GT/C192/R192: GT55 Renntech tune for sale
Member
Joined: Jan 2015
Posts: 93
Likes: 13
From: Florida
18 Benz C63
After a few days of having it now, I’ve had no issues whatsoever. I’ve put it through different paces and modes. I think they are totally full of sh*t when they say it’s VIN locked. Also, it’s really bad business of them to tell the people they sell it to for over $3k that’s it’s useless but hey I’ll give you a deal on a new one to make more money on them. Lol. As for how it feels, there is a slight difference but nothing spectacular. It’s definitely not worth the $3k they ask for it. Just my two cents though. This came out of a 25 GT55 that was purchased mid year of 25 and put into my 24 GT55.
Newbie
Joined: Apr 2026
Posts: 1
Likes: 0
2025 AMG GT55
@Clemtigr1 So what happened in the end? Did you test/sell it?
Junior Member
Joined: Feb 2025
Posts: 61
Likes: 7
Questions on Renntech RPM upgrade
For those who have installed the Renntech RPM upgrade, I have three questions (I have a 2025 GT55 Coupe):
1. Was there a significant hit on mpg?
2. Any pinging from the engine on 93 octane or higher fuel?
3. When you install the bypass plug, is the factory ECM still connected and reading from the various sensors that the Renntech plugs into? If not, doesn't that then throw errors?
1. Was there a significant hit on mpg?
2. Any pinging from the engine on 93 octane or higher fuel?
3. When you install the bypass plug, is the factory ECM still connected and reading from the various sensors that the Renntech plugs into? If not, doesn't that then throw errors?
