding directly into the ECU exactly what you want it to do. No altered sensor signals. No trickery. Just exactly what you want it to do. It also means that since the ECU is reading real-time and accurate data, "theoretically" you have a safer situation since the fail-safes and warnings should happen as needed since there isn't the possibility that a piggyback is altering what's really going on.

The advantage of the piggyback is that you can "theoretically" install and remove it at your leisure without any permanent changes to the ECU.

I've never been a fan of piggybacks simply because when you get down to it they are just a programming lie. The ECU thinks everything is hunky dory within its set parameters when it's not. With how complex engines, fuel systems, turbos, and all the ancillary systems are these days, everything needs to work in unison, and to me a piggyback is directly counter to that logic.

There's a place in the market for piggybacks, don't get me wrong, but it's no different that that there's a place in the market for cheap liquor.

Luis Tellechea

so based on your response, could you conclude that dinan is warranting the cars, because if you have failure they will instruct you to remove the piggyback and since the ECU was not tampered with then MB would not know that the ECU was being tricked thus fixing the problem during the warranty period? maybe that is why they may say they warranty within the manufacturers warranty period, because after that they dont want to pay for repairs

DinanCars

We will never instruct you to remove the device to go in for repairs to "pull one over" on the manufacturer. We encourage you to not hide the device. There is no need to since we back the warrant. We offer the factory matching warranty because we have engineered and tested the product to perform within the abilities of the vehicle and not cause issues. Simply put, we stand behind what we put out.

Besides, on the C63 the removal would be just as long as the install (~4 hours) and no one wants to do that over and over again. Well, maybe those that REALLY REALLY like working on their car. =)

Luis Tellechea

ok, no problem.

Can you elaborate on the OP question regarding your piggyback vs the ecu flash? also why is tricking the computer better than remapping the ECU?

DinanCars

A PROPER flash is superior to a piggyback. There are no arguments there. I emphasize PROPER just because there are a lot of folks that tune vehicles poorly and dont really know what they are doing which is just as dangerous as an overly aggressive piggyback, if not more so, since you are altering the base programming and the fail safes directly.

The reason why Dinan has adopted the piggyback approach is simply because of our business model. The only way to flash tune these newer encryption systems is by physiically removing and altering the ECU. In doing so all warranty is void. Since we match the factory warranty this approach is not a viable one for us as we would then assume responsibility for the entire car (or at least anything touched electronically which might as well be it all). Initially on the BMW side after we went away from flash tuning due to increasingly difficult encryption we went full boat on the piggyback approach and produced a harness that DIRECTLY connected to the DME(s) so we could touch and control any and all signals coming and going from the DME(s). This effectively made those piggybacks as close to a flash tune as possible in the form of a piggyback. While effective the downside was that the harnesses were ungodly expensive (cost of V8 harnesses approached very close to $1k JUST for the harness). We learned a lot on those early harnesses though and slowly stripped away things that just weren't needed for a safe and reliable tune from a piggyback point of view and ultimately arrived at the current generation of minimized harnesses which go to specific signals while still providing the same output and drivability as the elaborate harnesses. Simply cheaper to produce and a better price to the end user going that direction.

All that said Dinan has not entirely given up on flash tuning and is always exploring ways to crack the encryption (BMW side specifically) but until a true OBD2 flash tune is a possibility it has no place in the Dinan product catalog.

scrapaholic

Appreciate everyone's constructive and informative feedback. Dinan, could you give some insight into your development aspirations on the updated firmware side of the tune i.e. multiple maps, guage hijacking, etc. and relative timeline. One of the aspects I liked about the JB4 stage 3 tune for the S55 motor on the M, was the ability to change maps and other aspects of the tune on the fly with steering wheel controls or via Bluetooth.

Gunsmd

The piggyback has benefit of providing more power without permanently altering the car. It also has the advantage of not getting wiped out if MB performs an ECU firmware update. Where the bench flash has an advantage is if you plan on doing sport turbos, downpipes and sport cats you can maximize the gains from these add ons. I recently did the Dinan and have been happy so far. I leased the vehicle so I was not planning on spending the money for upgrading the turbos etc. Also, the matching warranty gives you some piece of mind.

DinanCars

Unfortunately, anything I said would be simply speculation without any real basis in fact. Other then knowing the app is being worked on and will have some gauge / metrics displayed thats about all the information I know. The interactivity and "self-tuning" will be nowhere near that of of the JB4 though just because of warranty implications (end users doing stupid things and breaking their cars) not to mention emissions limitations when introducing a lot of self tuned variables. In regards to stages/maps we have no intention of doing hard parts for the Mercedes line (the items that historically drive additional stages in Dinan land) so I have to imagine that the tune you see now is the max setting and if anything there would be maps that downgrade it in intervals (much like DINANTRONICS SPORT).

The fact of the matter is we are still feeling our way around the brand a bit so its still a bit fluid and things can change pretty quick. Not to mention we are still ironing out the interrelationship with our sister company APR and how we can better help one another. We are similar but our strengths are in different things --- we are old school and are strong suit is hard part development whereas APR is very software and new-age tech related (their in house software/app development team is second to none). The thought has always been to intermingle resources to the betterment of both brands but how to implement that exactly has been cumbersome thus far.

