SL/R230: Spent $6,400 w/Renntech for Upgrade - BYE BYE RENNTECH!
MBWorld Fanatic!




Joined: Sep 2006
Posts: 1,921
Likes: 173
From: Long Island New York
2003 SL55,2020 GTC ,2017 GTS sold ,2002 G500 Sold,2003 SL500 Sold,
Renntech
Call the credit card company and dispute the charge,they immediately take the charge off and get both sides of the story,Ive done it a two times,just dot your I's and cross the T's ,be professsional and dont lose your cool, I found it a little frustrating because the people you are going to be explaining you side too are not MB Techs so I had to explain my side in simple terms,My dealings were with some high perf snowmobile engine parts ,I had my own Land and Sea dyno so I could show the lack of power promised as opposed to their advertised claim,one refund of $1000.00 was granted one for $700.00 was not, I say go for it,good luck,
I have a Kleeman Supercharger on my 03 SL500,wasnt performing the same after a few 1/4 mile passes,Cory at Kleeman told me to disconnect batteries for ten minutes and try it again,picked up tenth and a half and 3 mph,what did that do,I have no idea but it made car faster ,these cars are finicky with alot of electronics and computer stuff going on,no more setting the timing and putting bigger jets in the carb
,maybe they can fix it for you , DONT THROW THAT KIND OF MONEY AWAY
I have a Kleeman Supercharger on my 03 SL500,wasnt performing the same after a few 1/4 mile passes,Cory at Kleeman told me to disconnect batteries for ten minutes and try it again,picked up tenth and a half and 3 mph,what did that do,I have no idea but it made car faster ,these cars are finicky with alot of electronics and computer stuff going on,no more setting the timing and putting bigger jets in the carb
,maybe they can fix it for you , DONT THROW THAT KIND OF MONEY AWAY
Yes, I thought I would add it.
It is being custom made and will be ready the beginning of July. It should be a blast.
I have used Renntech on my S600 and my SL65 and they both worked out quite well.
I dealt directly with Renntech and did the swap myself, I didn't dyno the cars before and after but the difference in power was instantly noticable.
Before ordering the upgrade Renntech told me that the upgrade was refundable if I wasn't happy with no questions asked. So I am sure you can get your money back if the computers are taken back to factory programming. To not ask for a refund would be quite foolish in my opinion.
I dealt directly with Renntech and did the swap myself, I didn't dyno the cars before and after but the difference in power was instantly noticable.
Before ordering the upgrade Renntech told me that the upgrade was refundable if I wasn't happy with no questions asked. So I am sure you can get your money back if the computers are taken back to factory programming. To not ask for a refund would be quite foolish in my opinion.
All my MBworld clients that purchased 600/65 software from Renntech are generally happy clients. EuroElites will always try to work things out for both Renntech and the clients. I am sure Renntech will do the same.
MBWorld Fanatic!
Joined: Feb 2002
Posts: 6,061
Likes: 326
From: 2000 ft over the FL coast in a B-17
Various
I have personally dealt with Harmut quite a few times and he has always been a stand up guy; he even helped to solve a warranty problem MB could not figure out with my E55 by calling his friends at AMG Germany. I'm not implying you did anything wrong, but I would like to hear Harmut's side of things.
I have not been around here for a while and just read this post, I too have the same problem with my Sl 600, while it is fast as hell and and I love it, it never produced the #'s they claimed I would see and was also told that it was a bad intercooler but after 2 day's of testing at the local MB dealer, nothing was found to be wrong.
I have not taken it to Renntech and it did not bother me that bad because I have not come across anything that has kicked my behind on the roads here locally yet. lol
I also feel that the #'s on the dyno should atleast be close to what Renntech advertised them to be, bu they fell short.
I have not taken it to Renntech and it did not bother me that bad because I have not come across anything that has kicked my behind on the roads here locally yet. lol
I also feel that the #'s on the dyno should atleast be close to what Renntech advertised them to be, bu they fell short.
Senior Member
Joined: Oct 2006
Posts: 290
Likes: 16
2018 Mercedes E63 S, Boring SUV, 2015 CLS63 AMR Stage 1 (traded), 2015 Audi S8 w/ APR stage 2 (sold)
My CL600 after the Renntech upgrade was a night and day difference. My car is about dead even with C6 Z06 and the Ford GT. I recently beat an '03 Murcielago, so I think my car with the upgrade is running great.
I have not been around here for a while and just read this post, I too have the same problem with my Sl 600, while it is fast as hell and and I love it, it never produced the #'s they claimed I would see and was also told that it was a bad intercooler but after 2 day's of testing at the local MB dealer, nothing was found to be wrong.
I have not taken it to Renntech and it did not bother me that bad because I have not come across anything that has kicked my behind on the roads here locally yet. lol
I also feel that the #'s on the dyno should atleast be close to what Renntech advertised them to be, bu they fell short.
