What is remapping? Is it really beneficial?

[Dieselman]

Your answer has zero to do with widebands.

Change the pulley, up the boost and remap from the other sensors that the Ecu uses (such as map).

So not just a remap...

 

[gerrym]

I disagree.

Good argument!

 

[V12]

More power = more diesel = higher temperature = reduced longevity. /QUOTE]

If you sincerely believe that equation to be true (in the real world) then there's little point continuing the debate.

How come the W212 E220 and 250 had identical economy figures in 2009?

Marketing is what drives everything these days, not optimum solutions.

Despite what others claim. CO2 banding is by far the biggest sales divider at the moment. Does anyone believe that Lexus just happened to end up at 99 for the new IS300 by chance?

Ok, as you seem to be more educated on the matter than myself, please correct my equation. Nothing comes for free.

220 and 250 have the same mass, so need the same amount of fuel to do the same performance.
The 250 will use more fuel than the 220 if you are using 100% performance.

Of course manufacturers go to great lengths to reduce the g/km, obviously not just chance.
Some new volvos sneak into the lowest band just by loosing the weight of the spare wheel and associated kit. If you option the car with spare or with certain larger wheels with greater unsprung mass they end up in the higher tax bracket.

 

[SteveX]

So not just a remap...

That's true lol

 

[HumberMart]

Ok, as you seem to be more educated on the matter than myself, please correct my equation. Nothing comes for free.

220 and 250 have the same mass, so need the same amount of fuel to do the same performance.
The 250 will use more fuel than the 220 if you are using 100% performance.

Of course manufacturers go to great lengths to reduce the g/km, obviously not just chance.
Some new volvos sneak into the lowest band just by loosing the weight of the spare wheel and associated kit. If you option the car with spare or with certain larger wheels with greater unsprung mass they end up in the higher tax bracket.

The thing about theory is that it doesn't always transfer (intuitively) into the real world. Take cruise control for example; many may think that liberal use of cruise during a journey will help improve economy, but it actually worsens economy due to the computer constantly varying the fuel supply to maintain speed. Some 'theorists' will argue against this phenomenon, but it is true in practice.

Converting diesel into energy is similarly counter intuitive at times and complex. I guess most will accept that if they have a 20 year old gas boiler, it will not be as efficient as a properly set up new one. Just adding more fuel doesn't automatically mean more heat and energy.

Of course modern computer controlled diesel engines do a wonderful job of getting it right and producing 'near' maximum combustion efficiencies (as available from the hardware) 'most' of the time.

But to do this reliably across the rev range at all temperatures, would require (for example) fuel that was consistent within a much finer tolerance that from your average ASDA. You could go on of course, same wheel, tyres, tyre pressures, weight of passengers, humidity, etc etc.

Then we go onto the need for the manufacturers to get highest possible combined mpg, and lowest possible CO2. They can do this by preparing a map that is tailored to ensure the leanest possible mixture at the revs/points in time that are critical to the tests. This tends to result is the less smooth performance through the rev range than a stock car can exhibit, and one that is often 'cured' by a remap.

The gap between official mpg/CO2 figures and real world are getting wider and wider. It's now common for a 65 mpg official figure to see only 45 mpg in the real world. This is a further sign of how manufacturers are tuning to pass a test, not produce the 'best map'.

As highlighted before, many engines are effectively 'detuned' (solely by means of the map) by the manufacturers to meet marketing/legislative/business criteria. Surely this is absolute proof that remapping is a very real and useful tool.

 

[Stratman]

So how do you get more power by burning less fuel in the same engine?

 

[SteveX]

Ok, as you seem to be more educated on the matter than myself, please correct my equation. Nothing comes for free.

220 and 250 have the same mass, so need the same amount of fuel to do the same performance.
The 250 will use more fuel than the 220 if you are using 100% performance.

Of course manufacturers go to great lengths to reduce the g/km, obviously not just chance.
Some new volvos sneak into the lowest band just by loosing the weight of the spare wheel and associated kit. If you option the car with spare or with certain larger wheels with greater unsprung mass they end up in the higher tax bracket.