Zelvy Carbon

I have a Powerchip, Not a Dinan, But still a chip.
Overall I am pretty unhappy with it, but it wasn't a huge expense, so live and learn.
I think the main issue is the chip can only fool boost. A proper re-tune can change cam timing, fuel, boost, the lot. So the entire way the car makes power can change.
I will go a proper reflash soon.

waisoserious

From what I understand they do the same thing, but a full ECU reflash has a higher ceiling because the cars computer has builtin safety features like [i.e. maximum boost 20psi]. A full ECU reflash would allow the tuner to completely bypass/rewrite those safety features. A full ECU reflash also allows you to instruct the engine to pump more fuel or air or both. In short a full ECU reflash has access to so many more features than a piggyback.

The same is not always the same with a piggyback. A piggyback has to work within the safety parameters and does not always allow the tuner to change the air or fuel mixture. Some piggybacks allow a/f changes, some dont. But most piggybacks generally just change the boost.

But both of these devices/methods change the boost. Generally a piggyback is what you would use if you were still concerned about the factory warranty. Many tuners offer their own engine warranty but it is not as comprehensive as the original factory warranty, and it is never nearly as convenient as just taking it back to the dealer for service. A piggyback can be removed and the dealer would probably have no way of knowing it was ever present. An ecu can be reflashed back to stock, but I believe there is a counter that notes how many times an ECU was flashed, thus telling the dealer an aftermarket tune was present.

Please correct me if I am wrong.

msd3075

My understanding from all the past discussion on here is that it's not so much a flash counter that tells the dealer that the ECU was tuned but instead logs within the ECU showing parameters outside the factory settings that will throw a flag. You can reflash the ECU back to stock, but the logs will still show all the parameters that the tune changed.

And I'm assuming having no logs is just as incriminating as tuned logs.

Strafe1

I just came back from my MB dealer, where they also have a performance division. They install Renntech and Weistec tunes and upgrades. They also tell me that as long as they do the install (they have 2 dedicated techs), all MB warranties remain in place. Does anyone have experience with either of these tunes? The dealer favors Renntech, for customer service and their close affiliation with AMG. Any thoughts? My plan would be catted downpipes, air filters, tune, and blow off valves.

AlexZTuned

Not true and I’m shocked they would tell you this. When I was living in Boston, I asked a MB dealership that’s an AMG Performance Center and RennTech dealer, if the warranty would remain intact. They made it very clear to me that as soon as they flash the ECU when RennTech software, the ECU warranty is void. Since th ECU is controlling all drivetrain functions, this essentially voids your engine and transmission warranty because of the modified ECU. I decided not to go forward with it for that reason.

msd3075

It depends on what exact "warranty" you are referring to.

All dealers are independent from MB and have nothing directly to do with MB as a manufacturer. They are all independent dealers that sell/service MB cars based upon their agreement with MBUSA. They do not determine how/where/when a warranty claim is approved; they just submit their findings to MBUSA for approval, and MBUSA tells them to proceed if approved.

Dinan, Renntech, and others cover issues with their own warranty, but it simply supplements where MB denies warranty claims based on the changes done by the tune. Some dealers are comfortable with this and all the resulting hassle it might generate. Other dealers might cower in the face of MBUSA. It all just depends on your unique situation.

Strafe1

There may indeed be some back channel talk between Renntech and AMG (or MBUSA) that would invisibly cover any potential warranty issue just like Dinan has with BMW. On the surface it seems like a trust-worthy venture since the work is approved and done by an authorized MB dealer and service center, with no actual or implied waiver of warranty, in fact, a statement of absolutely no change in warranty protection at all. However, they did tell me that if I opted for catless downpipes, I would have to sign a waiver of acceptance of responsibility as some aspects of the tune would not be predictable. Unrelated aspects of the tune would still be covered though. The service manager outlined the scenarios in which they would flag a VIN (certain tunes/tuners, and incorrectly performed mods to name a few), and that they have done so in the past. They went on to state that the mods they perform in no way change the MB vehicle warranty. Maybe they only share selected information when submitting warranty claims. I don't know. In theory, if the tuners have worked closely with AMG and operate within the safe limits of the engine and drivetrain, and if the installation is done in a certified manner, any warranty claim based on engine or drivetrain failure would not be the fault of the tune. Maybe its that simple. I've known these guys for many years, and when I had a previous C63 tuned by Kleeman, they performed A and B services on my vehicle, bypassing any ECU updates in order to protect my tune.
Your experience in Boston certainly raises a flag. But my experience with my dealer feels trustworthy. At best, I have a 100% iron clad warranty. At worst, maybe a have Dinan/BMW-like situation. At least I hope. Either seems acceptable to me. At first I was thinking Dinan piggyback. But I am now leaning towards the Renntech.

subzero05

what dealer do you use?. that's a pretty good deal if in fact true

Strafe1

I'm near Denver, Colorado

VFORCE09

Hi
that is weird that a Mercedes dealer would recommend Renntech when from what i have heard from some performance dealers here in Miami Florida is that Mercedes stop recommending the Renntech tunes because of to many blown engine complaints, one dealer is Mercedes Of Pompano that use to install Renntech

brad65ford

Sorry if this was asked aleady, do the piggy back tuners for these c63s need to ecu to be dropped down?

subzero05

brad65ford

So no need to pull the ecu down, that is very good to hear, its a ***** to get to. Assuming this attaches somewhere then then, looks like the same to clamps that go to the ECU when I had my ECU out.

subzero05

WellesleyGL

I have the Dinan piggyback and had it professionally installed. It's amazing the amount of torque it has now. Boost hits hard above 2500rpms. Worth every cent!
Kudos to Dinan for doing their homework.

http://www.eurotechmotorsports.us did the install in Natck MA.