I have not taken it to Renntech and it did not bother me that bad because I have not come across anything that has kicked my behind on the roads here locally yet. lol
I also feel that the #'s on the dyno should atleast be close to what Renntech advertised them to be, bu they fell short.

When you say they fell short of their published numbers, you do realize that the numbers they publish are at the flywheel and not at the rear wheels right? What did you car dyno at? Did you dyno it before the upgrade? What percentage of loss did you use to compute the flywheel horsepower?
I do not have the #'s and it has been a while so I do not want to make up a #, I do remember it was short and when I call Renntech the guy over thee on the east coast of Fl told me I must have a bad itercooler, so after the MB dealer found nothing wrong with mine I give up on the whole thing and just enjoyed all the power it does have.
After my original post, I got an e mail from Bob Brady asking the same things and were I had the Dyno done, i replied and also asked where he recomends I take the car to have it dyno and go from there, but never heard back from him or anyone else at Renntech.
Oh well, I have a few Benz now and at age 34 I am sure I will buy many more before I drop dead and if that is there attitude I say screww them!!!
I do not have the #'s and it has been a while so I do not want to make up a #, I do remember it was short and when I call Renntech the guy over thee on the east coast of Fl told me I must have a bad itercooler, so after the MB dealer found nothing wrong with mine I give up on the whole thing and just enjoyed all the power it does have.
After my original post, I got an e mail from Bob Brady asking the same things and were I had the Dyno done, i replied and also asked where he recomends I take the car to have it dyno and go from there, but never heard back from him or anyone else at Renntech.
Oh well, I have a few Benz now and at age 34 I am sure I will buy many more before I drop dead and if that is there attitude I say screww them!!!

After my original post, I got an e mail from Bob Brady asking the same things and were I had the Dyno done, i replied and also asked where he recomends I take the car to have it dyno and go from there, but never heard back from him or anyone else at Renntech.
Oh well, I have a few Benz now and at age 34 I am sure I will buy many more before I drop dead and if that is there attitude I say screww them!!!

Renntech offers quality products but if you deemed that their customer service is way below par, then you can purchase Renntech products from dealers and have the dealers to deal with Renntech. I deal with Renntech daily, regardless of their busy timetable. In my book, customers come first, and certain individuals at Renntech might not believe in that
, doesnt mean that all Renntech dealers should be the same way. So guys, if you have questions regarding Renntech products, PLEASE contact me first if you do not want to deal with Renntech's customer service.
To ENERGY341o8
I do not have the #'s and it has been a while so I do not want to make up a #, I do remember it was short and when I call Renntech the guy over thee on the east coast of Fl told me I must have a bad itercooler, so after the MB dealer found nothing wrong with mine I give up on the whole thing and just enjoyed all the power it does have.
After my original post, I got an e mail from Bob Brady asking the same things and were I had the Dyno done, i replied and also asked where he recomends I take the car to have it dyno and go from there, but never heard back from him or anyone else at Renntech.
Oh well, I have a few Benz now and at age 34 I am sure I will buy many more before I drop dead and if that is there attitude I say screww them!!!
Sorry you did not hear from me but I never recieved your Email. It might be just as easy to give me a call.
Bob Brady 561-845-7888 @ RENNtech
After my original post, I got an e mail from Bob Brady asking the same things and were I had the Dyno done, i replied and also asked where he recomends I take the car to have it dyno and go from there, but never heard back from him or anyone else at Renntech.
Oh well, I have a few Benz now and at age 34 I am sure I will buy many more before I drop dead and if that is there attitude I say screww them!!!
Sorry you did not hear from me but I never recieved your Email. It might be just as easy to give me a call.
Bob Brady 561-845-7888 @ RENNtech
Super Member
Joined: Dec 2002
Posts: 911
Likes: 1
From: Wichita
2005 SL600, 2011 Honda Odyssey Touring Elite
While we have you here, can you clarify this intercooler issue? Is the stock intercooler in the SL600 defective? Can you get specified performance from the Renntech upgrade without changing out the stock intercooler or is it just that upgrading the intercooler improves the performance even further?
Bigbob,
While we have you here, can you clarify this intercooler issue? Is the stock intercooler in the SL600 defective? Can you get specified performance from the Renntech upgrade without changing out the stock intercooler or is it just that upgrading the intercooler improves the performance even further?
While we have you here, can you clarify this intercooler issue? Is the stock intercooler in the SL600 defective? Can you get specified performance from the Renntech upgrade without changing out the stock intercooler or is it just that upgrading the intercooler improves the performance even further?
The cooling upgrade doesn't increase boost further but upgrading the intercooler pump improves and sustain the power band longer while @ full load. Hope this helps.
Last edited by AdamG@NorCal; May 17, 2007 at 08:22 PM.
Super Member
Joined: Dec 2002
Posts: 911
Likes: 1
From: Wichita
2005 SL600, 2011 Honda Odyssey Touring Elite
Sorry you did not hear from me but I never recieved your Email. It might be just as easy to give me a call.
