I don't know how a map will affect your particular engine but in the remapped TD's I've driven MPG gets better rather than worse. I'd imagine your driving style will compliment the typical earlier power delivery you get with a map.
I can only say how a remap works with our MKV Golf GTi which is a petrol car equipped with DSG (kind of an auto) and the shift points seem unaffected while MPG is up by 2-3mpg on a typical run. Unless of course you use the extra performance in which case it is lower. I have to say though if you aren't planning to give it some stick on a regular basis you might find the cost/enjoyment ratio isn't worth it.
Personally I wouldn't have any forced induction car without a quality remap as it literally transforms the driveability and thus appreciation of the car. I've had numerous cars equipped with turbochargers and all have been improved by remapping. Why the manufacturers don't do this themselves can only be a matter of ultimate longevity and legislation.
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Bascially these modifications involve remapping the ECU - i.e. changing the various values in the software's look-up tables which represent a multidimensional 'surface' linking parameters such as fuelling volume, fuelling timing, turbo boost, degree of EGR etc etc.
They are only as good as the guy who writes the new data - if he gets it wrong then it can easily damage your engine or lead to drivability problems.
Values are typically arrived at by taking an example vehicle and running it on a rolling road and then 'experimenting' with a whole set of values at each engine speed/load point to arrive at what the technician feels is an optimum map set. I did this years ago for a major VM on one of their petrol engines. A VM's team of engineers will spend many months going through this process and then subjecting the vehicle to a whole range of durability/drivabillity/emissions tests to affirm the dataset. A 'chipper' will probably spend a day or two going through the process and playing with the code....
Some companies actually take your vehicle, put it on the RR and arrive at a bespoke map.
Overall you dont' get something for nothing and whilst it is very easy to get more power out of most production engines (esp turbo) something has to give, be it fuel economy, long term durability etc etc. Really, it all come down to the knowledge and experience of the people doing the job.
Incidentally, such a change is detectable. Perhaps not to the service guys (who would not normally interrogate the ECU's map data) but if the car were to be involved in a serious accident then the ECU might well be examined for signs of software or hardware modification. 'Chipping' has become commonplace on Diesels and I've no doubt the insurance companies are wise to it!
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">Some companies actually take your vehicle, put it on the RR and arrive at a bespoke map.<"
Which has to be the correct procedure.
Achieving a flatter bhp curve (forget torque, it's a nonsense) can make the car more driveable, particularly if the rev range can be extended for long overtakes, without adversely affecting reliability.
I prefer peaky, unforgiving power curves, but that's because I appreciate the driving/riding experience. 125cc MX bikes from the late '70s were wonderful.
"There it is!"
"What?"
"It's gone now"
"What's gone?"
"The powerband"
"Oh"
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MPG may drop then? Doe the remapping also affect the auto box gear changes ie later to shift up and down or is it all about the power conversion in the engine?
MPG may drop if you make use of the extra performance. A Diesel is inherently a lean-burn IC engine and so extra power is obtained by burning extra fuel. Remapping can get you a bit of extra volumetric efficiency, but by and large you don't get something for nothing.
In you particular car the transmission shift points will probably change a little because the TCM uses engine data (from engine ECU) to derive an instantaneous engine torque figure which it uses to determine shift point.
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Never heard such good sense spoken Aprilia. I know different-strokes-different-folks etc. , but why on earth change the engine map of a 320cdi when standard trim is at least 210 bhp & 500 Nm torque?
Hats off to the ECU tuning companies though, they've managed to persuade a fair constituency that they can reverse the laws of physics, i.e. you can go faster & use less fuel. Nice one!
What most of then don't say is that tweaked the 'use more fuel' messages sent to the injectors, don't tell the fuel usage computer that more fuel has been used, as is the case with 'in-line' chipping. I'm sure if the gleeful chip-ees actaully did an accurate brim-to-brim test the truth would be revealed.
The bottom line of most 'chipping' is a more peaky power delivery which uses more fuel (laws of physics again) together with more stress & resultant strain on driveline components.
