Transmission Tuning!
Member
Joined: Nov 2021
Posts: 222
Likes: 111
AMG GT C Edition 50
No, and I haven't considered it. I love my transmission as is. The Renntech website description seems void of details and high on price to me. Looks like a typical up-sell to me. Let me know if you find input that says otherwise.
Member
Joined: Nov 2021
Posts: 222
Likes: 111
AMG GT C Edition 50
I have no doubt that by hacking the software, tuners can get the shifts to be a bit quicker. What I'm skeptical about is the promise for faster shifting, while also lessening the stress and torque on the system. There are laws of physics, and there are laws of marketing. I think the latter are winning out in most instances when it comes to TCU mods. Personally, unless I was using my AMG GTR specifically for the track and money was on the line, I wouldn't mess with my TCU. In the most aggressive settings I find the shifts to be more than adequate. Certainly better than I could ever do with a manual transmission and all of the milliseconds saved don't add up to justify the potential downside. My two cents.
MBWorld Fanatic!
Joined: May 2008
Posts: 2,524
Likes: 1,007
From: Overland Park, KS
‘24 BMW iX M60
I have no doubt that by hacking the software, tuners can get the shifts to be a bit quicker. What I'm skeptical about is the promise for faster shifting, while also lessening the stress and torque on the system. There are laws of physics, and there are laws of marketing. I think the latter are winning out in most instances when it comes to TCU mods. Personally, unless I was using my AMG GTR specifically for the track and money was on the line, I wouldn't mess with my TCU. In the most aggressive settings I find the shifts to be more than adequate. Certainly better than I could ever do with a manual transmission and all of the milliseconds saved don't add up to justify the potential downside. My two cents.
The DCT in the car is excellent imho and runs a very, very close second to the Porsche PDK unit which is widely regarded as the best on the market. The shifts are responsive and are totally appropriate for the mode the transmission is in. Anyone who thinks the shift algorithm is deficient needs to place it in Race and head to the track; it’s sublime even in ‘D’.
If the tunes remove the torque limitation in the early gear sets in order to try and make the driver feel more ‘connected’ somehow; (and I’m not saying they do), then there’s a lot more stress being applied to the transmission.
If you’ve gone to a high power build in the engine and have had the transmission modified with upgraded clutch packs; gear sets, etc. then an appropriate TCU update makes perfect sense; just not for an OEM or Stage 1 ECU tune . Again, just my opinion.
Senior Member
Joined: Mar 2021
Posts: 279
Likes: 124
From: Indiana
2015 Mercedes S550 Coupe
I have used my GTR before i got stage 2 tune with downpipes and it used to shift seamlessly.. but it’s different when u have a stage 2 tune, stock tcu tune feels slow and not seamless it was before..
i do not have a tcu tune but i am definitely interested in getting it done, would be gr8 to have that same seamless shift like before
i do not have a tcu tune but i am definitely interested in getting it done, would be gr8 to have that same seamless shift like before
Here is my experience with Weistec TCU on GTC Stage 1 (About 640-680 HP, depending which tuner or dyno you want to believe):
Weistec claim that they increase the torque limit – Probably. However, I don’t think it’s possible to verify by "feeling it" with engine producing lower than… 800HP?
They claim that the shift is faster and firmer - Unless my brain can process a fraction of a millisecond shift differentials, I can’t say it's faster. Maybe just negligibly faster. Firmer? I think my imagination is telling me that I hear a stronger clank when shifting. It probably is, but not noticeable to the “unaided eye (ear)”.
One thing Weistec stated: “they do not change shifting points”.
It is very difficult to tell if there is any improvement. By the time I sent my original TCU and got it back, I already lost perception of the speed and noises of shifts make in race mode. Again, hard to tell without specialized equipment.
The bottom line is that I haven’t seen even a fraction of a second lap time improvement on a racetrack I frequent often.
I reverted it to stock and maybe reconsider reinstalling the tune when and if I decide to go to stage 3.
Weistec claim that they increase the torque limit – Probably. However, I don’t think it’s possible to verify by "feeling it" with engine producing lower than… 800HP?
They claim that the shift is faster and firmer - Unless my brain can process a fraction of a millisecond shift differentials, I can’t say it's faster. Maybe just negligibly faster. Firmer? I think my imagination is telling me that I hear a stronger clank when shifting. It probably is, but not noticeable to the “unaided eye (ear)”.
One thing Weistec stated: “they do not change shifting points”.
It is very difficult to tell if there is any improvement. By the time I sent my original TCU and got it back, I already lost perception of the speed and noises of shifts make in race mode. Again, hard to tell without specialized equipment.
The bottom line is that I haven’t seen even a fraction of a second lap time improvement on a racetrack I frequent often.
I reverted it to stock and maybe reconsider reinstalling the tune when and if I decide to go to stage 3.
Last edited by G. P; Mar 30, 2023 at 07:17 PM.
Trending Topics
Super Member
Joined: Feb 2006
Posts: 669
Likes: 81
S63 COUPE M157
Same experience here, did Weistec TCU on my M157 S63 Cp. and if there was any improvement at all, it would be like 10%. By Dragy acceleration measure, no improvement. The tune costed me 2k USD. Don’t really know if I needed it at all.
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
MBWorld Fanatic!
Joined: Aug 2012
Posts: 1,218
Likes: 315
From: Pearland, Tx
2020 AMG GTC Coupe & 2018 Macan Turbo
I have no doubt that by hacking the software, tuners can get the shifts to be a bit quicker. What I'm skeptical about is the promise for faster shifting, while also lessening the stress and torque on the system. There are laws of physics, and there are laws of marketing. I think the latter are winning out in most instances when it comes to TCU mods. Personally, unless I was using my AMG GTR specifically for the track and money was on the line, I wouldn't mess with my TCU. In the most aggressive settings I find the shifts to be more than adequate. Certainly better than I could ever do with a manual transmission and all of the milliseconds saved don't add up to justify the potential downside. My two cents.
Super Member
Joined: Dec 2014
Posts: 737
Likes: 211
/////PRO
I think like anything, boils down to the experience of the one doing the tuning. By experience I don’t mean someone that has done in quantity, but someone who has superior knowledge levels of the platform, the factory TCU tuning, what opportunities exist within it for improvement, and how to properly, and safely, extract that potential.
Junior Member
Joined: Mar 2025
Posts: 29
Likes: 8
heres sound clip of what mine sounds like now. Windows are up and its on my
iphone. Renntech mods sound check let me know what you think
iphone. Renntech mods sound check let me know what you think
