Rambino951

1st off.. Do they come with an LSD?

2nd. Is there any company that would offer a Manual conversion, I will never drive an automatic unless its like an SMG or DCT etc.. but no fake automatic paddle shifters..

3rd. What other companies besides Renntech offer a nice ECU upgrade for more power?


Many thanks for the help.. cheers

whoover

Yes, an LSD is standard. No, a manual conversion is pretty close to impossible for lots of reasons. If you'd never drive an automatic an SL is probably not the car for you in any case. Yes, there are other ECU tuners, including sponsors of this forum.

kokanee

Not sure how much of an ECU boost is needed on a 65. I would think that it would be hard to drive without a LSD since the 600 is already bad enough without one.

maxabo

I was pretty convinced that my first SL600 from 2004, had LSD.
There was never ever only one skidmark after taking off! Allways 2. Even in turns.
Quite the opposite to the S600 TT i had before that, that in 30% of the cases made only one skidmark. And that is so embarrasing!

Then, my second -04 SL600 was also acting as if it had LSD (NEVER left only one skidmark). But I was later on told by a mechanic that then checked it out, it hadn't LSD..!

And this last SL600 (-05) from Carlsson, does react the same way as the others. Can't tell a difference in behavior between any of the three.

So what I'm getting at is, the SL600 is acting exactly as if it had LSD. Trouble with grip, sure, but it leaves ALLWAYS two stripes...
And isn't that the hole point with LSD..?
Or what am I missing..?

Hawker

I do not believe there are many manual transmissions that could handle the torque of the SL65 and there are few drivers that could be quick enough on the first to second shift. 738 ft. lbs. @ 2000 rpm is no joke! The LSD is standard and the car would be un-driveable without it. If you want a manual stick with a Porsche and watch the tail lights of an SL65.

The SL65 is an incredible car. It is absolutely the best combination of style, elegance, comfort and performance all rolled up into one car. Drive one and you will not care about a manual transmission.

As far as an ECU upgrade there is no need for one unless you plan to use the car on the track. Street tires are no match for the torque as it is.

kokanee

My 600 leaves 2 stripes. My dealer said they think it had LSD. The way the tail end kicked out my friends thought it had LSD. I just had it replaced with a Quaife LSD. I have the old one in the garage. It is an open diff- not LSD. I think the traction control of the SL is what was trying to stop the spinning wheel. Needless to say it is very different today! As has been said it this forum it is probably the first and most important mod to make on most SL's.

maxabo

I'm no mechanic nor a traction-expert, but if a car leaves two stripes, then the problem must be the tires. To me anyway...
Simply put, the problem can't be between the gearbox and tires, but the tires and the ground... Basicly speaking.

I'm not calling you a liar, when you say you are noticing an improvement in grip. I just can't get that one threw my head...

The only way I see, to put an end to the burnouts without changing tires, is to decrease power/thrust/torque.
And the hole purpose with a LSD, is of course to distribute even more power on to both wheels! But with both tires allready getting enough, there can't be a use in putting a LSD there...
Because the car cannot usefully distribute more power to the wheels than it allready does, when there are 2 stripes left on the ground...

That's what my common sense tells me today. Not to say I can't be convinced of something else...

Marcus Frost

Maxabo/Kokanee,

I had a 2004 SL600 with RENNTECH ECU. With the ECU the car was rated to have similar HP and TORQUE specs to an SL65. I can assure you that my car did not have an LSD from the factory and even if it did not leave 1 track, the fact that it would always violently "kick" the back end out on hard acceleration is a really good way of showing the car did not have an LSD. With LSD the car's backend will come out but it's much more controlled and stable.

A great selling point for the 65 is the factory LSD, I think that the biturbo V12 is in desperate need of one!

-m

kokanee

The 600 stripes could be called an stretch as the traction control cuts out all excessive spinning. This is true even when esp is turned off. So the stripes are really a couple feet or rubber that is gone from the road in a few days. This was true with the Michelin Pilot sports and now the p-zero Rosso's. I believe the traction control is fast and good enough to try to stop the spinning tire with the brake. The traction control in the on position is so good you cant get the 600 sideways, no mater what you do. In the off position it will let the tail wag a fair bit before shutting you down. Regardless of why the traction control cuts in a whole lot less in the dry now and tons and tons less in the wet. The 600 is nasty poor for traction in the wet as the traction control was always on.
What would the difference be in the 0-60 or 1/4 mile? Seems like a few 10ths at best to me. I can definitly jump on it harder and sooner with the LSD than without. I've been told that the Quaife is a 100% locking LSD. I would question the sanity of anyone who doesnt believe a good LSD provides better traction than an open diff and with a 600 ft-lb engine . Everyone was telling me the 600 had an LSD already (Including the dealer's mechanic), but it sure didn't. I can't explain why the back end kicked out like a posi nor the two short stripes, but is a very different car now. I can see why the SL65 has an LSD from the factory. It would be hard to drive otherwise.

Rambino951

Well I am an avid tracker, and a purist with an addiction to power.

For the ECU upgrade, i dont care if it puts out 1000hp, i love power and the more of it I have the happier I am.. Of course i realise there is a point where it becomes unusable, but it seems Renntech so far gives me the best power upgrade from stock.

