I'm getting ready to purchase my first MB and have had a hard time deciding if I wanted a 600, or if I wanted to fork up the extra money for a 65. I decided on the 65 and have been in negotiations with a local dealer on an '06 with about 30k miles. We're agreed on price but there's one major hick-up.....the car seems to be underpowered.

I drove the car for the first time a few days ago with the salesman and my brother (who owns a stock S600) in the back seat. After a few short blasts I turned to my brother in the back seat and said "this things a turd"- to which he and the salesman fully agreed. It felt significantly slower than my brothers 600....it wouldn't even break the tires loose from a dead stop.

After suggesting to the dealer that maybe the intercooler pump was bad and other various possibilites they told me that they had just replaced the pump and assured me that was not the problem.....and that the "computer had been completely reset during the install and the car needs to re-learn the driving habits of the driver"...they assured me that over time the performance would improve. My brother and I both agreed that car needed about 100-130hp to make it right. I left empty handed and told them to call me when they found out what was wrong.

The salesman calls me 24hrs later and tells me he drove the car all day and it's "much better....night and day difference"....and that they changed nothing, just drove it. So, this morning I went for another test drive and indeed it WAS much better.....I'd say a 50-60% improvement since the day prior. So, just to be sure, my brother and I lined up his stock 600 next to me in the 65 (with the salesman riding shotgun with me) on a feeder road and got after it.....my brother pulled me both times. Not real bad, but he was definitely walking off on me. Once was from a 20-25mph punch and the other was 40-45- on both occassions I got my a** handed to me . The salesman was just as surprised.

We returned to the dealership and the head-tech says it's a combination of 2 things........low octane/bad gas (the car has been for sale for about 75 days and came from California where octane is as low as 85) and the ECU hasn't fully "re-learned" or adjusted for the drivers habits yet.

So, my questions are;

a) In a real world race (no magazine articles, etc) how bad should a stock '06 65 walk off on a stock '04 600....all else being equal.

b) Is it possible that bad gas (or low octane) and a computer that's been "reflashed" or "reset" would cause such a loss of power? Originally, I didn't think so- but after driving the car 24hrs later it DID improve substantially....I was very surprised.

c) If I drive the car aggressively will it slowly improve over time??


I guess what I'm worried about is going back next week, racing my brother and staying side-by-side with him? If that's the case, I'll buy a 600. The sole reason I'm looking at the 65 is becuase I want to be the fasted sedan on the road. I was always under the impression that the 65 would be .04-.05 faster than the 600 on the strip and would have no problem walking off on one from a roll. Am I wrong??

Thanks in advance for any feedback.....

-Busa196-

 

If anything, 600s are nominally underpowered. I would guess wheel horsepower rating in the real world for the two is far less than what is on paper. As well, the S65 you drove was saddled with an extra person, which I would assume is at least 150 pounds or as much as 220.

 

I think the bad gas can be a valid point. The point about the weight of the salesman is also true. The S65 is already giving away about a 200lbs weight advantage to the S600 without the passenger weight. A tuned S65 will beat a tuned S600 by about .3-.5 sec in the 1/4 mile...not sure stock to stock. I am not sure I would buy that particular car without having it be 100% first. It should be faster than the S600 from a roll even with the added weight so maybe the ECU is still adapting....unless your bro is not telling you everything about his S600...

Tom

 

Let's take a look at the power ratings:

S600 = 493hp and 590 lbs/ft torque
S65 = 604hp and 738 lbs/ft torque

S65 has 107 more hp and 148 more lbs/ft of torque.

Seems to me there should be no contest...S65 hands down.

 

I think in reality the 600's are making much more hp than they are rated at. I think the real world difference is closer to 50-60hp.

Tom

 

i agree the 600's are under rated for hp. i've messed around with a few stock s65's and have no problem keeping up with them....although i haven't dyno'd my 600, i'm guessing it's putting out closer to 550...

also, imho, a well tuned 600 V12 TT is probably one of the smoothest running beasts on the road.....

 

Why not consider an 07 S 600. Way better car all round vs the older models... More money but more car...

 

If you have an iPhone the Dynolicius app will calculate your car's 0 - 60 , 1/4 mile time and peak horsepower. It uses the GPS and accelerometer in the iPhone.. Seems like a cheap way to dyno your S600. Here is a Garage 419 review..

http://www.garage419.com/episode/419_20080807

 

We just traded my dad's S600 in for an S65 (both are W221) an I can assure you that the S65 regardless of weight differences will absolutely kill the S600 (wether tuned or not). Sounds to me as if there is something seriously wrong with the S65 you test drove. Check the turbos, TPIC, ECU and all other possibilities or just look elsewhere.

 

We (the 65) had 1/2 tank of fuel- my brother had just topped off and he probably had about 150lbs of "junk in his trunk"....golf clubs, computers, his mother-in-law , etc. so weight was as equal as it could be.


Yeah, I keep waiting for that sum ***** to tell me he RennTeched his car and didn't tell me Nah, only kidding.....he's as curious as me as to the outcome.....he was planning on a 65 (W221) for his next car.....who knows now??


