Diesel remaps tech info

obi_waynne

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What exactly are the parameters for a Diesel engine remap?

There is presumably no timing/spark to advance so I'm guessing it is mainly fuel quantity and boost duration/amount.
 

HDi fun

TC ModFather
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637
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Buckinghamshire UK
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Passat 2.0 TDi
What exactly are the parameters for a Diesel engine remap?

There is presumably no timing/spark to advance so I'm guessing it is mainly fuel quantity and boost duration/amount.

That's all there is to play with really. Many tuners will ramp up the fuel rail pressure earlier in the RPM range but still keep peak pressure within the factory defined maximum limits.

Regarding fuelling, they do also play with the injection timing, which is crucial on all diesel engines. All common rail systems use at least two injection phases, a pilot phase to get the fire going and a primary phase which provides the vast majority of the power. It's the pilot phase which gets rid of the characteristic DI diesel rattle and knock.

If you want to hear a noisy DI engine go and listen to a Montego 2.0 Turbo Diesel or a Vauxhall DTi engine. These earlier DI engines for car usage were uncouth compared to the previous generation of IDI engines and as such many people stood aside for obvious reasons. I was one of 'em.

CR diesels do respond very well to remapping, I think many car makers have purposely detuned their diesel engines simply to leave some room in the market for petrol models. During the early part of the 21st Century (first 5-6 years, say) diesel received loads of R&D cash, whilst petrol engines barely evolved at all in that time. Things are back on a more even keel now and we're seeing more and more DI petrol units and some very innovative turbocharging technologies being applied.
 

jarrus

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Suzuki Swift Sport
I suppose the new 3.8 911 turbo is case in point, Direct injected, VVT and Variable vane turbos. I would think that on this car though it employ a wastegate as well else the exhaust back pressure would climb quite high, you could use a bigger VNT but they it would lag more so contradicts the point really...

As Paul said....

Mostly 2 injection phases (not going to repeat what he said) but cars with DPF/FAP technology will also have post injections as well (more injections after the main "power" injection) to control EGT's mainly in the regeneration cycle, on DPF/FAP cars it is crucial to keep the EGT's up so it doesn't clog up as much.

Injection duration also plays it's part and it's how most tuners will increase the fuelling without raising the standard rail pressure, problem is that in some cases the car will smoke a little more off boost.

Also from what I have found the specific ECU used (Bosch EDC15, 16, 17 etc..) makes a difference from a tuners point of view. It seems the later generation ECU's are hard to "hack" but they are the ones that can usually yield the mosts gains due to the fat the the fuel and boost curves can be fine tuned to a greater degree than older generation management systems.

Boost, more boost equals more power? Not really, if you give a diesel engine more air when it's already running clean then it will make less power, fueling is far more important on a diesel than boost to create power, case in point:
Lets take Fiat's 1.9 16v Multijet engine (I believe that is has been recently replaced with a 2.0? cold someone please clearify..) In the Vauxhall astra and the Alfa 159 and various other cars it makes 150 hp and 236 lbft standard, Celtic can extract 212 hp and 327 lbft from using an extra 0.1 bar that's about 1.5 psi of extra boost! so you see, big boost isn't always required. One thing they will do is extend the boost curve so it can maintain it nearer to the redline (on most diesel 4500-5000 rpms, 5k on this engine) On most modern engines manufactures will decrease the boost and fuelling at the top end to force the motorist to change gear earlier to improve emissions and fuel economy and again so they aren't as quick as the petrol cars.
Whilest tuners will exploit the built in "slack" and make it more spritly in the topend of the revband.
 

jarrus

Pro Tuner
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West Midlands, UK
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Suzuki Swift Sport
Also VNT's on diesels don't employ a wastegate,
I would think this is a contrimbuting factor to the fact that these engines are able to produce so much torque.
Food for thought for myself there....
 

tropical

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Cairns-Australia
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Toyota Hiace 3.0D T
Hi guys,
I am interested in ECU remaping or aftermarket ECU to suit my car. I am in Australia so not sure if you have my model but worth a try, I have a 2010 Toyota Hiace SLWB van with a 3.0L turbo intercooled engine with 5 speed man. At the moment it is standard and only puts out 80Kw as compared to the Hilux with the same motor which outs out 123Kw. I want more power and torque as it does not overtake very well and think part of the problem is in the ECU. I believe the engines also have different cams but dont want to do that. Am thinking of 2 1/2" mandral bend hi flow exhaust and watercooled intercooler but not sure what mods will give best value for money. If anyone has info about this engine it would be appreciated.
Shane.
 

obi_waynne

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Hi there and welcome to TorqueCars I hope you enjoy your time here with us.

