Why don't manufacturers "Map" their engines
Discussion
They do, but the maps are focussed on economy and emissions. The engine will also have to work in a variety of different climates and areas around the world with differing fuel qualities. The standard maps are a balance to keep the engines eco friendly, economical and make sure they will provide the same power output no matter where they are used.
Every (ECU-controlled) engine has a map. Otherwise it wouldn't run.
A manufacturer has a great deal of issues to take into consideration when mapping their cars, as most cars are now "world" cars.
Firstly, emissions, that affects the up-front and ongoing costs to the customer, so affects the sale chances. Then will the car start and run fine at -15 in Canada, or +40 in southern Italy? The car has to be driveaable by the most ham-fisted individuals and work with the other in-vehicle controls...
When you re-map your car, it only has to please one individual and work under a much narrower band of parameters.
A manufacturer has a great deal of issues to take into consideration when mapping their cars, as most cars are now "world" cars.
Firstly, emissions, that affects the up-front and ongoing costs to the customer, so affects the sale chances. Then will the car start and run fine at -15 in Canada, or +40 in southern Italy? The car has to be driveaable by the most ham-fisted individuals and work with the other in-vehicle controls...
When you re-map your car, it only has to please one individual and work under a much narrower band of parameters.
You are missing something.
Manufacturers do 'map' their cars but, they do so with certain tolerances. Many remaps will be likely to increase general wear on mechanical components which, could become expensive if you are the manufacturer and have a warranty to honour.
They may also have other reasons for not mapping engines to their full potential, for example, they may wish to give a particular model x amount of peak power in order to place it at a certain point in their model range or pit it against a particular competitors car.
Manufacturers do 'map' their cars but, they do so with certain tolerances. Many remaps will be likely to increase general wear on mechanical components which, could become expensive if you are the manufacturer and have a warranty to honour.
They may also have other reasons for not mapping engines to their full potential, for example, they may wish to give a particular model x amount of peak power in order to place it at a certain point in their model range or pit it against a particular competitors car.
As above really, manufacturers have more concerns than just performance - they have to meet stringent emissions and noise regulations in many different countries; support lower octane fuel than the worst you can get in the UK; deal with nd extremes of temperature and altitude that we don't get in the UK;...
They also have much more concern for reliability than the average buyer. If a more aggressive map makes a car 0.1% more likely to fail, that's pretty insignificant to the average owner but can make a significant difference to total warranty costs over the millions of cars that a manufacturer might sell.
They also have much more concern for reliability than the average buyer. If a more aggressive map makes a car 0.1% more likely to fail, that's pretty insignificant to the average owner but can make a significant difference to total warranty costs over the millions of cars that a manufacturer might sell.
Edited by kambites on Wednesday 21st August 19:29
I don't believe the "increase power and fuel economy" claims from remaps either. You can't do both and if it was that easy then the manufacturers would do it. Well maybe remaps could do it a bit by going closer to a 14:1 air:fuel mixture but at the expense of higher engine temperatures.
I've yet to see any reports from people who sound like they know what they are talking about where it goes on a dyno AND they measure fuel consumption.
I've yet to see any reports from people who sound like they know what they are talking about where it goes on a dyno AND they measure fuel consumption.
I do bit of work with remaps.
IME you can get an improvement in both economy and power out of the car, BUT NOT at the same time. If you consistently use the extra power, you will use more fuel, despite what the computer readout says. However, if you drive pretty normally, you will usually use less fuel. (a few % less).
IME you can get an improvement in both economy and power out of the car, BUT NOT at the same time. If you consistently use the extra power, you will use more fuel, despite what the computer readout says. However, if you drive pretty normally, you will usually use less fuel. (a few % less).
Also in case of VW etc... they map the cars so the VW is not quicker than a more expensive model
Take the mk5 edition 30 GTI exactly same engine that is in the Audi S3 running 265bhp in the Edition 30 it was tunned to 230 most likely due to the fact that otherwise it would be quicker than the R32!