For the Manual transmission, as said im a purist, i like to be in control, i like to switch my own gears, I dont like the automatic tranny kicking down, limiting my rpms range, switching for me when i hit redline etc... Can anyone tell me what the Renntech Tranny Programming does? Does it give the driver more control and remove some of the automatic nonsense?

For the suspension, im assuming the Lowering Electronic control device is the best way to go.. How does the Sl65 fair in the bends with this? are there any other available upgrades such as a suspension setup or adding bigger sway bars?

Finally as far as the traction control.. Is there anyway to turn it off completley or have it programmed to do so? I do enjoy the occasional drift.

Thanks for all the helpful info so far..

maxabo

Generally speaking I think EVERYBODY agrees on, that an LSD equals better grip!
But, that must be because most cars with an open diff, in most cases leaves one wheel spinning...
And in THEM CASES (99 out of 100), an LSD is a must have. Absolutely!

But, since the SL600 some how is incapable of having one wheel spinning, I really don't see the point in LSD. But that's just me.
That's what I ment.

And personally, I find it VERY VERY hard to understand how the SL600 without LSD can behave as it does...

maxabo

[QUOTE=Rambino951;2679215]
Finally as far as the traction control.. Is there anyway to turn it off completley or have it programmed to do so?QUOTE]

I'm turning mine of by having the key in the ignition mode.
Then press the reset butten 3 times quickly.
Then there comes info to follow in the display.

It was a while back, but something like that...

Good luck.

kokanee

Ever see the video comparing the ML63 and the Porsche CTT? It shows an ML driving up a hill with one wheel free in the air. It would rotate a degree or two, stop, rotate a degree or two, stop, rotate a degree, yada yada. This is the traction control. If one tire spins faster than the other the traction control puts the brake on that wheel to slow it down forcing an open diff to provide power to the non spinning wheel. Its quite effective and extremely fast acting. But the fact is the brake is robbing power being applied to the wheel(s). If you can prevent the traction control from coming on during heavy acceleration you have pure power to both wheels rather than partial left, partial right etc. Perhaps my understanding of the system is wrong or perhaps the explaination is wrong. I do know that the SL traction/stability control is quite intrusive and very good say in comparison to a Mustang GT. It is very hard to get into trouble, even in the wet with a novice driver, in the SL with it on.

whoover

The Renntech (and other tuners') ECU mods mainly remove the factory torque limiter, which limits boost to prevent the engine from delivering more than 738 ft-lbs. This equals 1000 Nm, which is the transmission certification. Without the limiter, the engine will produce almost another 100 ft-lbs in the midrange. A little remapping will move the torque peak a little higher to maximize peak horsepower.

Of course the limiter was there primarily to protect the transmission; furthermore, the transmission itself senses overtorque and protects itself. This is why TCU modification is needed as well. Some of it is supposed to match the remapped engine's characteristics, but I understand it's also needed to allow that extra torque to make it to the wheels. Whether the drive train survives the extra torque depends on how often you use it.

The SL65 is not a great track car by any stretch of the imagination. The engine is very heavy, and the car is bound to exhibit a certain amount of understeer. Because it has ABC (an active suspension), there are no anti-roll bars. Again, what suspension tuning can be accomplished takes a programmer.

ESP cannot be completely turned off on this model, although it can on some new models from AMG.

The new SL63, with better weight distribution, multi-clutch transmission for faster manual shifts and ESP that can be switched off will probably track rings around an SL65, although nothing beats the SL65 for getting on a freeway with a huge grin. AMG makes better track cars (a CLK BS, for instance), but other marques will always beat these.

Rambino951

thanks for the helpful info..

as for the TCU mod, does this let me hit the revlimiter or will the car always automatically shift up top even in manumatic mode?

as for turning off the traction control, im assuming there Must be a way.. the guy above said something about pushing the reset button 3 times.. im sure someone has to have a fix for this..

cheeers

whoover

Behavior at redline might be a function of the exact year and version of the TCU software. I don't know if the Renntech TCU changes the factory behavior. I do know that my wife's C55 just bounces against the limiter at redline but my S65 upshifts at redline in any mode, even M. (They're both 2006s.) And yes, there is a dyno mode that turns off ESP. But it also turns off ABS and is not recommended for anything but engine testing. People have done 1/4 miles runs with it, but it would be pretty inadvisable to track the car in dyno mode. This is why they added a three-mode ESP (On, Sport, Off) for the latest AMG models, including the SL63.

SL65amgOwner

I agree with the manual. I know that it would be more fun and you would be more involved in the experience, but you probably shouldn't be looking into the SL if you really want one. Its hard for me to say, but the M6 does offer an SMG, if that helps?

IngenereAMG

Rambino:

I just noticed this thread. There are allot of tuning options for the 65.

Our ECU work gives a nice kick in hp/tq, but I too am a racer, and I have designed our work to improve the power delivery and broaden the power band. In other words, we make all the power more usable.

Our TCU tuning is a bit different in that rather that increase the pressure inside the gearbox, my guys work with the algorithms to improve shifting speed. This process is proving to be a bit easier on the gearbox.

I understand your frustration with not having a manual box to work with, as I like shuffling them myself as well. I don't think that I have ever driven my SL55 in auto mode. I have found that these gearboxes when driven consistently in manual really learn the way that you drive and the way you want them to shift.

We lower each car individually through the Star diagnostic system. So, as of now, we can only do this in AZ.

Feel free to PM with questions or email directly.