The Toyota ECU is a real pain to remap as it is locked from the factory. I do not know of any remappers yet who have made inroads into this. The general answer is to add an aftermarket ECU but these tend to be setup for petrol engines.

A piggy back device might be your only answer here. It's is not as good as a remap but some devices are fairly clever and add in to the equation a lot of parameters to play with. Avoid the cheap ebay tuning boxes that just fool the engine into thinking the air is colder than it is.

Try fitting a high flow panel air filter, this will free up the engine quite a bit at the top end and it will feel a little quicker. If you are serious about performance gains then look at uprating the turbo. A different internal set up will change your power band considerably.

Does the intercooler get hot? If it does then look at upgrades but I think your money can be better spent else where for the short term.

The standard exhaust flows very well, in diesel engine speed of exhaust gases is not generally an issue. Particulate filter and the like can restrict power by a few bhp and make sure you use good quality fuel as well.
 

Toggerefc

Wrench Pro
Points
11
Location
Burnley Lancashire UK
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accord2.2ictdi gt
I suppose the new 3.8 911 turbo is case in point, Direct injected, VVT and Variable vane turbos. I would think that on this car though it employ a wastegate as well else the exhaust back pressure would climb quite high, you could use a bigger VNT but they it would lag more so contradicts the point really...

As Paul said....

Mostly 2 injection phases (not going to repeat what he said) but cars with DPF/FAP technology will also have post injections as well (more injections after the main "power" injection) to control EGT's mainly in the regeneration cycle, on DPF/FAP cars it is crucial to keep the EGT's up so it doesn't clog up as much.

Injection duration also plays it's part and it's how most tuners will increase the fuelling without raising the standard rail pressure, problem is that in some cases the car will smoke a little more off boost.

Also from what I have found the specific ECU used (Bosch EDC15, 16, 17 etc..) makes a difference from a tuners point of view. It seems the later generation ECU's are hard to "hack" but they are the ones that can usually yield the mosts gains due to the fat the the fuel and boost curves can be fine tuned to a greater degree than older generation management systems.

Boost, more boost equals more power? Not really, if you give a diesel engine more air when it's already running clean then it will make less power, fueling is far more important on a diesel than boost to create power, case in point:
Lets take Fiat's 1.9 16v Multijet engine (I believe that is has been recently replaced with a 2.0? cold someone please clearify..) In the Vauxhall astra and the Alfa 159 and various other cars it makes 150 hp and 236 lbft standard, Celtic can extract 212 hp and 327 lbft from using an extra 0.1 bar that's about 1.5 psi of extra boost! so you see, big boost isn't always required. One thing they will do is extend the boost curve so it can maintain it nearer to the redline (on most diesel 4500-5000 rpms, 5k on this engine) On most modern engines manufactures will decrease the boost and fuelling at the top end to force the motorist to change gear earlier to improve emissions and fuel economy and again so they aren't as quick as the petrol cars.
Whilest tuners will exploit the built in "slack" and make it more spritly in the topend of the revband.
Really good read cheers. I have accord 2.2 ictdi on 08. Will all this wizardry apply to me. Still looking at where to my car remapped for best results. So many out there. What sort of gains am I going to expect again so many differant story's.
 

Yugguy

Torque King
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507
Location
Rugby (expat Preston lad)
Car
Merc C220Cdi Elegan
Its a good point, my diesel remap makes the turbo come in earlier and last longer. I drove an insignia 160bhp diesel hire car the other day and I really noticed how muxh shorter the power band was.
 

davalav

Pro Tuner
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387
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Essex, England
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Mini Cooper S R56
^^
Just thinking that my self!

