Fuel Saving Remaps

[turbopete]

So no links then to these articles you were so sure existed.
And get your facts straight: I like remaps very much and have said clearly that they can improve performance. I do not like false claims backed by no proper scientific research. Chips do not give 15% better fuel economy however much you care to be abusive. Find some proof and I'll recant with pleasure.

IF (and its a big if!) i ever get mine chipped, i will visit stafford again, at 70 on the cruise control again, steeing off at 7pm on a saturday night again. just to see what happens. made the trip before, brim to brim and worked out 39.2mpg. would be interesting to do the same run at the same speed at the same time on the same day of the week at a similar time of year with the aircon in economy mode again, just to see if it makes a difference. because im as curious as anyone to find out if its true or not!

 

[hawk20]

IF (and its a big if!) i ever get mine chipped, i will visit stafford again, at 70 on the cruise control again, steeing off at 7pm on a saturday night again. just to see what happens. made the trip before, brim to brim and worked out 39.2mpg. would be interesting to do the same run at the same speed at the same time on the same day of the week at a similar time of year with the aircon in economy mode again, just to see if it makes a difference. because im as curious as anyone to find out if its true or not!

Now you are talking. That is exactly the kind of scientific control of conditions that is needed, plus tyre pressures, and so on. Very difficult to get road conditions the same. So much easier for experts to do numerous runs with several different cars on a track under controlled conditions. Given reasonable scientific proof of 15% fuel savings, every car magazine and TV programme like Top Gear, Fifth Gear and even the national news would cover the story. And sales would rocket. Makes you wonder why it has never happened, doesn't it?

 

[turbopete]

it does. im always a sod for checking pressures before a long trip if its more than a month since they were checked. i know ou should do them every week, but how many people ever bother? or even know your meant to? not many id bet! yes there will be some, but as a percentage of the driving population, id say very few indeed!

 

[*Thumper]

Wind ya neck in you rude little man !! ............... This thread is far more interesting, than you ! ............... Trolling gets a little boring after a while !

No more food !

 

[roadhog]

Finally this thread is getting interesting and I don't mean hawk and Thumpers little tiff.
Full credit to Steve for putting his money where his mouth is. I'll await Sam-Unit's review with baited breath.

@hawk, either of these links enough for your promised donation to charity?

http://www.autoexpress.co.uk/buying/buying/203578/chip_the_engine.html

http://www.autoexpress.co.uk/news/autoexpressnews/217497/bmw_535d.html

http://www.autoexpress.co.uk/news/autoexpressnews/229392/the_mpg_boosters.html

OK, so the last one only talks of a 14% gain but I figure that for the sake of charity you won't mind a measly 1%.

 

[keith100]

Wind ya neck in you rude little man !! ............... This thread is far more interesting, than you ! ............... Trolling gets a little boring after a while !

No more food !

Such an elegant turn of speech.......charmingly expressed.

 

[jberks]

Well, what can i say??
Evolutionchips who do my maps are part of motorsport developments who have been in the industry of modifying and tuning for many years, and are regarded as one of the best in UK..
I have never been on a forum where there is sooooo much negativity regarding remapping!
I could understand it if you had personal experience of a "bad" remap or didn't get what you were promised from one.
So, with such negative comments it's no wonder I haven't had anyone requiring a remap off these forums.. But you probably think that's good as your saving someone from having spent there hard earned on such as us, who is really trying to earn a living the same as anyone else.
And the good bit is it's my money that pay's to advertise on here at over £200 per month.. very well spent isn't it!!!

I'm not negative about a remap - actually, truth be told, I want one but same old story - been a lousy year and no spare cash at the moment.

What I'm interested in on a purely scientific level is whether there is such a thing as a remap that provides improved performance WHILST improving MPG on an Automatic. I haven't read the reviews but I imagine they're passat tdi manual type stuff and as I've said, it makes perfect sense to me that if you change up earlier and stay in top longer, utilising the extra torque you should see better mpg.
I can understand how one OR the other is possible. As PSMART says, you can detune just as easily as tune up, but, how can you achieve both at the same time unless the manufacturers have screwed up, which is unlikley.
I have come across firms that offer a device with 3 maps in it. The orginal, a performance one and an economy one. Makes perfect sense to me. But what I, and Hawk, struggle with is how both effects can be achieved at the same time on a car such as mine with an auto box that isn't going to change up until its ready.
I'm not saying its not possible, just that I don't understand how it could be.
Can you explain?

 

[psmart]

This thread is hotting up nicely

Anyone needing to save on cash, just disable the turbo, on the CDI2/3, simply a matter of pulling the electric connector off on the BPCVT (front left, two pipes going into top, an old style fuel filter hanging down from bottom). Performance is crap, but economy is good. Basically, engine goes into a 'safe mode', but on a 270, its good for 85mph.

