S550 RENNtech ECU Upgrade

[JohnH4260]

Has anyone done a RENNtech ECU upgrade for the S550? It's listed on the RENNtech site (http://www.renntechmercedes.com/) for $1795. If so, are you pleased with the results?

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[trumpet1]

Originally Posted by JohnH4260

Has anyone done a RENNtech ECU upgrade for the S550? It's listed on the RENNtech site (http://www.renntechmercedes.com/) for $1795. If so, are you pleased with the results?

I wouldn't do it. You're only gaining 22hp and the HP is already darned good as is. On the other hand, I did it on my 600 and gained 100HP and gained 120 ft/lbs and noticed a major difference. If you still want to do this, talk to Adam Goodwin with Evotech. He advertises on here all the time. He'll do a great job for you.

[kenstudios]

Biggest benefit is to remove the 133 mph top speed limiter.

[Alex@wheelexperts]

i have it, it made a big difference... i really like the extra power in the mid to top end

RENNTECH is great!

[trumpet1]

Originally Posted by RESPECT

i have it, it made a big difference... i really like the extra power in the mid to top end

RENNTECH is great!

One thing I did notice was how much sooner the power and torque begins. Without Renntech, after kicking down, it seemed to me it took the surge about one second to kick in. Now it happens immediately. Just my observation.

[MJ50]

FYI - SI ECU is $500 less for pretty much gain #s...
i can vouch for SI ECU since i have it on my 203...

[TuneTime]

My friend had the RennTech Upgrade it done to his 550... and i can say the hp gains are ok... but its more the "light to light" torque that you pick up... it comes in lower in the RPM range and makes it feel alot more powerful... and yeah raises the top speed limiter for those 170+ cruises.....

[LA TECH]

Because the S550 is a normally aspirated vehicle you will not feel the horsepower or Torque gain as much as if it were a kompressor vehicle. Reason being there is no boost to turn up. However it does adjust your timing and air to fuel mixture which will definetly help. Overall I would highly recommend it, just dont expect to get a 50HP gain.

Originally Posted by JohnH4260

Has anyone done a RENNtech ECU upgrade for the S550? It's listed on the RENNtech site (http://www.renntechmercedes.com/) for $1795. If so, are you pleased with the results?

[JohnH4260]

Just received this message from RENNtech today (07 FEB 2008).

“There is a lot more power in our ECU tune than we publish, over 20 HP at the wheels and about 25 lbs of torque. This is good for about 3/10 of a second quicker 0 to 60. The only thing I have seen that is better is the ECU and headers we have on our S550, 0 to 60 in 4.8.”

If you have any questions, please call me 561-845-7888 or email Bobb@renntechmercedes.com

Bob Brady
RENNtech

[trumpet1]

Originally Posted by trumpet1

I wouldn't do it. You're only gaining 22hp and the HP is already darned good as is. On the other hand, I did it on my 600 and gained 100HP and gained 120 ft/lbs and noticed a major difference. If you still want to do this, talk to Adam Goodwin with Evotech. He advertises on here all the time. He'll do a great job for you.

Uhh, I guess based on the controversy I've been reading on other forums , it would be best to talk straight to Bob Brady at Renntech before doing this. Scratch my earlier post. I have been VERY pleased with my Renntech upgrade done by Jeff at Renntech. In fact, I have been talking with Bob lately and I plan on going to his shop for a dyno test and a tweaking while I'm there in early May. Bob, I plan on taking you out for lunch while I'm there. I really feel these guys know what they are doing.

[trumpet1]

What exactly happens to a transmission that gets fried by too much power and torque??? Are the clutches stripped? Gears stripped? Mounts broken? What exactly goes bad or is broken when a transmission fails? What is going on when a tranny is in "limp mode"?

[JohnH4260]

Originally Posted by trumpet1

What exactly happens to a transmission that gets fried by too much power and torque??? Are the clutches stripped? Gears stripped? Mounts broken? What exactly goes bad or is broken when a transmission fails? What is going on when a tranny is in "limp mode"?

With modern cars, engine management is controlled by the ECU (electronic control unit) and other computers. The computers control ignition, fuel injection, transmission, brake system, etc., and can make significant changes to the way a car operates.

As with all things electronic (or mechanical), things can go wrong. Computers crash. Software can become corrupted or may require an update. As a result, ECU's are fitted with "limp home mode". If an electronic or mechanical problem arises, the ECU enters "limp home mode", which limits the engine revs beyond a certain RPM limit, won't allow fast acceleration, or may limit the maximum speed to 40 mph (or so).

Bad? Not really. The alternative would be operating the vehicle at regular speeds, with the danger of damaging the car or inconveniently having the vehicle shut down completely.

[V12AMG]

Do you have to advise your dealer not to reflash when you go in for service? I know my dealer will automatically apply new ECU firmware if/when it becomes available, even if I go in for an oil change. It doesn't happen often, but it does happen. I'm assuming if they did do a flash upgrade, it would overwrite the Renntech code?

[trumpet1]

Good question because after my service B, I noticed on the invoice that the ECU software was flashed (or some wording of that effect). However, I still feel that my Renntech upgrade is in effect because the engine still has that extra punch that I don't recall having prior to the upgrade.
I'm hoping to go down and see Bob Brady in early May to have it all tweaked and dyno'd. My MB techs know by looking at the Renntech badging that I had this done and hopefully the tech had enough sense to not mess with it. They came out and asked me how it was performing and I said it was awesome power.
The Renntech upgrade for my S600 gave my car extreme torque and speed. It is downright frightening sometimes. Just yesterday I pressed down on the pedal while at 60 mph and I believe I hit 110 mph in less than 4 seconds.