@ Jarrus...

if the ECU on modern diesels control boost and torque etc etc ( Like on many cars ), can you also tune them manually like our Peugeots? Like stated if the ECU controls the fuel rail to produce more power when remapped, how is that affected in older diesels that do not use an ECU to control fuelling? What I don't understand is how older diesels are controlled I guess. Say I do a stage 1 on my pug, tune the compensater, up the fuelling, as standard runs lean already, how would I keep the boost up through the Rev's say up to maximum rpms if they're is no ECU to control the fuel rail and keep it boosting.

Boggles my mind... That or I didn't understand!
 

HDi fun

TC ModFather
Points
637
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Buckinghamshire UK
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Passat 2.0 TDi
Really good read cheers. I have accord 2.2 ictdi on 08. Will all this wizardry apply to me. Still looking at where to my car remapped for best results. So many out there. What sort of gains am I going to expect again so many differant story's.

The iDTEC will go to about 220bhp with 320+ lbft.

The earlier but still excellent i-CTDi 2.2 will probably still go to 190bhp or thereabouts with around 300 lbft
 

jarrus

Pro Tuner
Points
337
Location
West Midlands, UK
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Suzuki Swift Sport
Bloody hell have we got an hour or 2? :lol:

I'll do my best...
FOr a start, no you can't tune a common rail diesel manually because there is nothing physically to change on the engine maybe you could fool the map sensor but that is would still take some kind of electrical intervention before you could turn the fuel up ,some first generation common rail engines like the Peugeot/Citoren DW10 HDI 8v used a wastegated turbo that wasn't controlled by the ECU (at least the 90 hp variant didn't but I'm not sure about the 110 hp) so you could tweak the actuator or even install a boost control of some sort, theres loads to choose from and its whole other subject to cover. Even some early VNT/VGT equipped engines could have the vane actuator altered to create boost even quicker but at the expense of making the power delievery harsher, first generation VNT's used vaccum actuators and a soleniod for boost control (ECU based) new generation ones have an electronic actuator thus removing the vaccum middle man.

Mechcanical fueling does have it's merits and draw backs but there is a bigger case for using over electronics for making power than you might think....
Davalav our cars uses what's called a rotary style injection pump,
This means it has only one plunger assembly to supply all the cylinders (unlike an inline injection pump which has one for each cylinder, I'll cover this some other time) to control fuel quantity there is a mechcanical governor which moves a collor up and down the plunger to control fuel flow (not pressure) fuel pressure is governed by a cam plate which will also control injection duration, each cam plate is cut for a specific engine and ours being an IDI engine requires relatively low injection pressure (175 bar for Bosch pump and 150 bar for Lucas pump) and long duration and the opposite for a DI engine.
Increasing the maximum fueling just adjusts the stop for the fuel collor to travel.

That was a breif description of what happens in the Bosch VE pumps
as for making power, well the Bosch VE can be modified in various ways, you can shim the governor spring which then stops the governor from pulling fuel at the top end of the rev range, you can you a larger plunger which allows you to move more fuel per stroke, larger delivery valves there are other things also like injector nozzles can easily be enlarged as cars using the VE type pump will use similar injector designs and the nozzles can be interchanged.
Also to note the Bosch VP pumps work in much the same way just with some electronic control...
This doesn't even scratch the surface on the subject really and it's very hard to explain on here,

If theres something I haven't mentioned that you wanted to know about just ask away and I'll do my best to answer
 

jarrus

Pro Tuner
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337
Location
West Midlands, UK
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Suzuki Swift Sport
Thank you for the info. Don't no why but still feel disappointed with the 190 bhp. Thought I might of got a bit more out of it. The torque looks ok though.

Believe me that's a decent hike, the limiting factor is the clutch, it just won't cope with more than 300 lbft and limiting the torque has an effect on power output...

