Hey folks. I’m back after cheating on the brand for a while. After a nasty divorce I gave up the 550, went with a Volvo S90 T8 then bought a GL 550 to haul the kids. Then got rid of the Volvo got a Lexus LC 500. While I love the LC, there are a lot of things it just doesn’t have. I love that it’s ridiculously loud and looks like a hot wheels car. But outside of that it’s pretty boring. Lexus is conservative when it comes to tech. Hence the reliability. I digress…

Coming back to my beloved S550 Coupe. This time, I’m doing the same 22 inch wheels, same color fully loaded this time with night vision and magic sky. I’m doing the grille swap to a panamericana. And lastly I’m really debating a stage 1 “intermediate” renntech tune.

I decided if I’m going to go with the tune I would do their intermediate stage 1. I’m not into, nor do I want to deal with other mods. But I’m wondering…

1. Are the gains worth the cost? Please don’t try to talk me into cats, headers or anything else. Not happening.
2. Is the difference really that noticeable?
3. Is a TCU recommended? Or is it conservative enough that the TCU tune isn’t necessary?
4. Should I be worried about added stress on other components? This is my daily driver I don’t want headaches.

Any guidance would be appreciated. I know OKBarnett is around here somewhere!

 

No one?

 

Not sure if this is considered the stage 1 intermediate, but I have the higher rated (540hp) Renntech hand held tuner. I love it. I as well as my 15 year old son can feel the difference. Even my wife says it was faster. I've "surprised" quite a few performance cars as well as a BMW 1000rr sportbike. I've done the panamericana grill swap. Getting it wrapped now in Satin Black and just got my wheels Silver Vossen HF4t powdered coated to gloss black. had 22s but the potholes in DC made me change my mind. went with 20s

Had a guy driving an Audi rs4 follow me off the highway exit to see what i was driving. He was behind me on the highway and said he heard nothing until I stepped on it, so I assume it sounds good. lol

 

Thanks for that @ dcbb. It sounds like you went to the “stage 2” @540hp. I went with the more conservative tune at 500hp because I wasn’t looking for added strain on parts. It sounds like you’ve been having a blast with your stage 2. Speaking of surprising people, I have a GL 550 that keeps up with the best of them people are always surprised that some big kid hauling SUV is bustin’ their ***.

I’m probably going to regret not going with the 540hp version now.

With respect to your wheels, I had 22s on my 2015. I’m actually getting another 550 with the exact same setup same color, except the interior color is different. I too live in the DC metro area but never had an issue. I run Continental DWS06 with a 295/25/22 and 255/30/22. Never had an issue. The wheels are RoadForce. I used to spend thousands on fancy wheels like Forgiato 3 piece wheels etc. They all damaged way too easy. These suckers are solid.

It sounds like you’re saying the tune improved your exhaust notes too?

 

I didnt do any tune to my car. But I would only do the renntech, and check their site to find out if you probably need the diverter valve. the 4.7 is the same engine as the 5.5 except, the 5.5 is tuned up bigger, bigger turbos.

 

Everyone tells me it sounds different. I can't really hear because I'm always behind the wheel. lol. I had 22 inch Rennen rims fronts 265/30-22 , rears 315/25-22

22 inch Rennen CSL-4 265/30r22 315/25r22

20 inch Vossen HF-4T 255/40r20 285/35r20

 

@dcbb The 22s are the way to go. I like the first set of wheels a lot.

 

I have the Weistec Tune (540hp/715tq). Let me be very honest with you.

The difference you feel is above 2000+ RPM. At that range it pulls much harder. But if you pay attention, in normal driving, you usually don’t get up there. So I wouldn’t say there’s much difference in day-to-day driving, only when you stomp on it. I would assume the Renntech is the same, but can’t say for sure.

 

@cfmistry thanks for the feedback. Another 540hp tune. Ugh, I went with the 500. Regretting it already. Thanks.

 

If it makes you feel any better, I probably wouldn’t do it again. I basically spent $1800 on something I never use.

 

I think the 550 power is ok. Its the soft suspension I dont like. I finally traded up to a S63 and the whole car is a different animal. First, the trans is totally different. A double clutch. It shifts better and has different modes. the engine is definitely more powerful. You feel the 100 extra hp. And the suspension its totally a stiff amg ride. I love it.

 

@cfmistry That does not at all make me feel better spending $2500 on 500HP tune from Renntech. 😂 But I appreciate the effort.

@okbarnett Can I go on record to say I hate you? I had an LC 500 that God forbid you floor it on the highway it sounded like the tranny was going to drop out. It slams into whatever get it could find. Going back to a C217 or Mercedes in general reminds me why I keep coming back. You can't beat a high-end Benz period. Listen man, I don't have S63 money at this time. I cap out at $70K for a car. Anything over, I'm not there yet. 😂. My next plot is the AMG 4 door. I need a couple more years.

