Best option for SL400 remap/tuning?

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Now I'm confused, I thought the 2014 SL400 was a 3.5 Single turbo giving 302 bhp, the 2015 was a 3.0 twin turbo giving 333bhp and in 2016 the facelift 3.0 twin turbo pulled 362bhp?

I have a 2015 model which is 3.0 twin turbo and 333bhp.
Hi , from what Mercedes told me 🤠 apart from the piston size the real difference is that on the M276 3.0
engine , fuel pumps and the list goes on are based on upon high pressure architecture and in the 3.5 engine use low pressure components.

Again I understand that the 3.5 lump does have better fuel consumption but by how much I have no idea.

Mercedes M276 engine were available as a normally asperated with various out puts.
 
FWIW I didn't think the 3.5 ever made it in the SL I thought it only found it's way into the E class chassis. Could be completely wrong though.

I just found the before/after of my car....(mine was the 3.0 V6)

I immediately had to fit new tyres. The P Zero's were simply not up to the job. I couldn't get PS4S in the rear sizes they just aren't made. So I went with Pilot Super Sports the predecessor to the PS4S, in MO spec designed to fit the SL65AMG. Completely transformed the car.

The torque increase made it feel like a much larger capacity engine. It drove like a V8 instead of a restricted V6, that's really the best way to describe the change.

I had a C7 Audi S6 at the time which was a 4.0TT V8 circa 480hp the SL had the same pull from low revs as the Audi after the remap. It was so much more comfortable to cruise and drive slowly and it got rid of the awful hesitance that was caused buy the combination of the gearbox and powerband in the early 400 models.



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Well, the numbers are in....

Baseline dyno run:
328.93 HP
507.34 Nm

After tuning:
428.65 HP
600.66 Nm

So that's an increase of 100 HP and 93 Nm. Not bad at all.

The extra torque and horsepower are all throughout the rev range, with max torque at an extremely drivable 3,500 RPM. Previously it was at 4,500 RPM.

On the original HP curve, you can see that the HP was limited by the ECU from about 5,000 RPM. Now it climbs steadily up to 6K RPM.

I had a good old chat with Ant at GAD. He's very knowledgeable and I learned a lot about the SL400 motor, turbo and ECU combination.

The car is a 2014 SL400 - 3.0L, V6 Twin Turbo by the way....

It was a lot of fun on the drive home.
 
...but maybe one day someone will mention a mod of some sort on this forum WITHOUT someone saying about insurance within a dozen posts like all the posters are too stupid to realise!
Nobody is suggesting the OP or any other owner who modifies their car are stupid. A well timed reminder might save the owner a bit of grief should the worst happen and they did have a claim, later refused due to non disclosure.
Like you and your exhaust mod, maybe it "slipped their mind";)

I'm sure you can recall the unfortunate owner of an E63 that had a previously added wrap have a claim dismissed because he hadn't declared the wrap, even though he have the modification carried out himself? Bet he'd have been grateful for a reminder to declare all mods?

I'm not having a pop at you, but just explaining in my own way why I'll mention the insurance implications , especially having a remap before finding out whether their current insurer would accept it. Maybe, and its possible, it had slipped their mind.
 
there was only ever 1 engine in the SL400, the 3 litre V6 bi turbo in 333hp and 367hp (facelift)
 
Hi , I would have loved an SL400 but getting out of the car would be problematic for an old man.

My C207E400 has the M276 3.5 litre engine and I use Shell V Power when I fill up the car. The cars fuel consumption does improve on long runs.

Engine out put figures I have read that the torque value are much higher than Mercedes claim but the bhp values are edging towards 350 bhp.

What I have found don't drive the car to hard when cold because the gearbox oil take time to war up.Allow 15 minutes and the gear changes are seamless from my experience.

What ever you decide just enjoy your car
My Dad's E400 with the 3.5 litre engine made 352hp standard, and 417hp after mapping at MSL Birmingham. They're definitely underrated figure-wise from new.
 
What were the torque figures on your father's car, before and after if you don't mind me asking ?
 
could you describe how the driving experience has changed for the better please
Basically, more power throughout the rev range. The car now wants to hurl itself down the road more rapidly in Sport mode and is less "woolly" in Eco mode.

I was talking with GAD about the different Sport and Eco modes and whether they could change the characteristics of those or not. The answer was not really as they are mainly down to the transmission and not the engine. A transmission remap could change the characteristics of the drive modes though...
 
Basically, more power throughout the rev range. The car now wants to hurl itself down the road more rapidly in Sport mode and is less "woolly" in Eco mode.

I was talking with GAD about the different Sport and Eco modes and whether they could change the characteristics of those or not. The answer was not really as they are mainly down to the transmission and not the engine. A transmission remap could change the characteristics of the drive modes though...
Thanks.

I have always thought Sport mode to be too hyperactive, almost ADHD. Rarely use it. Brisk driving is better for me in manual mode.

Apparently no one has managed to break into 7G tronic box ECU to remap it ..
 
Basically, more power throughout the rev range. The car now wants to hurl itself down the road more rapidly in Sport mode and is less "woolly" in Eco mode.

I was talking with GAD about the different Sport and Eco modes and whether they could change the characteristics of those or not. The answer was not really as they are mainly down to the transmission and not the engine. A transmission remap could change the characteristics of the drive modes though...

I have been out for a bit of a play this morning and to add to the above, it's quite easy to feel the extra torque coming on at lower RPMs, which makes the car more fun to drive without having to press the pedal so much in Eco mode to get a decent response. It's also better in Sport mode as you don't need to go as far as lockdown to encourage it to giddy up properly. All in all, a nicer car to drive.
 
When I had my 204 C63 mapped I spoke to my insurer first (NFU) they asked for an extra £50, I thought that was ok so went ahead with it.
 
Thanks.

I have always thought Sport mode to be too hyperactive, almost ADHD. Rarely use it. Brisk driving is better for me in manual mode.

Apparently no one has managed to break into 7G tronic box ECU to remap it ..

Well, I had the gearbox flash remapped today. What a difference that makes.

Eco mode is much more engaging. It accelerates faster and stays in gear longer. It still gets to D7 pretty quickly after you lift your foot a little, but it is much more fun to drive around towns and villages. Previously, it was a bit of a limp blanket unless you really stamped on it.

Sport mode is amazing now. It stays in each gear quite a lot longer and the car is now seriously fast. Playing on private roads today it amazed me how quickly it got up to 120mph with no effort at all.

Manual mode is also greatly improved. The speed of the changes in response to inputs is much quicker.

All in all, with the engine tune and the gearbox remap, it's a totally different and much better car to drive - it has been weaponised!

I am very happy so far.
 
Interesting.....

Who did the gearbox flash?
What does it involve?
What is it to do?
And what does it do with paddle shift changes (snappier also?)
 
Interesting.....

Who did the gearbox flash?
What does it involve?
What is it to do?
And what does it do with paddle shift changes (snappier also?)
It was done by JF Automotive in Maidstone. £277.

It's very, very simple. They just plug an OBD device into the OBD port which lets them flash the TCU. Very similar to engine remap in that the gearbox also has a set of lookup tables in it that tell it at what revs to change up/down under particular conditions, torque limits, etc.... Takes about 30 minutes max.

And yes - paddle shift changes are much snappier. In fact, the whole car is much snappier in all modes. I am really enjoying the increased performance, especially in Eco mode which was rather too slow and wooly for me. Now it responds much better at low speeds, but still gives the economy benefits of higher gears when cruising.
 

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