My thoughts exactly. That's why I opted to spend the extra 12k on the AMG car. Up to this point those numbers prove to be bogus, but we won't know for sure until we get some good gas in the car. I hope you/me are right


I love the way the 220 looks, it's lighter than the 221, I don't want to spend an additional 30k and would like to stay married.


Great idea, but I have a problem letting an I-phone tell me what kind of power my Benz makes. That's best left to dynos and the track, IMO. In a perfect world I'd love to put the 2 on a dyno, but I'd say we're pushing our luck as it is with the NHRA "Must Qualify to Buy" program. There's definitely an advantage to knowing your salesman and having a brother with a 600


Well, that's what we tought too. The head tech has checked all the possibilities and says there's nothing wrong with the car- no codes at all. I think we're going to see a perfectly running S65 tomorrow with some good gas in it- then we'll know for sure. I can't justify the additional 12k I'm paying (vs. a 600) for the brakes, seats, dash cluster & quad pipes. If I don't walk off on him I'm back to looking for a clean 600.

 

Drive the 65 around a bit and then see how it responds...These cars don't like to sit.

 

I'm starting to look at 05/06 S65's and CL65's, and intended a drive to Chicago this weekend to drive examples. Any chance this one may be there?If this one doesn't improve, I would hate to come in behind you. Thanks.

 

Update

My brother (“housclass” on this forum) and I had a chance to go back to the dealership yesterday and drive the 65 with some fresh gas. I actually let the salesman drive it while my brother and I were in the 600- I wanted no excuses if the 600 walked off on the 65 again.

After 3 blasts down the feeder road from a 25mph punch, the 65 walked away every time- but, it was by no means a “slaughter”. I’d say by the time we were at 120ish (no worries folks, private MB test facility)the 65 was 1.5 cars ahead?? Maybe my brother will chime in. This was the 3rd time we had test driven the car and it got noticeably faster each time. I’m now the proud owner of an ’06, CPO'd, Flint Gray S65 that gets a 9 of 10 in it's overall condition. After the 40 mile drive home and some short romp sessions I swear the car felt better by the time I got home. I have no doubt that after a week or two of me piloting her, she’ll be 100%.

What I’ve learned from this;

-What they say about the computer having to “learn” the habits of the driver are absolutely, positively true. I believe you have to drive it like you stole it if you want the car to perform like it’s supposed to.

-My brothers S600 friggin flies- for the very reason mentioned above. He drives his car hard everyday and I think that’s conducive to the way it performs. I’ll bet 600 for 600 his car would have a fairly significant advantage over the average grocery getter- and even a conservatively driven 65 as we’ve demonstrated.


Special thanks to my bro for showing me the ropes and guiding me to the world’s finest luxury sedan, IMO- and for making the continued trips to the dealership to act as a test dummy. Without him, his car, and a willing sales person to act as John Force this sale would not have happened.

I’ll post some pics later. Many thanks to all of you that chimed in.

-Busa196-

 

I don't know whether the s65 has a C vs S mode, but if it does, make sure you're in S, which gives 1st gear off the line

 

busa196

Congratulations!!! I am glad the S65 was able to work out whatever problems it was having with the bad gas. Flint gray is a beautiful color. Good luck with it...and you MUST to post pictures!!!

Tom

 

You should do a search on sneaky ECU reset. This will help the car relearn the new driving habits. Many on the E55 forums have done this and swear by it. Enjoy the car and btw flint grey is best color for this car IMHO.

 

Congrats to my brother. I'm five years older than him and feel like we have taken the same paths when it comes to hot rods! i started with a 84 grand national and after 20 cars i'm working on my 4th benz. While my brother was wrenching on his c6 supercharged vette (it was a bad azz car...599 to the rear tire) i told him...you reach a point in your life when you don't want to wrench anymore...you just want a fast, dependable car under warranty...imo the v12 s-class is the answer for people over 6' tall. i'll let jason post the good pic's but here's a teaser pic...

btw...the 65 was walking me good...amazing how driving a car hard can make such a HUGE difference!!!

 

Good looking car.

 

I'm lucky to have a S600 and a CL65 which must be similar to a S65.
Both are run on premium fuel. Beleive it or not the car learns how you drive.
Apart from better throttle response on the CL65 the power does not feel
vastly different but!! because I tend to drive it without passengers it's use
to being driven hard whereas the 600 normally has passengers and is being driven slower. However one day I took the 600 out and thrashed it, when I finished the brakes were moaning but the car felt like it was better than the CL. Also he's right, leave em for a week or more and they drive like crap.
It;s a bit off putting after a long drive cruising slowly I went for an overtake,
I had to brake and pull back, the fire had gone because of my slow cruissing.
To compare both cars they need the same fuel, and a good thrashing before
comparisons can be made. Sorry if I bored you.

 

Nope- no bore at all. My situation is a perfect example of what you've stated. I'm here to tell you, my 65 had to have gained 75-100HP over the 3 days of test driving.....and I have 2 witnesses to back it up. To go from losing badly to a 600, to walking off on one, takes a serious increase in HP. And, a few other AMG owners that I've talked to agree 100%. That being said, I don't plan on letting my car sit very long