Co2, global warming, all companies are worried about it, IMHO the biggest scam of the 21st century.

I won't get onto conspiracy theories as people might think I am crazy (if they don't already lol), but, it's some crazy concoction made up by the government to impose a green tax on corporations mostly (although the general public also pays), carbon footprint my ass! It's all just to create a new revenue stream so they can waste more taxpayers money on things we don't need.

Last time I researched there was no, cast iron scientific proof that global warming exists.

Imagine if our civilization was a some thousand years prior, they would be coming up with some bull **** excuse to blame the ice age on man kind, probably 'Global Cooling'. In the history of mankind there have been many drastic shifts in our climate, oh, I rambling, too much Guiness and going on a forum, I shall be quiet now....


lol

 

[V12]

@ HumberMart, I appreciate you taking the time to reply and explain.

Replying on my phone so will keep it short.

We're not comparing an old boiler to a new one. We're talking about ONE boiler.

I'm not denying that maps have their place for some purposes. I'm not denying that more power is available or that the spread of power can be more evenly distributed.
What I'm saying is that everything comes at a cost.

Tuning companies make wild claims of releasing upto 20% extra power and a 20% increase in MPG with no side effects on reliability.
I regard lots of them as con artists personally.
The good ones are usually clear that they are just offering a performance service.

 

[jetboy]

Hi All,
Well I finally got around to posting.
I have owned my baby for 6 months and I have to say what a tool she is
Unfortunately I think since owning her I have developed an addiction to keeping her shiney and clean, even if it is wipe the brake dust off the wheels, as long as I stroke her every day I feel satisfied that she looks her best-but I wont go on about that so back to the topic.
I had mine re mapped a few weeks after purchase, I got easily dazzled by the claims of such an improvement on bhp and fuel economy but mostly by the amount of extra torque.
I jumped in with both feet but the one thing that I didnt think about was that my car is an auto and the extra torque would make the car kick down almost at the slight sniff of the loud peddle being prodded.
I had a heated discussion with the remapper afterwards to express by disatisfation which resulted in him offering to remove the remap and replace it with the original, by the end of the discussion I felt that I couldnt trust him so I decided not to take him up on his offer.
To conclude I would say that I felt like a school boy buying a packet of sweets and leaving the shop with an empty bag , I had been given x amount of extra torque but simply couldnt use it as the box kicks down too easily, the revs climb and the torque is gone.
With the benifit of hindsight and the lack of a time machine, for the above reason I would think twice before remapping an auto, unless the box could also be remapped.
Mark
ps and it still smokes when she gets wound up
pps sorry I couldnt do my first post without a few pics-as in the words of a famous hair product 'cos shes worth it'

 

[HumberMart]

So how do you get more power by burning less fuel in the same engine?

Have you ever considered that you can add too much fuel to an engine?

If you happen to have an engine that it being 'over-fuelled', then burning less fuel will make it more efficient, and may even actually increase the power.

 

[Stratman]

Have you ever considered that you can add too much fuel to an engine?
...................

Yes.

With manufacturers straining to meet increasingly stringent emission regulations, not to mention fleet buyers looking a decimal points with fuel consumption I doubt modern cars are overfuelled.

 

[boxbrownie]

You really need to do a litreage/receipt analysis of economy.
Indicated economy can be pretty wide of the mark after a remap, since the ECU thinks injectors are still passing the same quantities of fuel.

It's easy to shorten engine life with a remap - since mapping is an exquisitely complex proposition that even for manufacturers is as empirical (suck it and see) as it is scientific.
The dynamic interplay of so many parameters makes it a very dark art.
Remap at your engine-longevity's peril.

Presumably you sit in the Lords as well.....explains everything

 

[markjay]

The idea that manufacturers detune engines due to professional negligence is not serious.

Engines are detuned by manufacturers for a reason, either to improve fuel consumption to meet the demands of the frugal brigade (mostly taxis and fleet buyers), or to improve engine and transmission longetivity and reliability, or a mixture of both.

