ECU Remap

Richard53

JustinR1979 wrote: »

Car makers spend billions to make engines efficient, materials light etc for lower emissions and higher mpg.
I don't believe a chap with a laptop writing generic maps can achieve better mpg and better performance at the same time.
I've always equalled the mpg when on a run.

Nodding_Donkey wrote: »

It's because the guy with the laptop doesn't have to make it meet type approval emissions levels at prescribed rpm.

Also, car manufacturers have to design a map that will deliver acceptable performance anywhere the car is sold. In the case of many, that will be world wide - with all the variations in fuel quality and operating conditions that this implies. The factory tune is indeed very clever and well-developed, but it is necessarily an average. If you know the vehicle will always have decent fuel, and not operated (for example) in polar or equatorial temperatures, then you can tweak the map to optimise performance for the conditions it will encounter day to day.


You are improving efficiency, and you can take that as better performance or better economy or, if you are careful, a bit of both.


Also (talking of bikes, may be true of cars), many bikes have a flat spot engineered into the power curve precisely at the revs where the noise tests are specified. They need this to pass Type Approval, but once they are in private ownership you can override the ECU map e.g. with a Power Commander to remove these flat spots completely and let the engine perform how it was designed to. This also seems to give efficiency gains.

JustinR1979

Gloomendoom wrote: »

Generic maps aren't necessarily that bad. After all, that's what manufacturers install at the factory.

indeed, if you get a good one
I've had a couple, neither had any downsides, and mpg stayed the same.
Brothers 330d was mapped to be aggressive as possible, disregarding mpg. It's a bit of an animal.
Reminds me of a cossie how it boosts and you bang through the gears, only much much quicker!

Retrogamer

Benefits of turbo diesel remap

Increased power & torque.
Sometimes increased mpg


Cons of a diesel remap.

Can clog up the EGR / VNT / DPF quicker because of the increase of particulate matter.
Puts more strain on the turbocharger.
Increases intake manifold temps.
Potential MOT issues (depending how aggressive the map is)
Can make the car a lot more smokey from the rear whilst driving.

gilbert_and_sullivan

Hintza, an ex colleague of mine used a 3.1 litre Jeep GC for commercial towing a car trailer, the vehicle, manual, was well up to the task in hand.

Remaps tend to be for increased power, i too have never seen convincing proof of better fuel consumption, any use of the extra power available will negate any improvements.

Is there a specific reason for the remap power wise, or is purely for eceonomy, if its economy only then your right foot, predictive driving, maintaining momentum and maximising overrun will save you more than any remap.

You'll be using the vehicle for heavy towing, the question you have to ask, is the drive train able to take an increase of X% torque at Xrpm under full power, not suggesting you don't know how to drive here but especially with a TC auto, it would be too easy to just floor it pulling away from junctions fully loaded and put goodness knows what strains through the drivetrain, i don't know what torque the system was designed to cope with when made.

If you decide to remap, i would suggest you invest in replacing all transmission oils at the very least.

StrugglingApprentice

Manufacturer maps have to take more into consideration than mapping companies. They have to meet much more stringent regulations than an mot, run on crap fuel available anywhere, be able to cope with poor maintenance ect...basically, they have to fit the lowest common denominator.

Many diesels are deliberatley mapped down to sell more petrol models, too. Why buy a 30mpg petrol when you can get a 50mpg diesel with identical, if not better, performance? The gap on performance is ever closing because of the extra money and research manufacturers put into diesel technology.

A remap can make a car more economical by making it use the power more effectively.

One thing that is altered is timing advance. This increases cylinder pressures, raising heat in the cylinder and igniting the (diesel) fuel more effectively, the downside is wear on engine internals and emissions. It is able to extract more energy from a given volume of fuel. Just one of what can be litterally hundreds of coding modifications.

forgotmyname

Altering the timing increases cylinder pressures? How?

To increase the pressure you need more volume or compress it to a smaller space. So either a bigger bore or a longer stroke and skim the head etc.

Mapped down to sell petrol cars? Performance is closing? How long before they get a 1L diesel engine to produce 138bhp?

Gloomendoom

forgotmyname wrote: »

Altering the timing increases cylinder pressures? How?

To increase the pressure you need more volume or compress it to a smaller space. So either a bigger bore or a longer stroke and skim the head etc.

Mapped down to sell petrol cars? Performance is closing? How long before they get a 1L diesel engine to produce 138bhp?

I assume he was referring to the cylinder pressure generated by the exploding fuel/air mixture. Advancing the timing gives a better burn but higher pressures.

Retrogamer

forgotmyname wrote: »

Altering the timing increases cylinder pressures? How?

To increase the pressure you need more volume or compress it to a smaller space. So either a bigger bore or a longer stroke and skim the head etc.

Not sure about altering the timing, but increasing the boost pressure on the turbocharger cause it to force more pressure into the cylinders. Too high boost on too weak an engine will normally blow a gasket or if engine is really weak bend a conrod.

forgotmyname wrote: »

Mapped down to sell petrol cars? Performance is closing? How long before they get a 1L diesel engine to produce 138bhp?

A 100bhp diesel could out perform a 138bhp petrol engine if it produces more torque.

JustinR1979

Retrogamer wrote: »

A 100bhp diesel could out perform a 138bhp petrol engine if it produces more torque.

Obviously depends on circumstances, but flat out the bhp wins through every time

forgotmyname

Ive compared the MK3 2L petrol Mondeo against the MK3 2L diesel.

142bhp (190Nm) for the petrol, 130bhp (330Nm) for the diesel. Off the line the petrol has the edge then as the diesel turbo spools up it shoots into the lead but more gearchanges are required to keep it there until the petrol car comes past again.

Mid range overtake the diesel is the choice, But limited revs and the petrol is still going in the same gear.

Swings and Roundabouts.