Also in the case of the 150bhp and 180bhp Golf Mk4 they can charge you a lot more for a standard remap by having the two "different" models
Then of course they is all the other valid reasons above
Take the mk5 edition 30 GTI exactly same engine that is in the Audi S3 running 265bhp in the Edition 30 it was tunned to 230 most likely due to the fact that otherwise it would be quicker than the R32!
Also in the case of the 150bhp and 180bhp Golf Mk4 they can charge you a lot more for a standard remap by having the two "different" models
Then of course they is all the other valid reasons above
All manufactures will 'map' or 'calibrate' their engines. As has already been said, these are a balance of many thing which include emissions, driveability, knock control, misfire, stability, nvh, durability. All these factors have to be checked at varying temperatures and climate at different altitude with many noise factors. This is will inevitably mean you can't run it how a typical aftermarket tuner would see as optimal in terms of power etc.
You won't see aftermarket tuners taking their car to altitude to check that it starts at 6000ft at -7degC.
There is always room for more in the manufacturers calibration. This is when you'll see the R or Rs version with a bit more torque and power etc. This kind of calibration will under go some testing but much will be carry over from the base version. Easy money really.
You won't see aftermarket tuners taking their car to altitude to check that it starts at 6000ft at -7degC.
There is always room for more in the manufacturers calibration. This is when you'll see the R or Rs version with a bit more torque and power etc. This kind of calibration will under go some testing but much will be carry over from the base version. Easy money really.
creampuff said:
I don't believe the "increase power and fuel economy" claims from remaps either. You can't do both and if it was that easy then the manufacturers would do it. Well maybe remaps could do it a bit by going closer to a 14:1 air:fuel mixture but at the expense of higher engine temperatures.
I've yet to see any reports from people who sound like they know what they are talking about where it goes on a dyno AND they measure fuel consumption.
Maybe you can't get an overall average increase in economy and power together. But you can certainly map a car so that under normal throttle you get more economy and less power (for example on a commute where you don't really need extra power), but under full throttle it can be mapped to sacrifice economy for more power.I've yet to see any reports from people who sound like they know what they are talking about where it goes on a dyno AND they measure fuel consumption.
So you get better than standard economy when you want it, and lots more power when you want it as well.
creampuff said:
I don't believe the "increase power and fuel economy" claims from remaps either. You can't do both and if it was that easy then the manufacturers would do it. Well maybe remaps could do it a bit by going closer to a 14:1 air:fuel mixture but at the expense of higher engine temperatures.
I've yet to see any reports from people who sound like they know what they are talking about where it goes on a dyno AND they measure fuel consumption.
I think for diesel, you may be able to boost the turbo pressure, get more air in there and burn the same amount of fuel more completely, giving you a little more power, perhaps you could have bits of the map where you can burn less fuel for same power. However, the issue the manufacturer would have to take into account there is that the more complete burn is hotter (plus higher boost pressure will give some higher cylinder pressures, but diesels are sturdy). this may reduce PM emissions, but it will increase NOX emissions, the two emissions islands that manufacturers have to navigate around, which basically oppose each other. Decrease one, increase the other.I've yet to see any reports from people who sound like they know what they are talking about where it goes on a dyno AND they measure fuel consumption.
On petrol engines.... manufacturers are essentially locked to the 14.7:1 AFR thanks to the catalyst. The 3 way cat works best at this AFR, even a little move either side can kill the effectiveness of one of those catalyst processes. So keeping that in mind, you can't increase air admission without increasing the fuel as well to keep the AFR right.
Max_Torque said:
Funny thing, although load of tuners claim "better fuel economy" not one (as far as i am aware) has had one of their cars tested over the EU std test cycle. Something that costs as little as £1k. Now i wonder why that may be................
I remember an episode of Top Gear where they tried to improve fuel economy on a car with a remap,and it made no difference at all to fuel economy on controlled track conditions.
Max_Torque said:
Funny thing, although load of tuners claim "better fuel economy" not one (as far as i am aware) has had one of their cars tested over the EU std test cycle. Something that costs as little as £1k. Now i wonder why that may be................
But then who would pay to get their car optimised for that cycle, given that they will never actually drive it like that?Gassing Station | General Gassing | Top of Page | What's New | My Stuff