The idea that reliability and longetivity are binary is also not serious.

An engine with higher output will be statistically less reliable and will experience higher wear rate than an otherwise identical but less-setressed low-power one.

Said that, a 75bhp engine that sips fuel and can go to the moon and back without breaking down is not everyone's idea of a good all-rounder.

Remapping for more power can actually make sense, it simply shifts the balance between mechanical robustness and performance to a point that is acceptable to the owner.

But a high-power engine that lasts as long as its weaker sibling is a myth, just as is the one about 35 profile tyres on 20" wheels being as conformable as 55x16.

 

[MattWW]

Jet Boy - Sorry to hear about your experiences with Remapping.

I can assure you not all tuners are the same, when remapping a vehicle we always speak to the customer to fully understand their requirements before work takes place.

A remap should take into consideration all aspects of a vehicles performance. Fuel economy, power, power curves, drivability, gearbox characteristics and reliability, these are all major points that must be achieved in a map unless explicitly instructed by the owner.

Depending on your location I can happily recommend tuners with a proven track record and insurance to back up their claims.

Cheers,

 

[jetboy]

Matt,
I must be a one off complainer, according to the remapman, I am the ony person who has complained about getting more power.
The point I couldn't seem to get across to him was that my car has a big (ish) torquey motor which was partly why I brought the car and the extra torque would be greatly appreciated,
being able to prod the throttle and the grunt would just pull me from low revs, ie; around 2000rpm was what I wanted more of, in reality the car kicks down because the gearbox thinks I have put my foot down more than I actually have (according to the remapman).
Do you know of a gearbox remap to overcome this so I can use the torque rather than the top end bhp?
Can you see what seems to be happening and if so would you agree that this is what happens?
thankyou
Mark

 

[Dieselman]

The more torque the gearbox ECU sees, the higher the gear it will pull, so your remapper is talking B.....x

 

[Paul/]

...my car is an auto and the extra torque would make the car kick down almost at the slight sniff of the loud peddle being prodded...
I had been given x amount of extra torque but simply couldnt use it as the box kicks down too easily, the revs climb and the torque is gone.
With the benifit of hindsight and the lack of a time machine, for the above reason I would think twice before remapping an auto, unless the box could also be remapped...

Like you, I'd have thought that autobox mapping should be reviewed whenever there has been any change to the torque profile. I think it's easily done on the g-tronic using Star-type tools. Easy to do- but not necessarily easy to do correctly.

The overly-sensitive kickdown could be due to the accelerator pedal having been recalibrated to the throttle- like removing the spring on an older car, the impression of increased performance could be gained simply by reducing foot effort required to open full throttle (at the expense of the driveability issue you describe). Perhaps it's been done inadvertently? There's a common misconception that 7g box adaptions can be reset by manipulating the accelerator with the ignition in position X (I forget which). In fact that process just recalibrates the throttle between minimum and maximum pedal positions at the time.

 

[Dieselman]

The overly-sensitive kickdown could be due to the accelerator pedal having been recalibrated to the throttle- like removing the spring on an older car, the impression of increased performance could be gained simply by reducing foot effort required to open full throttle (at the expense of the driveability issue you describe).

That's all the map has done, much like a sprintbooster box.

I suspect the pedal runs out of any meaningful movement at further depression.

 

[Paul/]

That's all the map has done, much like a sprintbooster box.

I suspect the pedal runs out of any meaningful movement at further depression.

Interesting, I'm almost tempted to frig about with mine for a laugh- it probably makes the car less driveable, but at least it's a no-cost way to do that.

PS No, I'll give it a miss.

 

[Dieselman]

Interesting, I'm almost tempted to frig about with mine for a laugh- it probably makes the car less driveable, but at least it's a no-cost way to do that.

PS No, I'll give it a miss.

Just add a 20p resistor differential circuit to the accelerator potentiometer and you have a Sprintbooster.