On the ML270, original version, Mercedes made an auto and manual. The mpg figures for the auto and manual were almost identical and research revealed that the manual box couldnt take the torque (hence me not opting to have the C220 remapped). In order to reduce the torque, the 'map' in the manual 270 gave lower mpg. This is a Mercedes fact, same car, different box, different ECU tune. Thus, just putting the auto 'map' into the manual will give better mpg (...at the cost of a dead box).

Mercedes wont have pushed the limits on the tuning of their cars for many reasons, such as use of cheaper materials limiting torque (as above) etc. Primarily their in business to make money and if the auto boxes or drive train packs in during warranty due to excessive power, they wont make money, so not just fuel quality, servicing etc, theyll also detune for longevity.

 

[turbopete]

I'm not negative about a remap - actually, truth be told, I want one but same old story - been a lousy year and no spare cash at the moment.

What I'm interested in on a purely scientific level is whether there is such a thing as a remap that provides improved performance WHILST improving MPG on an Automatic. I haven't read the reviews but I imagine they're passat tdi manual type stuff and as I've said, it makes perfect sense to me that if you change up earlier and stay in top longer, utilising the extra torque you should see better mpg.
I can understand how one OR the other is possible. As PSMART says, you can detune just as easily as tune up, but, how can you achieve both at the same time unless the manufacturers have screwed up, which is unlikley.
I have come across firms that offer a device with 3 maps in it. The orginal, a performance one and an economy one. Makes perfect sense to me. But what I, and Hawk, struggle with is how both effects can be achieved at the same time on a car such as mine with an auto box that isn't going to change up until its ready.
I'm not saying its not possible, just that I don't understand how it could be.
Can you explain?

going by what ive learned about chipping over the months ive spent on here, when you remap the engine ecu, the auto box ecu is also remapped. the result is that the engine has more power and torque (and performance) and the gearbox is reprogrammed to recognise this and the fact that it doesnt need to downshift as much! things ive noticed in my time driving an auto is that they

1. downshift when they dont need to (when overtaking with plenty of room to spare)
2. often downshift more than necessary (instead of 5th to 4th at 65mph for exaple when in a hurry, an auto will go 5th to 3rd! then almost immediately back to 4th!)
3. are easily confused (driving along, take my foot off and slow down for a roundabout, see a gap so put foot back down and engine revs till box decides which gear it needs. this has happened in every auto ive driven so far!)

if a remapper can program some of that out of the gearbox, you are goingto save some fuel anyhow! how much i dont know. but in reality, you could probably just have your box remapped. power etc would be the same for the engine, so no increased stress there, box would behave more like it would if you were in control as you are in a manual. in fact, this is probably the reason why theres never been an auto yet thats been better on fuel than the identical car with a manual box. thats why, if i was to buy new, id not pay the extra 2k for the optional auto, if a manual is available!

 

[jberks]

theres never been an auto yet thats been better on fuel than the identical car with a manual box. thats why, if i was to buy new, id not pay the extra 2k for the optional auto, if a manual is available!

If they do remap the gearbox that may help, but then it would stunt the extra performance so its still a trade off. An auto is less efficient than a manual as it has hydraulics to run which sap power, there is energy lost in the torque converter until it locks and, aside from the latest 7speed boxes, a manual normally has more cogs. But then an Auto is sooooo much nicer to drive - I wouldn't swap back. Just driven the wifes car in this morning. It goes well with lots of torque allowing very early upchanges, and the gears and clutch are nice and light, but even then, its still more work to drive with 6 cogs to trawl through.

 

[turbopete]

If they do remap the gearbox that may help, but then it would stunt the extra performance so its still a trade off. An auto is less efficient than a manual as it has hydraulics to run which sap power, there is energy lost in the torque converter until it locks and, aside from the latest 7speed boxes, a manual normally has more cogs. But then an Auto is sooooo much nicer to drive - I wouldn't swap back. Just driven the wifes car in this morning. It goes well with lots of torque allowing very early upchanges, and the gears and clutch are nice and light, but even then, its still more work to drive with 6 cogs to trawl through.

which is why you get the extra power. it overcomes the lag of altering the gearshift pattern so it still goes better, but because of the gearshift data change and other factors, better economy too. id love to be able to remap cars! i can buy the kit off ebay, but without the right knowledge, i could ruin, not improve the ecu's

 

[sr-performancelive..]