[kafklatsch]

What is the top speed and 0-60 estimates with a Renntech ECU for the s550? I cant find anything on the net.

Originally Posted by JohnH4260

Has anyone done a RENNtech ECU upgrade for the S550? It's listed on the RENNtech site (http://www.renntechmercedes.com/) for $1795. If so, are you pleased with the results?

[kafklatsch]

bump

Originally Posted by kafklatsch

What is the top speed and 0-60 estimates with a Renntech ECU for the s550? I cant find anything on the net.

[kafklatsch]

come on guys....... i give up whats the answer

Originally Posted by kafklatsch

bump

Originally Posted by kafklatsch

What is the top speed and 0-60 estimates with a Renntech ECU for the s550? I cant find anything on the net.

[kafklatsch]

Originally Posted by kenstudios

Biggest benefit is to remove the 133 mph top speed limiter.

have you checked the top speed? ..... or how fast have you gone?. the 133mph is a near deal breaker..... when I bought my s55 I was doing better financially.... now I am looking at an s550..... I am really sick over the 133 limiter after having the limiter on my s55 removed and i have seen 177 on the odometer.... I hit 140+mph every now and then.... it gets there so quickly.

On another note, the rear seat package and rear a/c get ooohhhs and ahhhhs from my passengers.... that too is a desired option for me. That option really matches the price and luxury of the car.... so i am weighing money versus options.... very confused at the moment due to being a bit poorer in the obama age.

[jta00r1]

Originally Posted by kafklatsch

have you checked the top speed? ..... or how fast have you gone?. the 133mph is a near deal breaker..... when I bought my s55 I was doing better financially.... now I am looking at an s550..... I am really sick over the 133 limiter after having the limiter on my s55 removed and i have seen 177 on the odometer.... I hit 140+mph every now and then.... it gets there so quickly.

On another note, the rear seat package and rear a/c get ooohhhs and ahhhhs from my passengers.... that too is a desired option for me. That option really matches the price and luxury of the car.... so i am weighing money versus options.... very confused at the moment due to being a bit poorer in the obama age.

so you got poorer in a matter of months? hmmm.

[kafklatsch]

Originally Posted by jta00r1

so you got poorer in a matter of months? hmmm.

YEP...... but if you require clarification....... I am poorer now than i was in 2008, and 2006 and 7........... thus the s550 (which looks much much better than my 55 anyway) questions.... it may have a little to do with the current economy..... and there are all kinds of discussions this could lead to..... I will leave the assumptions for those personality types to ponder, but i will revert back to my initial question....

what is the top speed of a renntech chipped s550?

[CL55_Serge]

You know, given the trend, in the next few months you may be asking the following question, "What is the top speed of a Renntech-chipped C350?"...

Just kidding! I would imagine a non-limited S550 should be in the 170+ range. Is that fast enough for you? My CL55 is chipped, but I never pushed it past 140 I don't think... Debating whether to do my S550...

You can also take a look at this company for ECU re-programming, would save you a few bucks if you all you care about is the limiter to be removed:

http://www.singhautosport.com/

Originally Posted by kafklatsch

YEP...... but if you require clarification....... I am poorer now than i was in 2008, and 2006 and 7........... thus the s550 (which looks much much better than my 55 anyway) questions.... it may have a little to do with the current economy..... and there are all kinds of discussions this could lead to..... I will leave the assumptions for those personality types to ponder, but i will revert back to my initial question....

what is the top speed of a renntech chipped s550?

[jbondox]

All those companies out there working on MB's now... it is like going to see a dentist for a kidney stone... stick with the companies that are an authority of MB, By far Renntech and Brabus have the vehicle dialed in, Kleeman also, but the first person I am calling is Renntech for any mods.

you'll feel the 20hp gain with the ECU tune, hell the Brabus ECU tune is 5x as much and the same gains

[CL55_Serge]

I hear you, but why? Aren't these 2-tier companies just reverse engineering the Brabus or Renntech programs and making the same settings? You think there are actual differences in programs? Would love to get to the bottom of this...

Originally Posted by jbondox

All those companies out there working on MB's now... it is like going to see a dentist for a kidney stone... stick with the companies that are an authority of MB, By far Renntech and Brabus have the vehicle dialed in, Kleeman also, but the first person I am calling is Renntech for any mods.

you'll feel the 20hp gain with the ECU tune, hell the Brabus ECU tune is 5x as much and the same gains

[jbondox]

brabus and renntech are professionals and have resources with MB, the other fly by nights... I can not see their relationship. afterall mb did give a glk to both companies for design... which renntech ultimately won.

[CL55_Serge]

That's fair, the big tuners are more reputable and stand by their work. My take is that these smaller shops simply reverse engineer and you end up getting the same settings flashed to your car - but at a much lower price point.

I might go low end and then have a friend with a Star Diagnostics system take a look at the settings. We'll do the same thing on a Renntech or another tuner's settings and do a comparison: which changes were done/not done, what the settings where - etc.

From what I understand so far - fuel map changes, the pedal/potentiometer ratio or when it engages changes to make the car feel quicker (makes gas pedal more sensitive), shift points, timing. Anything else?

Would someone with a decent dyno be able to tune the car with similar results?

If anyone knows the technical side of this, would be good. I completely agree that Brabus, Kleemann, Renntech have the R&D capabilities and come out with quality products. But this isn't rocket science - folks should be able to come to similar conclusions with the right tools with a dyno.

Originally Posted by jbondox

brabus and renntech are professionals and have resources with MB, the other fly by nights... I can not see their relationship. afterall mb did give a glk to both companies for design... which renntech ultimately won.