Hello,
I am considering an ECU tune in the near future for a 2018 C63S, and I wanted to open the debate about who has the "best tune". I know there are a lot of options out there, but I am really only considering Weistec, RennTech, or EuroCharged. I only want a "Stage 1" Tune, nothing crazy. I want excellent drive-ability and OEM-like reliability above all. My car must also remain emissions compliant because I live in "Cali-rado"

As far as getting the tune itself, since I'm located in "Cali-rado", I understand it will likely be either an OBD dongle, or an online session with an OBD adapter (unless someone knows where I can get an in-person dyno tune from one of these companies locally, near Denver, CO). As for factoring in the costs of buying some tuner's handheld dongle or programmer, I do already have a Tactrix 2.0 OBD dongle that has never been used, and my understanding is that some tuners can use that via remote session through my laptop. I also have BenzNinja's whole set up with a StarConnect C4, and Vediamo and Xentry, but I'm not sure a tuner can use that software and device(s) for remote ECU / TCU "tuning".

I might also consider a TCU tune for the 7-speed transmission in my car if anybody wants to weigh in on that too. Really just looking to sharpen / firm up the shifts just a little, and improve line pressure / clutch clamping due to the extra power from the tune.

Thanks in advance for sharing your opinions and experiences.

I thought there would be a lot of opinions on this... Not even a peep from the vendors....🤔

platforum isn't has hot as it used to be, i'm over on the glc63 page and its just a dead. Amazing platform for sure, will alway be loved, not sure how much of tuning has been done since I left in 2020. Regarding tuning and whom to go with.. seems like all the ots 3 tunes will yield you some more power over "s" models, it me its not worth the cost till you go flex fuel tuning or have more ethanol to tune and achieve more power, but that is just imho.

I'd recommend looking into what a tuner local to you uses and get something custom fit to your car instead of getting an OTS ("off-the-shelf") tune. That way you'll know it's safe on your car and be less likely to encounter issues, provided the local option is reputable.

I don't really have a "local option" (that I'm aware of) in the Denver, CO area. I agree that a dyno tune will be the most precise for my vehicle. But a local tuner probably does not have anywhere near the experience that one of the big tuners has.

That is mainly why I'm considering one of the "big 3" of the Mercedes tuners as I feel like their tunes are "safe" and tested, versus a local dyno tune trying to squeeze every ounce out of it and then backing it off a little to be "street-able" and safe for the longevity of the engine.

Renntech is by far the most expensive, Weistec is second, and EuroCharged is the cheapest. Weistec seems to advertise the biggest hp and tq gains, but I'm fully aware that is totally subjective and mainly for marketing. EuroCharged seems to be the cheapest option and fairly popular, I just don't see them as the "big name".... But maybe I'm leaning too much into the reputation that Renntech is built on (former AMG employee).... And I view Weistec as somewhere in the middle of Renntech and EuroCharged.

I was hoping for the opinions and experiences of people who have used these companies to help make the decision. My friend had a 19' GLC63S that was Renntech tuned, and it was fast, but it also encountered many problems over the year he owned it (causing him to sell it)... It needed new turbos, a new differential, and a bunch of new a/c parts, and eventually a ECM (which resulted in losing the Renntech tune). A MB dealership did all the work under warranty (luckily) and it is up for debate whether the Renntech tune and the additional power, and resulting abuse of the right pedal, contributed to the failures.... But it's just a piece of information for me to consider.

Again, I want it all... More power, but also reliability, and stock-like driveability... For the best price.
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Sure, from those 3 options I would choose EC.
If you wanted another option I would choose our Morendi option.
Think a transmission tune is a bit OTT for a stage 1 too.

I can just tell you from my experience, I have had a Eurocharged tune on my car for about 5 years with zero issues. At the very beginning, I reached out via phone and talked to them 2 times, Pre purchased to ask question about things like emissions and other questions. I never felt rushed talking to them, they answered everything i raised and more. After the purchased, they also were happy to spend about 30 mins helping guide me through the install via MyGenius. I always felt they I was a customer and never a burden. For that reason. Funny I came across this thread looking for a new tune for one of my new Mercers hoping for a Black Friday sale...

Best of luck with your choice regardless of what you choose!.

Cheers.
JP

@Quattrodude thanks for the input. That's the kind of experience I was hoping to hear about. That means a lot that you had zero issues and they treated you well. I do like that Eurocharged has a lot of locations. The closest one to me is in Texas I believe.