Morning boys,
Pete never use anything for tuning your car off ebay.. I have had to remap a few cars now that have had cheap maps on.. they really are that bad..
I recently mapped a ML270 auto, owner says it is transformed now, pulling so much better at low rpm and doesnt kick down when it wants to, and 5mpg better.. brim to brim check.
I remap many auto's and tend to find nearly every owner complains of the delay when pulling away from standstill or the car changing down gear when it doesn't need to..
A remap really does transform them..

 

[SQ_W211]

if Colin sees improvement in the car after the map then i will get mine remaped too.

Thanks Cole for volunteering....

 

[hawk20]

hawk, either of these links enough for your promised donation to charity?



http://www.autoexpress.co.uk/news/autoexpressnews/229392/the_mpg_boosters.html

OK, so the last one only talks of a 14% gain but I figure that for the sake of charity you won't mind a measly 1%.

I've just read the last one by AutoExpress. Shameful piece of work.
a) samples of one rarely allow scientific conclusions
b) they make the childish mistake that JBerks refers to so well in an earlier post and take the fuel economy readings from the cars computer read-out, which as he explained is altered by the fitting of the remap.

Later I'll try and find time to read the other links you kindly gave. Hope they are better. Need samples of several cars, under controlled conditions, with proper tankful to tankful tests (or metering of fuel useage not based on the instrument cluster read-out).

 

[psmart]

...the fuel economy readings from the cars computer read-out, which ... is altered by the fitting of the remap.

CDI - High pressure pump pressurising a common rail feeding an injector. Pressure is determined by engine RPM.
Injector - known orrifice size (or dosing) - if ECU is coded correctly, manufacturing discrepencies are taken into account so ECU knows for a given pressure, bar temperature and time, the exact quantity of fuel used. After all, its measuring the air, temperature, turbo pressure, charge-air temperature and calculating the amount of fuel needed, and hence the orrifice opening time.

Thus, for a given pressure into a given orrifice size for a given time period = dose A
Re-Map:- pressure hasnt changed, orrifice hasnt changed, just time (and potentially charge pressure) = dose B

Vehicle distance travelled per given time period not changed, sensors not changed.

Thus, why would a computer, which is performing the dosing, not know how much fuel it injected in dose A and dose B? Is it a Freudian guess? No, its almost exacting science.

So, how can a trip computer mis-read? Perhaps it looks at the stars, decides its a Libra and gives a balanced guess........??

If the re-mapper tells the ECU, by injector coding, that the injector doses less or more than it actually does, then yes, it can misread, but why would a re-mapper need to do this, given they can control the time the injector is open?

 

[roadhog]

I recently mapped a ML270 auto, owner says it is transformed now, pulling so much better at low rpm and doesnt kick down when it wants to, and 5mpg better.. brim to brim check.
I remap many auto's and tend to find nearly every owner complains of the delay when pulling away from standstill or the car changing down gear when it doesn't need to..
A remap really does transform them..

Can you confirm that you alter the gearbox ECU as well as the engine ECU? Or is the improved drivability due to the changed engine parameters?

 

[hawk20]

Just read through this - bit of a marathon.
A couple of thoughts.
Remaps work by a mix of 2 things - increasing the length of time the injectors stay open and sme fiddling with the turbo boost.
Now, the reason most people see an improvement in MPG is that they rely on the computer. The computer is pre-set to expect a certain amount of fuel to be injected per injector pulse. Post remap, the pulse now injects more fuel, the computer doesn't know this and so underestimates the fuel added.

.

Try this from JBerks. P9 Posting 83.

 

[sr-performancelive..]

Most are due to engine ECU mods rather than gearbox...

 

[roadhog]

So you don't alter the gearbox ECU at all then.

 

[Alex Crow]

here is a question, a vehicle produces a certain amount of power (eg that needed to cruise at 70mph in car X) at a certain rate of fuel consumption, all steady state assumptions here................anyone know where i am going next?

how can we suddenly use 15% less fuel to make the same power? same engine rpm, same bhp produced, same mechanical losses. the conclusion is that it is only possible if the engine was not combusting all of its fuel in the first instance. with a diesel, as many here will know, that means lots of black smoke. 15% overfuelling is a lot and the smoke produced would be chronic.

there is no such thing as a free lunch, think about it. extra power from a re-map is a verified and believable claim, but 15% fuel saving? how? throttle back the fuel by 15% and you loose 15% power.

fuel savings may be possible by optimising injection firing point, tweaking egr function, turbo boost, deceleration shut off and gbox changes, maybe even the shut off flaps, but never by that 15%.

i don't believe in horroscopes, magic or religion either btw. i hear there is a million dollar prize for any proof of supernatural phoenomena of any kind, demonstrated under SCIENTIFIC CONDITIONS. the prize is yet to be claimed, though many believe in all the things above.................