If you really,really need to go faster, buy a faster (standard) car.
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210bhp and a bucket load of torque enough? You must be joking- in a car that's as heavy as a small house more power will always be welcome.
As I said earlier the reason remapping a car will often lead to improved MPG in normal driving is that with the best maps power comes in earlier (and smoother I might add- not in a spike as some people have suggested) meaning you have to use less throttle opening to achieve a given speed.
The results I found with my diesel PD150 engined car were around 2-3 mpg extra- confirmed by brimming the tank and noting the distance covered rather than relying on a fuel computer which was innacurate from the factory.
A lot of the comments here are based on ignorance and I'm sad to say knowledge that's at least a decade out of date.
What I do agree with is that remapping is likely to cause more stress to components which is why it's important to do your research, check out what the owner's forums are saying and who they recommend and see what problems have been found with a particular mapper.
In the case of DMS they are at the top of the tree- having been widely reviewed in most of the car magazines and have a reputation for excellence.
As for buying a 'faster car' rather than remapping, when I had my B4 there was no faster estate car on the market, likewise the PD150 was the most powerful engine in it's class- mapping them was the only way to get more power and as I said earlier you CANNOT have enough of that.
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I have had a tuning box fitted to my Saab 9-3 TiD for over 2 years. Most of my driving is boring commuting, much of this time I drive with a light-ish right foot and get 3 or 4 additional miles per gallon (calculated brim to brim).
When I do feel like giving it some welly it is a lot quicker than standard. My car being an old non-CR diesel, it used to have a bit of lag below 1900rpm. With the tuning box the lag is eliminated and it then goes better still on boost, with more at high revs too.
If you cane it everywhere you will obviously get less mpg, like you would in an unmodified car. A mate of my Dads had a chipped Touareg V10 Tdi, he sold it because he said it was too thirsty! But it is not a factor beyond your control, if you cannot drive with restraint then you are going to use more fuel, and you don't have any grounds to complain about it.
What is the downside; is there one? I suppose driveline components are getting a bit more stick from the extra torque, but I don't tear around all the time in it so that may be negligible. I was initially concerned about clutch wear, wrecking the injection pump etc., but I've done nearly 40k miles with no problems so far.
As long as you go with a company with a good reputation, and you keep up with regular servicing, I don't see a problem. If MB, Saab, Mitsubishi (and others?) are happy to give warranty cover to chipped vehicles, they presumably don't see a problem either.
There were complaints years ago on some cars about excessive black smoke on hard acceleration (with tuning box, not remap) so ensure that this is not the case with the options you are looking at.
Oh, and remember to tell your insurance company, the small increase in premium is well worth it for the extra power IMO. Depending on your circumstances you may not get an increase in premium. But do check because some of the mass-market insurers do not like it.
If I buy another diesel as my next car I will definitely be getting it chipped.
;o)
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@ Woodbines
If the car is driven in the same manner as before the MPG will improve, having more power will keep the car in a taller gear longer.
www.amdtechnik.com/technical.remap.cfm
;O)
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Having 'been there and done it' for vehicle manufacturers I feel that I am able to comment with some authority - sorry if that sounds arrogant, but as a professional engineer who has been working in the field since the late '70's its something I know a bit about.
Remapping can't change the laws of thermodynamics and thermochemistry - they've not changed, not even in the last 10 years. The power provided by the engine comes from only one place - stored energy in the fuel. You can marginally improve the engine's thermodynamic efficiency by remapping, but not much.
To talk about 'getting more power at a small throttle opening' on a Diesel engine is absolute nonsense - Diesels are not throttled, the argument just doesn't apply.
Under a light cruise ('steady state') condition the energy used in propelling the car is just enough to overcome frictional and aerodynamic losses. For a given engine configuration it is very difficult to improve the economy by any significant amount, expecially on a Diesel. On a lean burn petrol engine (e.g. Toyota) it is possible to improve economy a little further by very lean operation and hence the reduction of throttle pumping losses.
