Remap worth it ?

[Nickthepie]

Hi I’ve currently bought a CLS250 cdi AMG Sport 2012 , I’ve seen quite a lot of places all offering the same service to remap the car and claim it goes from 201bhp to around 240bhp , everyone is claiming that this is safe and it won’t put too much stress on clutches and other parts .
I quite like the idea of giving the car that little bit extra but don’t want to cause myself any problems is it worth it ?

 

[Gazwould]

Except it won't get to 240 bhp because it never had 201 to begin with .

Nominal gains of 35 - 40 bhp and 50 - 65 Nm are the average .

 

[alexanderfoti]

It is possible to get 240 bhp out of these, but it depends on the DPF version. Earlier ones are much bigger and present less of a restriction. Later ones (eg 2012) will present too much backpressure at 250bhp ish, depending on its internal condition and miles.

A good map will not give any issues and will also increase fuel economy by 3-5% minimum.

 

[Rotorhead500]

Weren't there a few issues issues with mapping the 250 CDI? I'm sure it was already in a fairly high state of tune around then, and a few members had to have their's unmapped to resolve issues...

May be worth a chat with @GAD Tuning LTD or Alex @AMF Automotive...

Edit: Ahaaa! There he is, above. We must've crossed in the ether!

 

[Gazwould]

There was something , probably fuel pressure related and a limp mode ?
All sorted now .

240 - 250 all depends on how 'generous' the dyno is !

 

[rorywquin]

.............

A good map will not give any issues and will also increase fuel economy by 3-5% minimum.

Serious questions .....

Does that mean less fuel used or more?

If remaps are so good, why don't the cars come like that from the manufacturers. If it is because of emissions, then remaps should be illegal shouldn't they?

All the (remap) providers say, no damage, improved consumption etc. In fact reading the blurbs, I cannot see a downside to doing a remap so I am confused as to why MB sell cars that underperform and use excessive fuel!

 

[Rotorhead500]

Serious questions .....

Does that mean less fuel used or more?

If remaps are so good, why don't the cars come like that from the manufacturers. If it is because of emissions, then remaps should be illegal shouldn't they?

All the (remap) providers say, no damage, improved consumption etc. In fact reading the blurbs, I cannot see a downside to doing a remap so I am confused as to why MB sell cars that underperform and use excessive fuel!

My understanding is, it's primarily to get a standard engine tune that works out of factory for the various fuel grades / quality across markets. We have clean fuels, hence room to remap.

Pretty certain these days, it also gives manufacturers wiggle room to remap an engine, stick on a bigger badge and charge punters an extra £3k!

But I may be wrong. And a bit cynical.

 

[Blobcat]

Serious questions .....

Does that mean less fuel used or more?

If remaps are so good, why don't the cars come like that from the manufacturers. If it is because of emissions, then remaps should be illegal shouldn't they?

All the (remap) providers say, no damage, improved consumption etc. In fact reading the blurbs, I cannot see a downside to doing a remap so I am confused as to why MB sell cars that underperform and use excessive fuel!

They don't... a lot of remaps mean the fuel economy information is now more inaccurate as it still thinks the injectors are sending the same fuel into the engine when in reality to get more power they're sending more fuel in.

 

[alexanderfoti]

Less fuel

Engine maps are always a compromise. The cars must work across a huge temperature range (-40c +50c), varying fuel quality, In all conditions and have the same power output and performance.

By optimising the values for the local environment, we can gain power and economy without affecting other items. Cars tuned in the UK probably wouldn't behave so well in the desert in Africa and would probably misfire etc.

Whilst its true some parameters can be modified to increase power and also increase emissions, that is only a few of many parameters we chose to modify.

No damage is certainly true though, we have many engines that have done 200K + on maps I did 10 years ago still running strong.

 

[alexanderfoti]

They don't... a lot of remaps mean the fuel economy information is now more inaccurate as it still thinks the injectors are sending the same fuel into the engine when in reality to get more power they're sending more fuel in.

This is mainly true on tuning boxes and really old CDI cars (CDI 1 and CDI 2) for example. Most of the ECU's now read the fuelling data from the maps to provide economy data and is still fairly accurate. Always do tank to tank though, never trust the dash.

 

[Blobcat]

This is mainly true on tuning boxes and really old CDI cars (CDI 1 and CDI 2) for example. Most of the ECU's now read the fuelling data from the maps to provide economy data and is still fairly accurate. Always do tank to tank though, never trust the dash.

Agreed on the tank to tank, mine is 31.18mpg for 40K miles - dash is showing just over 32 mpg
You still can't up the power and use less fuel though, unless you've succeeded in perpetual motion...

 

[alexanderfoti]

Agreed on the tank to tank, mine is 31.18mpg for 40K miles - dash is showing just over 32 mpg
You still can't up the power and use less fuel though, unless you've succeeded in perpetual motion...

You can if you add more air to more completely burn the fuel

or

If you advance the start of injection to increase the power made by burning that same amount of fuel

or etc etc

 

[Blobcat]

You can if you add more air to more completely burn the fuel

or

If you advance the start of injection to increase the power made by burning that same amount of fuel

or etc etc

So Mercedes design their engines for an incomplete burn? wouldn't that give really bad emissions...

 

[Gazwould]

Diesel particulate wise .

 

[alexanderfoti]

So Mercedes design their engines for an incomplete burn? wouldn't that give really bad emissions...

or etc etc

 

[rorywquin]

Pretty certain these days, it also gives manufacturers wiggle room to remap an engine, stick on a bigger badge and charge punters an extra £3k!

........

Might be true but then they reach a point where latest model's (bigger badge) engine is giving max performance and the owner takes it in for a re-map....

Strangely the GLC 43 AMG has the same engine (and output) as my SL400 'AMG Line' and yet one is marketed as an AMG and the other not! (Now....where are those cheap AMG badges on Ebay.....)

 

[rorywquin]

...........

By optimising the values for the local environment, we can gain power and economy without affecting other items. Cars tuned in the UK probably wouldn't behave so well in the desert in Africa and would probably misfire etc.

........

Makes sense. Is the tune on my car identical to one that they would sell in Australia or Russia?

 

[Nickthepie]

Thank you for all the info guys , mine is a 2012 AMG Sport , as far is fuel is I always use the Bp Ultimate and my car has got 37k on it , only just purchased it in November so it sounds like it’s worth doing , with someone you trust , maybe I will check insurance first too to see what the additional cost would be , I declared a change of exhausts on my Hyabusa motorbike and it only cost me £10 more to insure

 

[Gazwould]

BP Ultimate... I could save you a fortune !

 

[Nickthepie]

It’s a lot cheaper than my old car still , it only costs me about £75 to fill up and I’m doing i think around 450 miles out of that , my old Audi A8 4.2 used to cost me £130 to fill and I would get around 280 miles