RENNtech logo NEW small v2b

Your input is important to us. Please provide your valuable feedback. Here are some testimonials from our clients:

I had RENNtech upgrade the software in my 2012 Mini Clubman S, Wow, what a difference! The engine pulls very strong right from a stop. I now have to learn to drive the car again without breaking the wheels loose even when already moving, this is with a 6 speed auto, Highly recommend the computer upgrade!

Frank G.

2012 Mini Cooper S Clubman
Posted By: RENNtech

Just want to follow-up, the difference in the car is amazing, it was hard to keep it below 80 on the way home.

Jim B.

E 550 Biturbo (W212)
Posted By: RENNtech
Hello Tomas,

Thank You for getting my ECM back to me Soo quickly. I was one hell of a happy camper when I walked into my office Friday afternoon and saw a box from "Renntech" sitting on my desk!

I had a family obligation up about an hours drive on pretty open and also some windy/hilly roads. I shot home dropped the ECM into my machine and off I went. WOW! The best way to describe the difference is, "The Inner Beast" in her has really been awakened and she still behaves Soo well. I had my wife with me so it wasn't just me and "The other woman". However I am extremely happy with the improvements you guys made.
Passing on a two lane road: She always had a great ability to pass quickly when crossing over thelines to get by "Grandpa Jenkins" and now when I punch it at 45 mph and blow around Grandpa-we come back into our lane at about 115mph. Before hand she was no slouch probably around 90-95mph.

I will have much more time to play with her over the next week and I will keep you updated. Please pass my gratitude on to the rest of your team. Not only did you guys deliver what you promised, you did it with class. You run an impressive operation, everyone I spoke with was courteous, professional and very informative.
Thank You Very Much Tomas. May you have countless days of continued successes.
Talk to ya soon. Thanks Again!


Jerry M.

2012 (C218) CLS 63 Biturbo
Posted By: RENNtech
Hey guys,

just wanted to post a quick review of my X5m and the recent mods; Renntech tune and Akrapovic catless downpipes.

I sent out my ECU(which probably takes 10mins to remove does have three tricky clips you have to unclip) once i took it out, sent it out to Renntech and got the ECU back, the day after they received it.

The car was completely different! Acceleration in the low range was much better, throttle response was def improved, and overall the car accelerated much quicker, in really wet conditions it def wants to break traction in 1st!
Three days later, I recieved my Akrapovic catless downpipes; got them installed which was a pretty labor intensive job the shop said. They kept the car overnight and I got it back the next day.
After getting into the car, i started it up and expected to hear a big difference, nothing, so as i drive away i floor it and you really hear a HUGE difference after 3.5k even with the M mode off, the car just opens up and it screams. With the M-Mode on its even louder, i couldnt imagine having exhaust, downpipes are def enough.

The sound is amazing! At redline it does have that raspy-pop that all of our X5ms have when you shift, so that def gets louder with the DP's. But overall the car just screams power, and i love the sound.

As far as performance just with this tune and the catless DP's the car is an animal! It flies! I mean the thing pulls, I i live in Seattle, and the car now literally breaks tractions when wet, in 1st and 2nd gear with just a twitch of the steering wheel you can lose traction if its wet lol I also own the e63 m6 v10 with a bunch of bolt on mods(headers, ecu, full exhaust, intake, pulleys) and even though the v10 does fly and has a crazy amount of power esp with the high rpms.

I can truly say that this x5m in a way scares me the fact that its such a big vehicle but flies like this is crazy! Once u open it up,it just gets up there so fast!!

I love it!

Thanks Jesse at Renntech for providing me with the ECU tune and akrapovic downpipes.

Vlad O.

Posted By: RENNtech

Thanks for the info! Loved the SL600 before an now it's fantastic. Love your products.

M. Taylor

2007 RENNTECH SL600 R3 Package
Posted By: RENNtech
Hi George & Team,

Just wanted to let you know the ECU arrived to my house as scheduled this morning. I installed it immediately and took the car for a drive. All I can say is, HOLY SMOKES! The car drives stock-like at partial throttle, but press the pedal to the floor and it's like an entirely different animal!