Bob Brady 561-845-7888 @ RENNtech[/QUOTE]
Sorry I felt you were blowing me off, I will call you and hopefully we can resolve this issue.
Thank you
Bob Brady 561-845-7888 @ RENNtech[/QUOTE]
Sorry I felt you were blowing me off, I will call you and hopefully we can resolve this issue.
Thank you
Sorry if I couldnt be of any help.
Here is Renntech's press release on the Intercooler upgrade mod.
Intercooler upgrade
Currently the 55 Kompressor engines and the V12 twin turbo MB cars have two cooling systems, a high temperature system for the engine and a low temperature system for the intercooler, these are separate systems only sharing expansion reservoir and over flow.
The current intercooler water pump has had some problems with durability, some individuals have tried pumps that are slightly better and have a greater flow, but these pumps are not designed to give the higher pressure that is required to work efficiently.
Our intercooler upgrade includes a heavy duty water pump developed for racing. This pump not only provides the flow but also the pressure that is necessary to circulate the coolant to cool down the intake air.
Our kit also includes an additional radiator portion for the intercooler.
With this kit we are seeing a 20 to 30 degree Celsius drop in intake air temperature.
---------------------------------------------------------------------
I am sure Bob will reply tomorrow am if you need further info.
Here is Renntech's press release on the Intercooler upgrade mod.
Intercooler upgrade
Currently the 55 Kompressor engines and the V12 twin turbo MB cars have two cooling systems, a high temperature system for the engine and a low temperature system for the intercooler, these are separate systems only sharing expansion reservoir and over flow.
The current intercooler water pump has had some problems with durability, some individuals have tried pumps that are slightly better and have a greater flow, but these pumps are not designed to give the higher pressure that is required to work efficiently.
Our intercooler upgrade includes a heavy duty water pump developed for racing. This pump not only provides the flow but also the pressure that is necessary to circulate the coolant to cool down the intake air.
Our kit also includes an additional radiator portion for the intercooler.
With this kit we are seeing a 20 to 30 degree Celsius drop in intake air temperature.
---------------------------------------------------------------------
I am sure Bob will reply tomorrow am if you need further info.
Last edited by AdamG@NorCal; May 17, 2007 at 10:06 PM.
Super Member
Joined: Dec 2002
Posts: 911
Likes: 1
From: Wichita
2005 SL600, 2011 Honda Odyssey Touring Elite
It's just that when two members, StephenK and Energy34108, had complained to Renntech that they were were not getting the performance they were expecting, they were told that it was because of a faulty stock intercooler. Nowhere in the Renntech literature does it state that you need an upgraded intercooler in order to achieve the claimed horsepower rating. No asterisk about some cars having faulty intercoolers, nothing... just 625 HP, 745 TQ.
Look, I'm not opposed to people making a buck selling upgrades, nor am I taking the side of StephenK and Energy34108, I just want to get to the bottom of this.
Look, I'm not opposed to people making a buck selling upgrades, nor am I taking the side of StephenK and Energy34108, I just want to get to the bottom of this.
RENNtech
I looks as if Adam has answered your question regarding the Intercooler pump.
As too the individuals that say they do not think they have the HP, I have yet to look at any dyno sheets that would indicate this to me. Especially since a post that I noticed quite awhile ago had claimed a 11.9 in the 1/4, which would indicate the power was there.
Since they are both in Florida, they are welcome to bring there cars to us so that we can see if there is any problem.
Currently we have Stephens ECU and are checking the programming, it is possible that MB had reset it to stock so we are redoing it. If this does not fix the problem than we will need to have the car at our Florida location to see what the problem is.
The power we look for on our dyno at the wheels for the 600 is in the area of 500 HP and 596 Tq. This dependent on fuel quality and temperature.
Our V12 modification have been our most popular here and in Europe.
I hope I have answered your questions.
As too the individuals that say they do not think they have the HP, I have yet to look at any dyno sheets that would indicate this to me. Especially since a post that I noticed quite awhile ago had claimed a 11.9 in the 1/4, which would indicate the power was there.
Since they are both in Florida, they are welcome to bring there cars to us so that we can see if there is any problem.
Currently we have Stephens ECU and are checking the programming, it is possible that MB had reset it to stock so we are redoing it. If this does not fix the problem than we will need to have the car at our Florida location to see what the problem is.
The power we look for on our dyno at the wheels for the 600 is in the area of 500 HP and 596 Tq. This dependent on fuel quality and temperature.
Our V12 modification have been our most popular here and in Europe.
I hope I have answered your questions.
Super Member
Joined: Dec 2002
Posts: 911
Likes: 1
From: Wichita
2005 SL600, 2011 Honda Odyssey Touring Elite
And thank you for stating what the dyno reading should be after the upgrade. What is the ideal fuel and temperature for the test?