Where improvements ARE possible is under transient conditions, where additional fuelling, boost etc will really be felt by the driver.
Unfortunately far too many people think they 'understand' engines when in fact a proper understanding takes years to acquire. If you want to learn more then have a read of John Heywood's 'Internal Combustion Engine Fundamentals', which always used to be required reading for first year undergraduates.
You have to remember that the engineers who developed the original maps had to cater for a very wide variety of operating circumstances; e.g. everything from towing a trailer over the Stelvio Pass, to sustained 100+mph cruising in 40 deg. ambient on 92 octane fuel. And they have to ensure it meets emissions regs under all these circumstances, retains good driveability and lasts 100K+ miles.
Development takes many months and includes running in climatic chambers (high/low temp and humidity) and running prototype vehicles everywhere from Lapland to Death Valley.
It is not at all difficult to remap an engine to give more power, but at the end of the day some other parameter will be compromised. Few remapping companies have the resources to even approach what the manufacturer can do.
Several companies are 'manufacturer approved' (in reality its more 'importer approved') in which the new code has been looked at by the manfifacturer and 'approved' in the sense that they don't think it will cost them anything during the warranty period.
There are some very very good remaps out there, the big outfits with plenty of resources. What you must avoid is the 'mobile remapper' who comes around to your house with a laptop and loads a map he downloaded from the web! And then charges you £500.
As regards the link posted above - I note they state that the EU Urban Cycle is a simulation of driving around Los Angeles - this is an oft-repeated myth. It's not, its different cycle for the EU. All of the cycles are non-representative in that they are run with a static vehcile on a rolling road. They do however give useful comparison figures between vehicles.
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>All of the cycles are non-representative in that they are run with a static vehicle on a rolling road.
That's something that's always puzzled me. Does it mean that the tests take no account of aerodynamic efficiency? I seem to remember when aerodynamics became fashionable in about 1983 (Audi 100, Renault Fuego) that these cars' improved performance in the official 56 mph test was attributed to their streamlined bodywork, but if they weren't actually displacing any air during the test...
Could this be why I always find running outdoors much harder than the equivalent speed on a gym machine? Then I do have rather more frontal area than average!
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@ Woodbines If the car is driven in the same manner as before the MPG will improve having more power will keep the car in a taller gear longer. www.amdtechnik.com/technical.remap.cfm ;O)
That can be true at certain speeds under certain conditions. It cannot be generally true otherwise economy would rise proportionally to engine power. But you are correct in that gearing is important and should be matched to the engines power and torque characteristics.
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some interesting comments their Aprilla- particularly the ones about manufacturers having to cater for a wide range of operating conditions and to fit in with regulations. This is exactly why a remapper who doesn't have these constraints can offer you something 'better'.
Regarding 'throttle openings' I was talking more about the amount you have to push the loud peddle down and the amount of revs needed for a given speed. I don't claim to be a technical expert but I do have experience of remapped cars and given the same driving style they DO give better MPG.
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>I do have experience of remapped cars and given the same driving style they DO give better MPG.
Better in that specific set of conditions, perhaps, because - as you acknowledge - it isn't having to allow for all those other factors Aprilia mentions. Which prompts me to think: I have a £150 digital camera with a set of about eight 'scene modes', which claim to offer optimized exposure selection, colour balance and a variety of other factors for different kinds of subjects and shooting conditions. Why then, and when Land Rover can offer me a dial to tune my 4WD system to match what's underfoot, can I not have a dial on the dashboard or in the engine compartment that selects a map designed for the specific conditions I'm operating in?
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Why then and when Land Rover can offer me a dial to tune my 4WD system to match what's underfoot can I not have a dial on the dashboard or in the engine compartment that selects a map designed for the specific conditions I'm operating in?
I dont think LR would be interested in fitting one but aftermarket ECU's are available which store more than one map and are switchable on the dashboard by the driver: www.emeraldm3d.com/em_k3.html
A bit too complicated for Joe Public?