The tires even break loose when going WOT on the freeway at speed! Needless to say, I'm very impressed, and can't thank you guys enough for your great customer service and top-notch product.

I will let you guys know how the car performs at the Airstrip Attack event next month, hosted by Shift-Sector. I also plan the get the car re-dynoed later this week to see what kind of power it's now putting down.

Oh, and thank you also for throwing in the BMC air filters, that was a nice touch.
I look forward to doing more business with you in the future.

Eric F.

2012 E63 Biturbo (W212)
Posted By: RENNtech

My initial thoughts: amazing off the line torque and throttle response at all shift points...I am going to bury a lot of unnecessary miles on this beast over the weekend. Thanks for an amazing product and for you professionalism.

My best,

Adam E.

(W463) G63 AMG Biturbo
Posted By: RENNtech
Dear George,

I wanted to take the time and share my satisfaction with the results f the tuning of my 2008 CL 65. Not only did you deliver on your original prediction on HP and torque, but exceeded it by 50 on HP and 100 Lb/ft on torque. I'm now at 715 HP and 965 TQ. The end result is a huge improvement from its original base line in both power and torque.
You guys hit it out of the ball park and delivered well above your original prediction.


Manny V.

2008 CL 65 (C216)
Posted By: RENNtech
Hi George,

I have received the parts (R1 Performance Package) & tried them out- so far the results have been astounding ... With just these mods, the E63 was able to kill a G-Power supercharged M3 and almost ran level with a McLaren MP4-12C in a rolling race!




2012 Mercedes E63 Biturbo (W212)
Posted By: RENNtech

I wanted to take the time and write you about my thoughts and satisfaction on the RENNTech V3 Lowering module for my 2010 W212 E550 Sport sedan, equipped with AirMatic suspension. I work in an office environment in Orange County, CA and use this car as my daily driver to haul both my 2 year-old daughter and clients around, although not both at the same time.

I purchased the E550, which is black on black, with the idea of doing mild modifications that were both sporty and street friendly. These mods would include lowering, exhaust, ECU tuning, window tint, 19" wheels and some interior accents. My previous cars were a CLK55 AMG and BMW M3 and have had my share of potholes and rough ride quality.

When doing my research for the lowering module, I, like many others, took to the Internet. As you know, there is a lot of noise out there. I decided that if I was going to use a lowering module for my E550, I wanted to go with a reputable, Mercedes-tuner, with a quality reputation and a name for performance. This dwindled my short list to RENNtech and Brabus.

The Brabus module was fixed, meaning it did not offer any choices of custom lowering heights. I decided to call you guys and Tomas and George were extremely helpful. They always picked up the phone and were more than generous with their time answering my questions. In this day and age of call centers and poor service, these guys were 5-star and one of the reasons I felt comfortable with the unit and decided to go with RENNTech. It's everything that it's advertised to be and I am extremely happy with the results. Easy, quick install, done by the authorized RENNTech dealer HG Motorsports in La Jolla, CA. The software was easy to download on my laptop and very user-friendly. I was able to customize my 3 settings quickly. I call them Mild, Sport and Aggressive Drop. The pictures of my car are with my mild setting, which is -.75" in front and -.70" in rear.
Thanks again for producing a quality unit and for all the support and help. I'm going for the RENNtech ECU tune next!


2010 E550 (W212)
Posted By: RENNtech

<< Start Previous 1 2 3 4 5 6 7 8 9 Next Last >>

Page 6 of 9


Contact us

7825 SW Ellipse Way, Stuart, FL 34997
(+1) 561 - 845 7888
Mon - Fri 9am - 6pm


© 2017 RENNtech, Inc. All Rights Reserved.
7825 SW Ellipse Way - Stuart, FL 34997
TEL: 561.845.7888 FAX: 561.845.6777 E-MAIL: