Diesel Chips / Diesel Tuning - How Its Done

[DieselTuner2]

Considering how many threads I end up commenting in regarding diesel chips, performance products, intercoolers and how they work, I thought it might be a good idea to start up one thread, with the intention of separating fact from fiction regarding these topics.


Diesel Performance Chips: 2 Catagories (CR/Pre CR)

First a basic break down of what happens on each piston cycle in a diesel engine.

The engine control unit reads a lot of sensors before it decides when, and how much fuel to inject on each engine cycle.

Crank Angle Sensor: The ECU reads this to determine which piston is next to fire, and how far away it is from its injection point.

Boost Sensor/Manifold Absolute Pressure Sensor (MAP): The ECU reads this to determine how much air pressure is going into the cylinder. The more pressure, the more oxygen that is available to burn the fuel thats injected.
At sea level, the pressure in the engine is 14.7 pounds per square inch (PSI). Anything shown in Gauge pressure, is 14.7psi + boost in PSI.

Air Temperature Sensor: As critical as air pressure. The cooler the incoming air is, the more oxygen that is available to burn the diesel that is injected into the cylinder.
This component of it is as important as air pressure when it comes to engine longevity.

Engine Coolant Temperature: Used as a compensation by the ECU to determine if too much fuel is being injected resulting in very high combustion temperatures.

Exhaust Gas Temperature: Rarely used by OEM ECU as the EGT does not indicate actual combustion temps on modern day diesel engines. Only water temp gives a true reading of actual combustion temps due to post combustion fuel injection that keeps EGT high to help drive the turbocharger exhaust wheel.

Throttle Position Sensor: Is used by the ECU to determine how much torque is being requested by the driver.

Common Rail Pressure Sensor: Measured by the ECU to determine how much pressure the CR pump is delivering.

Now to the Types of chips and how they Deliver.

Common Rail Chips: Comprises of two types of chips (Injector Extender and Pressure Increaser)

Pressure Increaser Chip:
The 'Chip' takes the common rail pressure sensor signal and drops it by X voltage so the engine control unit sees 'low' pressure at the common rail sensor.
The ECU then tries to correct this low voltage by demanding more pressure from the common rail pump.
This increase of common rail fuel pressure pressure increases the amount of diesel each injector fires, thus increasing power with the extra fuel injected.

Injector Extender Chip:
The engine control unit fires the injector when required, the 'Chip' does not allow the ECU to close the injector when it is asked by the ECU. It keeps it open for a few milliseconds longer which allows more fuel to be added per injector fire sequence.
Power is supplied to each injector constantly and the ecu turns the earth on to open the injector and off to close it.

The injector extender chip watches for end of injection point, and maintains the earth contact to keep the injector open.
This type of chip plugs directly into each injector between the ecu plugs and the injector itself. As it is extending only one injector at a time, there is no other way to go about it.

Fuel Pressure Chips: Plug into the Fuel pressure Sensor on the common rail.
Extender Chips: Plug into injectors.
Chips that can adjust injection timing: Plug into the crank angle sensor.
Chips that can adjust Boost: Plug into the MAP (Manifold Absolute Pressure) Sensor.
Chips that can control Everything in one: Plug into the main ECU harness

CANBUS Explained:
What is CANBUS: Controller Area Network is what it stands for.
It basically means every sensor can be connected to the same wire, and each sensor has its own address. So commands issued by the ecu are headed with a certain address and each sensor will only respond to the signals with its address tagged onto it.

Four wires are normally used on a CANBUS system. CAN-HI and CAN-LOW, V+ & V-
CAN-HI is used for systems such as airbags, abs and other critical systems. The CAN HI signal will always be dealt with first by the ecu as they are more important
CAN-LOW is used for systems such as indicators, lights, seat warmers etc.. Non Critical systems.

There is often many seperate CANBUS circuits through out the car. Engine Control / Gearbox Control / SRS Controls / Lighting etc..

A sudden surge of companies are pushing this so called 'New Technology' onto customers. Calling their chip's CANBUS controllers or the likes, claiming only 3-5 wires are necessary to control ever engine function under the sun.

As far as I know, no Common Rail diesel vehicles are sold in Australia that use a CANBUS system for engine control at all. Even the VW Toureg TTV10 does not use it for engine control! I cannot think of a more technologically advanced Diesel 4x4 in the country.

Each control system has its own dedicated circuit/wiring back to the ecu. This includes Fuel Pressure > Boost > Engine RPM > Throttle Position > And everything else needed to run the engine.

The only few engines I know of that do run any CANBUS system is some older VP44 Pump equipped cars such as the early 3.0L Patrol and Holden Rodeo.

And the only CANBUS system used on these is pump control.

If anyone is trying to sell you a 'CANBUS Chip' or pushes this kind of technology in their advertising, I urge you to bring it to the public's attention - such as raising it in a public forum where you may get proper advice and avoid wasting your money.

If what they are selling is indeed misleading and false, name and shame them. If members dont do this, companies continue to make money off abusing peoples trust.

Each type of chip has pros and cons.

Pressure Chip Pros:
More pressure = better atomisation of the fuel. The finer the droplets of fuel are, the easier they mix with oxygen molecules, which helps the fuel to burn more completely.

Pressure Chip Cons:
Lets say the ECU is demanding 25,000 psi and getting a feedback reading of 20,000 psi it will eventually pick up that something is wrong and put the car into limp-home mode.
Generally it detects a fuel leak, as its demanded pressure is much higher than actual pressure. This limits this type of chip to how far the factory sets its 'fail safe defaults' outside of the operating range.

It also poses a problem of putting the common rail system past its maximum safe working load.
Most systems will cope with 24,000-28,000psi constantly. It is very common for chips to have the systems working at or past their recommended limit. The risks to this are, common rail splitting/breaking, injectors splitting/leaking, or injection lines starting to leak from their joints.

Injection Chip Pro's:
Is undetectable by the ECU as it is holding the injector open after the ECU demands a close point. The ECU cannot measure if the injector is open or closed! It relies on the fact that the injector is doing what the ECU is demanding of it.

Injection Chip Cons:
The longer the injector stays open, the lower the fuel pressure behind it will be.
Lower injection pressure generally results in less atomisation of the fuel, which will not mix as easily with the oxygen and thus will not burn as easily.

Spill Valve Timing / Pre CR Chips: Clearing up the big myth.

What is a spill valve?
It allows more or less fuel to pass through the injector pump. Effectively giving us electronic control over how much fuel is injected.

Just as with our CR injector chips. A spill valve chip, will allow us to hold the valve open longer than the ecu is allowing, by supplying an earth source to the valve after the ecu has turned it off.

When people talk about spill valve timing, alot of them confuse this with actual injection timing.

Spill valve timing relates to how long the valve is held open. The longer it is open for the more fuel that will be allowed to pass.

These types of pumps run an advance slide that is also controlled electronically. This is what moves the actual injection timing of the pump. Not the spill valve.

Air Before Fuel Philosophy:
To burn any type of fuel, oxygen is required. More oxygen content gives us a couple of options.

1) The ability to burn more fuel.
2) The ability to burn the fuel we already have more completely.

They sound similar, but in actual fact are vastly different in a diesel engine.

Completing #1 will always result in more power from a diesel engine. More fuel will almost always results in more power.

The way a diesel molecule burns is like peeling an onion, it continues to burn, layer after layer. Which always keeps the temperature and pressure in the cylinder high (more power).
The main problem is the longer it burns for, the higher your engine/cylinder temperatures will be (resulting in engine damage from excess heat)

 

[DieselTuner2]

Completing #2 will always result in a more efficient engine (not more immediate torque, but more economy and more potential torque). Extracting more energy out of the resource that is already there.
As it burns very quickly when mixed with the right ratio of fuel vs air, the peak cylinder temp will be as high as in an over fuelled engine, but for nowhere near as long (much better for engine longevity).



Injection Timing and How it effects Power/Torque and Economy:

Many chips these days claim to do injection timing. Most of them through sheer ignorance or lack of knowledge confuse injection open time (injector extender) with actual injector opening time.

Sounds very similar again, but is vastly different.

The ECU reads the Crank Angle Sensor to determine which piston is next in line for an injection event, and how far away it is.
It then looks up the tables that have been input into the ECU that determine at exactly what crank angle it needs to fire that cylinder.
It then looks up its compensation tables (air temp/Air flow meter/engine speed/boost/throttle postion etc....) and adds or subtracts this from its normal figure.

Once fuel is injected into the engine, it then takes a certain amount of time once ignited to expand and start doing useful work on the piston to generate torque.

The point of peak leverage that the piston and rod can put on the crankshaft happens to be about 20degrees after the piston has passed its highest point (TDC)

If we inject the fuel when the piston is at 20deg ATDC, by the time it expands the piston will be past the highest leverage point, resulting in low torque production.

So what we need to do is inject it well before 20deg ATDC to ensure the peak pressure is occurring at exactly the right moment.

If we inject the fuel to early though, the pressure buildup will actually be placing negative power down on the piston as it is trying to rise (Delta N is the negative power, Delta P is positive power) and peak cylinder pressures will be vastly higher putting alot of strain on all the engine components.

Some Delta N is always going to be there, but when the timing is set right, the small amount lost to Delta N will be well and truly overcome by greater Delta P

To throw another spanner in the works, the amount of time in milliseconds it takes for the flame front to expand depends on such things as boost pressure and air temperature.
The more tightly packed the oxygen and fuel is in the cylinder, the faster it will burn.

At low engine speeds the piston is moving up and down relatively slowly, so the timing doesnt have to be very fast to ensure PCP (peak cylinder pressure) is reached at 20deg ATDC.

However at higher engine speeds, the piston is moving much faster. We have to inject the fuel earlier to ensure PCP occurs at 20deg ATDC.

So as you can see, timing is in my opinion the most critical aspect when tuning any engine.
If it is set wrong, the engine will either make little torque or possibly be damaged through excessive cylinder pressure.

Factory injection timing is NEVER right. It is tuned not for peak torque or peak engine efficiency or maximum engine longevity.
The ONLY factor that matters to the OEM is Engine Exhaust Emissions! Cleanest emission timing is worlds apart from Efficiency/Torque/Longevity.
2 Degrees of crankshaft rotation earlier injection timing is all it takes sometimes! It sounds insignificant, but this can produce an 8-10kw at the wheels gain in power with no additional fuel or boost. However emissions will suffer greatly for this which is why OEM do not make it perfect for Power/Efficiency.


Intercoolers:

There are two main factors in what makes an intercooler work effectively.

1) Pressure Drop
2) Heat Rejection

#1 is exactly as it sounds. If you put 13psi into the intercooler and receive 10psi out of it.
You have a 3psi pressure drop across the intercooler.
Clearly the lower this drop is, the better the intercooler is allowing the air to flow through it.

Somewhere between .5psi and 1psi is a good level of drop to have. With zero drop at all, the intercooler probably doesnt have enough internal surface area to cool the air passing through it effectively.

#2:

How much heat can the intercooler pull out of the air and how fast can the intercooler pull it out.

Think of dissolving aspirin in a glass of water. Drop the whole tablet in it and it will take 2-3mins to dissolve completely. The surface are of the aspirin tablet we will say is 3cm2 (the whole outside of it)


Crush the aspirin tablet up to a powder, drop it in and watch it dissolve in a matter of seconds.

What we have effectively done is increase the surface are of it to say 30cm2. By having smaller pieces, more of it is in contact with the water at the same time allowing better mixing.

Same rule applies with intercooling. Having fins or turbulators inside the tube allows alot more of the air inside to be in contact with the intercooler at the same time vastly reducing the time taken to cool, and allowing more cooling to be done for a given size intercooler.

Hot Air vs Cold Air vs Pressure

The cooler air is, the more oxygen content is available in a given amount of it.
The more pressure the air is under, the more oxygen content is available in a given amount of it.

So it is easy to see, there are two effective ways of increasing our engines supply of fresh oxygen (Things such as exhaust flow, intake manifold flow and so on. Do play a big part in it also, but to keep it simple we will talk only about pressure and temp in this section)

Compress the air futher through more boost.
Or
Cool the air down more with an intercooler.

More boost will generally give the highest level of oxygen available in an engine. The drawback to it is more boost means higher cylinder pressure.

And without an effective way of measuring actual cylinder pressure after the boost has been added and compressed further by the piston, we have no way of knowing how close it is to the maximum safe working pressure each engine was designed for!
Diesel engines are built very strong. It is hard to kill one with boost alone, but the main thing that is effected is headgasket sealing.

The turbocharger is also placed under alot more stress, again what is its maximum working level?

The only way of knowing is through mathematical calculations. But even once you have this data, try and ask the manufacturer what its max working level is? You wont get an answer.

Intercooling then becomes a much safer option for all the components involved.
1) The turbocharger isnt working any harder.
2) The engine isnt under any more strain (actually less).
3) The cooling system isnt having to deal with the increased temp's.

The best advice I can give to people, is to be modest when playing around with boost levels.
Somewhere around 10-20% increase would be an acceptable level depending on how much boost the car runs standard.
Talking standard setups here to. Not aftermarket turbo's etc...
If it is 10psi, you would look at an increase of about 3-4psi (applicable with older indirect engines and non VNT turbo's)
If it is 25psi, you would look at an increase of maybe 1-3psi (newer DI/CRD engines with VNT)

No turbocharger is built for OEM cars with a 30-50+% overhead in safety margin. Lifting it to these kind of levels will result in turbo failure well before normal running conditions would kill it.

As the boost is increased, the temperature of the air coming out of it increases also.
Think bicycle pump and how hot it gets after pumping a tyre up.

The average charge air temp of newer CRD engines running around 20psi is 160-170deg celcius.
Most standard intercoolers will knock 100deg off this, which is considerable.
What we really want though, is to get that air as close as possible to ambient temperature.

Dropping the air from 70deg down to 30deg will give us nearly equivalent oxygen to another 1psi of boost in the cylinder.


Exhaust Systems:

How Exhaust Gas Flows best! - The hotter the gas is, the faster it will flow through pipework.
Hot gas is much less dense than colder gas and takes up alot more space inside the pipework.

It is important to keep this gas speed as high as possible, through proper exhaust size selection. The faster it is able to escape the exhaust system, the less work the engine has to do to pump it out.

Based on these facts, the perfect exhaust will start off large because the gas takes up a considerable amount of 'space' when it is hot, and will effectively shrink as it cools and passes through the exhaust. So dropping the size down towards the back promotes high flow.

If the exhaust sizing is to big, the gas will try and expand to fill it. This expansion is counter productive. You want the exhaust gas to be spending all of its available energy to get through the pipework, not expanding to fill it.

This has been proven many times and is used extensively in petrol race cars searching for every bit of 'free power' they can get.

Types of Turbo's and how they effect Exhaust Selection:

Wastegated Turbo's: In a wastegated turbo, a certain percentage of the exhaust gas will bypass the main turbine wheel to limit how fast it spins (reducing or limiting boost pressure)

It is imperative that a large open dump pipe be used in this system to promote mixing of wastegate gas, and turbine gas.
As most wastegates open, it blows directly into the path of the turbine flow. Resulting in turbulent gas that will not flow readily in the one direction it is being sent.

 

[DieselTuner2]

If you open the dump pipe up, it helps get this turbulent gas mixed, and flowing well down the rest of the exhaust system.

If you have a very narrow or small dump pipe, the gas will continue to be turbulent and continue mixing much further down the system. Lowering overall flow.

The ideal solution to this is to have a divider in the dump pipe that straightens the wastegate gas out, and points it in the right direction before it has to start the mixing process.

Some people play around with divorced dump pipes. The problem with this is, it really limits the size of the pipe you can use for either/or.

Off boost you want as much flow as possible for the main turbine, and on boost you need alot more for the wastegate. So limiting your pipe size one way or the other will only benefit one condition (more flow on boost or more flow off boost). This is why large bell mouth dump pipes work the best under all conditions.

VNT/Variable Vane Turbo/Variable Geometry Turbo:
The boost control of these turbo's is achieved effectively by making the rear housing of the turbo smaller through the use of 'vanes' (small flat pieces of steel) to spool the turbo.
Once these 'vanes' are open the turbo will behave like it has a large rear housing that will flow very well.

It is important to note, as no wastegate gases need to be mixed in the dump pipe. It can effectively be made much smaller than a wastegated turbocharger.

EGR: How it works, What it does, What are the drawbacks to it for the end user.

EGR is designed for one purpose, to reduce the amount of NoX or Oxides of Nitrogen produced by the combustion process.
Two main factors contribute to NoX generation.

Temperature and Pressure.

By passing burnt exhaust gas back into the intake system, we reduce the amount of fresh air available for the fuel to mix and burn with. This reduces how much temperature is generated through each combustion cycle.

By rights, this does not pose any kind of problem apart from reduced torque.
So by removing this system, you generally will notice a small improvement in economy and power. But, the EGR system is only operating at idle and light cruise conditions. So high load engine running is completely unaffected.

The problem arises from the engine breather system which is recirculating blow by or oil vapour back into the intake system also.

Once these two mix (Exhaust gas and Oil) it forms a horrible paste that resembles vegemite and builds up on the internal walls of the intake manifold and head ports.

Once there is a coating on the manifold, it provides a nice sticky surface for more EGR build to stick to also. Snowball effect.

The more buildup that is stuck to the manifold and head ports the smaller the ports become.
Smaller ports do not flow as much air as larger ports obviously.

Over time, this significantly reduces the amount of airflow through the engine. The boost level will remain the same however (remember Pressure and Flow are two different characteristics of an engine)

On All older diesel engines without electronic control, the injector pump will continue to inject the same quantity of fuel regardless. It has no idea the engine is down on airflow.

On most newer DI/CRD engines, the Air flow meter is referenced but this does not always mean the fuel system will deliver less fuel with the reduced flow. Often it is simply throttle position and boost that is used to determine how much fuel is being injected.

With less oxygen in the cylinders, the same amount of fuel will not burn as efficiently and it will continue to burn for longer through the power stroke. Significantly increasing EGT, and lowering the potential efficiency and torque output of the engine.

There are two way's around this dilemma.
1) Remove the EGR system early on in the picture so it cant cause these problems.
2) Use a good quality engine de carboniser at regular periods (every service)
Some cars are seriously effected by the removal or blanking of the EGR system, thus option two is the only way to go on these vehicles at the moment.

Dangers and Limitations:

Diesel tuning is very dangerous to amateurs. As more fuel almost always results in more power, some people can get carried away with it.

Unless you have the proper equipment (boost gauge and EGT minimum) I would strongly urge you to either leave your chip on a minimal gain setting, or have it setup by someone with the proper test equipment.

Fuel Rail Shimming:
One end of the common rail houses a pressure sensor, the other end always houses a pressure relief valve. This is simply a ball and spring setup on most vehicles.
It is possible to place a small shim underneath this spring which will effectively increase the amount of tension the valve is placed under.
The higher the tension, the more fuel pressure that is required to lift the valve off its seat.

It is there in the event of an engine control mishap causing excessive pressure in your common rail.

Each manufacturer destroys many systems to find the absolute pressure limits.
Some manufacturers relieve the fuel pressure well before this max limit, other relieve much closer to it.

There is a couple of vehicles that can be shimmed and kept under their maximum working pressure,
And
There is lots of vehicles that cannot be shimmed even slightly without lifting the pressure past the limit.

Im not going to say which is which so please dont ask.

Just be advised that performing this modification on some engines can result in fuel system damage. Your dealer can send the broken parts for analysis and it will clearly show overpressure has caused the problem and they will not warrant the repairs.

 

[DieselTuner2]

Brands Explained - Who does what and how they do it.

With so many 'Chip' manufacturers out there these days it can be very confusing for anybody thats looking to buy one.

It has also become common place for retailers and manufacturers to lie about products, place false advertising on web sites and generally try to win their way to the sale through misleading statements and comments. All this thread is aimed at doing is arming its users with basic knowledge of how everything works to give them some idea if what they are being told is truthful or not.

Most chips will just give you more fuel in a very crude fashion.
Add electrical resistance to certain engine control sensors to achieve the desired result.

Some chips are smarter than others in how they go about delivering extra fuel.

Other chips have additional features such as EGT Control, Boost Control and Injection Timing control.

It is easy enough to make your own crude fuel control chip with nothing but a few variable resistor pots that you can buy from jaycar. Include a little plastic or aluminium case and your looking at about $30 worth of bits if you have the knowledge to put it together.

It wont have any of the features that more expensive chips do, but it will be exactly like most of the very cheap options out there (such as low cost ebay chips)

Almost every chip made is able to be adjusted by the end user. This is great for the people that do know there are limits when tuning a diesel, but can be disastrous for people that think the worst thing that happens when you turn the fuel up is smoke comes out the back. One main thing to notice is some of the worlds biggest manufacturers of diesel chips is they have modest power gains compared to some others. This is not because they are low quality, it is because they have put significant research into what is a safe level on each vehicle for maximum longevity of the engine, Meaning less warranty claims for them.

Alot of chip manufactures out there share technology as it is much cheaper for them to buy certain aspects of the chip that other company's produce than completely design them from scratch.

An even larger amount of companies (Mainly Retail shops) simply buy in bulk off a manufacturer and re badge the chip for their company.

Now, there is nothing wrong with doing either of those two things. The only thing I would consider wrong is if a company lies about producing a product that is completely their own.
They have every right to refuse to tell customers or anybody that ask's, who actually makes their chip. But they have no right to claim it if they did not design and produce it.

I would say it is fair to say "it is made overseas for us", or "by another company for us"

How the tuning is done:
As mentioned above the Factory ECU uses many inputs to decide when and how much fuel to inject, as well as how much boost to run.

Chips generally use one of two inputs for tuning. Common Rail pressure & Injector Signal.

1) It references its stored figures and determines at what pressure the engine is running, and how much voltage it is being demanded to pull out of that signal.

2) Or it reads that the injector is closing and must be held open slightly longer.

Some of the more advanced chips run multiple inputs to determine what needs to be done.

This is known as 2D and 3D mapping.


2D uses just one input (weather its fuel pressure or throttle position or injector signal or boost etc..)
3D uses an RPM signal from the engine, as well as a load reference input.

The big benefit to 3D mapping is it gives the tuner much better control over what rpm the additional fueling is given and how much more based on the drivers input (throttle position is generally the best one to use) This is exactly why the factory computer uses 3D mapping.

We may want to leave the low rpm (1000-2000rpm) and less than 20% throttle alone as generally no more power is required at this level, but then increase the fueling above 2000rpm even if it is still less than 20% throttle.

This is something that cannot be achieved with a simple 2D mapping chip.

However, this is NOT to say 2D mapping chips are hopeless! They are still adjusting ontop of the 3D map made by the factory ecu. They just dont have as much flexibility when setting them up.

Companies:
CRD Only. Below is from my knowledge of the chips I have used. I wont speculate on any that I have not, so there will be a few brands that are not in this... Yet.
Some of what is below may be inaccurate and I am more than happy to change any details upon request if anybody points out something I have missed from a product line up, or something that is inaccurate.
I cant keep up with every manufacturer every day of the week, so please refrain from becoming angry if I have made an error. Simply report it and I will amend.

With some companies, im not sure weather they are resellers or produce a product that closely resembles another companies product.

DTE / ChipTuning - Manufacturer
http://www.dte-diesel-tuning.com/

Type of Fuel Adjustment: Fuel Pressure And/or Injector Extend
Boost Control:Optional on some chips
Timing Control: NO
Mapping Type: 2D & 3D Optional
Safety Backdown: NO
Sensor Pickups: Fuel Pressure/Crank Angle Sensor (option for 3d Mapping) MAP Sensor (optional for boost control on some chips)
Self Install: YES
Map Switching: Only via chip under bonnet

Tuneit - Manufacturer
Performance & Economy Diesel Tuning by Tunit - Work, Play & Save

Type of Fuel Adjustment: Fuel Pressure Only
Boost Control: NO
Timing Control: NO
Mapping Type: 2D
Safety Backdown: NO
Sensor Pickups: Fuel Pressure
Self Install: YES
Map Switching: Only from chip under bonnet

Steinbauer - Manufacturer
STEINBAUER Tuning Technologies

Type of Fuel Adjustment: Injector Extend Only
Boost Control: NO
Timing Control: NO
Mapping Type: 2D
Safety Backdown: NO
Sensor Pickups: TPS (to turn the chip on and off depending on throttle position)
Self Install: YES - Requires wire to be soldered onto TPS loom though.
Map Switching: optional Incab on/off switch, and option of bluetooth wireless on/off switch.

Unichip - Manufacturer
Vehicle Fine-Tune | Car Performance Chips | Unichip Home

Type of Fuel Adjustment: Fuel Pressure and Injector Extend (optional)
Boost Control: YES
Timing Control: YES
Mapping Type: 3D
Safety Backdown: Water Temp, Air Temp, (Optional) EGT Temp
Sensor Pickups: All Main Engine Sensors
Self Install: Optional PNP Harness or Hard Wired by Dealer
Map Switching: In cab with 5 maps available

 

[DieselTuner2]

Chipit - Manufacturer
Works With ANY Diesel Engine.*|*50% More Power To Your Diesel Engine!

Type of Fuel Adjustment: Fuel Pressure Only
Boost Control: YES
Timing Control: NO
Mapping Type: 2D
Safety Backdown: Yes optional EGT backdown
Sensor Pickups: MAP Sensor and Fuel Pressure
Self Install: YES
Map Switching: In cabin switch, Laptop adjustable and from under bonnet.

ChipExpress Reseller of DTE
Diesel Tuning with CHIP Express™

Type of Fuel Adjustment: Fuel Pressure Only
Boost Control: NO
Timing Control: NO
Mapping Type: 2D
Safety Backdown: NO
Sensor Pickups: Fuel Pressure
Self Install: YES
Map Switching: Only from chip under bonnet

DP Chip - Reseller of Tuneit and DTE
DPChip products list. All about our amazing diesel performance module, specifications and applications.

Type of Fuel Adjustment: Fuel Pressure Only
Boost Control: NO
Timing Control: NO
Mapping Type: 2D
Safety Backdown: NO
Sensor Pickups: Fuel Pressure
Self Install: YES
Map Switching: Only from chip under bonnet

Roo Systems -Refuses to provide any factual information on their product to be posted here.


Type of Fuel Adjustment:
Boost Control:
Timing Control:
Mapping Type:
Safety Backdown:
Sensor Pickups:
Self Install:
Map Switching:

Supercar Performance (Diesel Smart Module) - Unknown Reseller/Manufacturer status (requires more research)

Type of Fuel Adjustment: Fuel Pressure And Injector Extend
Boost Control: Yes (Optional)
Timing Control: NO
Mapping Type: 2D
Safety Backdown: Yes EGT (Optional)
Sensor Pickups: MAP/Fuel Pressure
Self Install: YES
Map Switching: Only from chip under bonnet

How Do These Manufacturers and Resellers Tune Their Products?

Very hard question to answer, and there are many ways it is done!

Most manufacturers use a dyno for this and measure many aspects of the engine running before settling on a final fueling figure that is both desirable to the customer and sustainable for the company to offer engine warranties etc..

The general test equipment used is Fuel Pressure, Engine Water Temp, Exhaust Gas Temp, Boost And Air Fuel Ratio.

It is important to realise that most local resellers or distributors will use just one factor if your lucky when they set your chip up on a dyno for you (over the factory tunes), this one factor is Engine Horsepower. Very few read any other engine running condition apart from this.

It is just so easy these days to look at Dyno graph figures that are pumped out by so many shops and be AMAZED at how much more power they can make!

Dont be fooled, more power doesnt always mean a better tune, it doesnt mean their product is superior, nor does it mean you will get better economy.

It normally just means for a given vehicle, they are pumping more fuel into it (if the rest of the setup is the same ie, exhaust, intercooler boost level etc..)
The downsides to this is reduced engine longevity, more smoke and worse economy.

If you are actually paying a shop to set a car up for you and tune the chip they have provided or one you have supplied.

The things you should be DEMANDING on the dyno graphs upon picking the vehicle up is,

Engine Horsepower/KW
Engine Torque
Boost Level
Air Fuel Ratio

Obviously in a Before and After comparison of those things!