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It is entirely possible to have more than one map, or better still a map which is continually modified by the ECU in response to the driver's behavious. Mitsubishi did this many years ago (early 1990's) using a software technique employing what is known as 'fuzzy logic'. Similar techniques are also widely used in automatic transmission control - again Mitsubishi pioneered this with their 'INVECS' TCM.
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All cars have more than one 'map' though don't they? A huge range of operating tables for whatever condition the car is running in.
If you mean different boost and ignition timing advance targets independent of whatever map the car is running then it's perfectly possible.
We use REVO software on our MKV Golf with the 2.0T FSI engine and it is possible to use a switch (by this I mean a device you plug into the OBD port which switches between sets of maps) to set these boost and timing targets dependent on what conditions the car is being used in. For example if I was to take the car to a track I would set it to maximum performance based on 98 Ron or higher fuel. In this condition the car has been rolling roaded at 260bhp- some 60bhp more than standard. In everyday use I have it set to a more car friendly 230bhp and if I use the car on a long run I'll 'dumb it down' and set it for 95RON fuel and cruise at 70ish.
Furthermore by using VAG-COM software I can see, in real time, exactly what effects these changes have by monitoring the data from the MAF, boost sensor and the air intake temperature. I can even go so far as to customise different settings for different conditions based on the data from my own car.
It's a remarkable piece of software/hardware that allows you to have a fantastic level of control of the car's performance.
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All cars have more than one 'map' though don't they? A huge range of operating tables for whatever condition the car is running in.
A 'map' is that one big set of tables which covers everything. Typically there will be only two, possibly three; i.e. idle map and off-idle map.
The map itself can be dynamic in that certain coefficients will not be constants, but variables - e.g. long and short-term fuel trim etc etc.
Some remapping companies (e.g. ECUTek) give a facility to switch between the standard and modified map. In the case of ECUTeck, IIRC, they run a wire to your heated rear window switch such that if you hold wide open throttle and push the switch then it changes map.
There is plenty of software about then enables you to play about with the ECU mapping (e.g. see openECU.org) but unless you really know what you are doing there is lots of potential to do damage. In particular,playing about with boost pressures, knock thresholds and AFM scaling can do all sorts of damage over the long term. The Impreza and Evo boys do a lot of remapping and I think there is the odd melted piston or damaged crank as a result.
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and AFM scaling can do all sorts of damage over the long term. The Impreza and Evo boys do a lot of remapping and I think there is the odd melted piston or damaged crank as a result.
My Impreza was Ecutek'd and other than at the point of mapping there was nothing you could do to modify it other than switching it on and off. The beauty of the REVO software for VAG cars is that you have almost infinite control over many parameters. Of course it's possible to cuase damage which is why you look at the data VAG-COM gives you before making rash changes.
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>> If the car is driven in the same manner as before the MPG will improve >> having more power will keep the car in a taller gear longer.
But you are correct in that gearing is important and should be matched to the engines power and torque characteristics.
That is where the mpg improvement comes from; in normal driving you can usually be in a higher gear, and less likely to have to change down for hills or moderate acceleration, than when driving the car unmodified. My tuning box takes less than 5 mins. to fit/ remove so I have driven it standard/ modified in the same day quite a few times.
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Thanks so much to all of you for the VERY detailed response...What a great forum this is, a credit to all who comment.
The response below from Mike Copper at DMS is attached below which seems like a great power uplift for half the MB Dealer aproved price. Will let you all know how I get on....
"We take the TDV6 320CDI to around 280 BHP and increase torque by around 60 lb/ft. It really is a good upgrade and it remains undetectable by Mercedes service and diagnostic equipment. Cost £850+vat and the upgrade can be carried out at your location"
--
\"Eagles may fly in formation but Weasels dont get sucked into jet engines\"
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That suggests it's going to be a generic map but rest assured that DMS do have the experience of many similar cars to base their map on.
If you join a MB forum you may even be able to get a small discount on that price (10% is normal)
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