 

I really like those RF wheels on your car. A lot. Wish they made them in 20”s, I don’t think I’d tolerate the bumpiness of 22”s.

 

@cfmistry They make them in 20". https://audiocityusa.com/shop/20-Sta...ined-Rims.html

I would suggest purchasing them from Aspire Motoring (they were top notch dealing with them). https://www.aspiremotoring.com/

 

OK well $2500 later I bought the Renntech stage 1 (intermediate tune). I used the hand held tuner (hht) it took 2 mins.

The car was already fast but I must say the tune took it up a notch. It's pretty conservative. I wish I did the stage 2. But I must say there is a lot of pep in the step now. I would say "E" mode feels like "S" mode. And "S" mode feels like sport plus. I'm not sure it's worth $2500 if I'm being honest. $1K yes. $2, 500 I'm not sure its worth that.

My wife was surprised I tuned it so quickly. She thought we had an appointment. 😂

She was like "wait that's it?" Yes baby. That's it. "Can I do that to my VW too?" "Yes baby but it won't be Renntech with your 1.4 l turbo."

I went with Renntech for the name/brand I had a local AMG tuner that would have done it for $995. If I had to do it over u would have likely taken it to the local tuner.

 

I am not a s class owner , beautiful car by the way . i have a E550 i purchased the Renntech ECU tune and the V3 lowering module . and wow the difference i have the M278 4.7l bi turbo. . stock at 402hp to 540hp

 

@M_patton Thanks can I ask you a couple of questions...

1. How long have you had the tune?
2. Do you get on the throttle?
3. Did you need to change other parts to keep up with the power? Is anything wearing out faster.

I definitely feel the difference with the 500hp 625lb ft of torque intermediate tune. So much so that I want to tune my GL 550 too. I was just concerned with wear and tear.

The intermediate tune is definitely a nice way to kick it up a notch. Even stock I think it could beat my Lexus LC 500. With the tune it can definitely beat it but your tune is what puts the engine in another class.

​​​​​I might inquire with Renntech if I can exchange the tune for the next level and pay the difference. I'm guessing no, but you won't know if you don't ask. Particularly if I mention I will order a tune for the GL 550 too.

 

1---I Actually purchased this car with the tune and the v3 lowering module however i had a same year e550 That got totaled in an accident . 402 hp is all-ready a-lot in my opinion . but the tune on this car its really fast ..
i have had the car for 8-9 months . i have had to replace the intake hoses only because they got brittle. I knew the owner and as far as i know he replaced spark plugs . because it was recommended from RENNtech

2- I would like to say i do not get on the throttle but, LOL . I am not heavy footed so no i do not dog it or anything ...It is a really nice car to cruise in too.

3. Not that i know of But its interesting you ask that cause i have been looking into that as well .. i am positive i will not be looking for anymore more horsepower or modifying it anymore than it is .. its way fast enough I have often wondered about a BOV valve just to prolong turbo life .. maybe some upgraded pulleys stuff like that. i surely want to keep it like it is . I really like this car.

 

Ok
I talked extensively with renntech
they say no
there is nothing more needed to do

 

Thanks for the feedback, I appreciate it.

 

After talking to Renntech. That day .
i specifically asked the guy ..
is there anything you recommend I do to the car as far as upgrades
without doing a retune .

He recommended the renntech BOV
and the Renntech intercooler pump upgrade . So I will prolly do both of those in about 2-3 months .
i am going to put that weistec oil filter cap on it as well .

i would think the BOV would help the Turbos longevity
and I live in very hot climate so I think
the intercooler pump is a great upgrade .

now that you have had it a little bit how do you like your tune ?

 

Sorry it took so long to respond. Man, the Renntech tune is a BEAST!!! The car transformed into a monster. It wants to go at all times. Sport mode really turns it into a monster. I'm in loooooove with the power and the Renntech tune! Highly recommend if you want to really unlock the beast.

I was so impressed I went to tune my GL 550. But I cheaped out and found a tuner online. I couldn't see dropping another $2500 on a tune for my kid hauler. I guess you get what you pay for. The tune sucked on the GL 550. It made my tranny shift hard, it ran rougher and I can't tell if it gained any power. Whereas the Renntech S coupe tune was night and day. It literally turned into another car. I don't think I would use any other tune other than Renntech moving forward.

Also swapped the grille on the S Coupe to panamericana. And swapped the grille on the GL 550




**UPDATE** Purchased the blacked out MB illuminated emblem as well. Resprayed the mesh pieces to black again as they were fading.

 

I have 540hp renntech on my 550. For sure it cost their money.