Air Fuel Ratio - How it works
Without going into the science of it, I will attempt to explain in very simple terms how it works. Each car is different so I will be using average figures when I talk figures later on.

AFR is Directly Proportional to EGT

Air is measured in weight (yes it weighs something ) generally measured in grams.
Fuel measured in volume, in millilitres.

If you have 1 gram of air and 1 millilitre of fuel to mix with it, your air fuel ratio is 1:1

The higher this ratio in a diesel, the cooler the engine will run! Exact opposite to petrol tuning which most people are more used to working with.

At idle and very light running on a diesel it is common for them to run 36:1 all the way up to 75:1 Extremely lean resulting in fantastic economy (turbo petrols will run no leaner than 17:1 without starting to misfire at cruise/idle and no leaner than 12.5:1 under full load without starting to do damage)

Under high load conditions, most standard diesels will run between 20:1 and 24:1 fuel ratio.
(Navara's are an exception being at 18-19:1 from factory, very rich)

Most Chipped diesels will have this fuel ratio at 16-17:1 down from 20-24:1 (and even richer on a navara)
Thats alot of extra fuel, which does give you more power just as they say.
Remember these companies have to honour their +25-35% increase advertising.
But a proportional increase in EGT also which can reduce engine life.

How do we fix that then? As I have explained earlier, you want to burn more diesel but do it efficiently? Increase the amount of air, or cool the air you have down further to allow more oxygen to burn it.

This is why upping the boost (within reason), increasing intercooler efficiency, adding a free flowing exhaust, fitting a free flow intake filter etc.. are absolutely essential if you want to do it the safe way, not the cheap way.

So from now on!

Start Demanding to see Air Fuel Ratio, Boost, Power and Torque graphs that are overlayed ontop of the standard graphs so YOU can compare and see EXACTLY what has been done to your fuel system to achieve the results. I Personally would absolutely love members to post just this kind of thing up in this thread If they have these results to show with their EFI DI and CRD engines standard, and chipped back to back

 

[Bryce]

Nice write up mate. Lots of myth busting facts there and should be read by everyone looking at a chip

Sent from my GT-I9000 using Forum Runner

 

[kempseyken]

Great read , thanks for posting Northside

 

[ryandm]

exellent post!!

 

[joshman]

As for roo systems... I thought they're just a rebadged DPchip?

 

[DieselTuner2]

...

 

[joshman]

Yeah, I've got nothing against rebadging of chips, nothing at all. It's smart business. People would be surprised at what's rebadged and how little true R&D and manufacturers there actually are. Everything from simple hand tools to white goods, and a lot of auto bits and pieces.

Either way, excellent write-up mate, clears up ALOT of myths and lays it all out. Thanks for the time and effort!

One thing which wasn't quite clear was the difference in available tuning options between the DI ZD30 and the CR yd25 engines?

Being a navara forum, can you extrapolate using these kinds of examples?

 

[user 10312]

Nice write-up mate. Well done!

 

[DieselTuner2]

...

 

[tweak'e]

question for ya..... AFR, what gauge/sensor do you need to measure it and do they last very long on a diesel ?
any problems or catches when using them.
just thinking about the DIY guys who do not have access to dyno etc.

 

[DieselTuner2]

...

 

[tweak'e]

just thinking...... auberins egt gauge can be programmed for LC-1 Wideband Oxygen Sensor. good think about the gauge is it has recall of min/max.

 

[DieselTuner2]

...

 

[Dave]

Any updates Lyndsay ?

 

[razzy]

This is simply a great thread, and I for one, appreciate how much time and thought you must have put into it.
My query though, is that I understand that your assessments of the various chips are for CRD diesels only. In my case I have a D22 ZD30 with a tunit chip, a 2 3/4" exhaust, EGR blank and oil catch can. The Tunit unit is currently on the #6 setting (it is the 2005 model). I am presently installing a EGT gauge.
The main reason for these changes is to increase efficiency and realiability when towing the caravan. While performance has certainly improved,
I would appreciate your views on this tunit system and how you think it should be "set up", or whether you would recommend an alternative.

 

[Navvic]

Nice write up bud. Thanks.