I can tell you now that 190 hp will feel like loads...
 

davalav

Pro Tuner
Points
387
Location
Essex, England
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Mini Cooper S R56
Bloody hell have we got an hour or 2? :lol:

I'll do my best...
FOr a start, no you can't tune a common rail diesel manually because there is nothing physically to change on the engine maybe you could fool the map sensor but that is would still take some kind of electrical intervention before you could turn the fuel up ,some first generation common rail engines like the Peugeot/Citoren DW10 HDI 8v used a wastegated turbo that wasn't controlled by the ECU (at least the 90 hp variant didn't but I'm not sure about the 110 hp) so you could tweak the actuator or even install a boost control of some sort, theres loads to choose from and its whole other subject to cover. Even some early VNT/VGT equipped engines could have the vane actuator altered to create boost even quicker but at the expense of making the power delievery harsher, first generation VNT's used vaccum actuators and a soleniod for boost control (ECU based) new generation ones have an electronic actuator thus removing the vaccum middle man.

Mechcanical fueling does have it's merits and draw backs but there is a bigger case for using over electronics for making power than you might think....
Davalav our cars uses what's called a rotary style injection pump,
This means it has only one plunger assembly to supply all the cylinders (unlike an inline injection pump which has one for each cylinder, I'll cover this some other time) to control fuel quantity there is a mechcanical governor which moves a collor up and down the plunger to control fuel flow (not pressure) fuel pressure is governed by a cam plate which will also control injection duration, each cam plate is cut for a specific engine and ours being an IDI engine requires relatively low injection pressure (175 bar for Bosch pump and 150 bar for Lucas pump) and long duration and the opposite for a DI engine.
Increasing the maximum fueling just adjusts the stop for the fuel collor to travel.

That was a breif description of what happens in the Bosch VE pumps
as for making power, well the Bosch VE can be modified in various ways, you can shim the governor spring which then stops the governor from pulling fuel at the top end of the rev range, you can you a larger plunger which allows you to move more fuel per stroke, larger delivery valves there are other things also like injector nozzles can easily be enlarged as cars using the VE type pump will use similar injector designs and the nozzles can be interchanged.
Also to note the Bosch VP pumps work in much the same way just with some electronic control...
This doesn't even scratch the surface on the subject really and it's very hard to explain on here,

If theres something I haven't mentioned that you wanted to know about just ask away and I'll do my best to answer

Jesus christ! Great read and a wonderful explanation, Thank you mate. I am sure this help many people looking for same answer.
 

Toggerefc

Wrench Pro
Points
11
Location
Burnley Lancashire UK
Car
accord2.2ictdi gt
Bloody hell have we got an hour or 2? :lol:

I'll do my best...
FOr a start, no you can't tune a common rail diesel manually because there is nothing physically to change on the engine maybe you could fool the map sensor but that is would still take some kind of electrical intervention before you could turn the fuel up ,some first generation common rail engines like the Peugeot/Citoren DW10 HDI 8v used a wastegated turbo that wasn't controlled by the ECU (at least the 90 hp variant didn't but I'm not sure about the 110 hp) so you could tweak the actuator or even install a boost control of some sort, theres loads to choose from and its whole other subject to cover. Even some early VNT/VGT equipped engines could have the vane actuator altered to create boost even quicker but at the expense of making the power delievery harsher, first generation VNT's used vaccum actuators and a soleniod for boost control (ECU based) new generation ones have an electronic actuator thus removing the vaccum middle man.

Mechcanical fueling does have it's merits and draw backs but there is a bigger case for using over electronics for making power than you might think....
Davalav our cars uses what's called a rotary style injection pump,
This means it has only one plunger assembly to supply all the cylinders (unlike an inline injection pump which has one for each cylinder, I'll cover this some other time) to control fuel quantity there is a mechcanical governor which moves a collor up and down the plunger to control fuel flow (not pressure) fuel pressure is governed by a cam plate which will also control injection duration, each cam plate is cut for a specific engine and ours being an IDI engine requires relatively low injection pressure (175 bar for Bosch pump and 150 bar for Lucas pump) and long duration and the opposite for a DI engine.
Increasing the maximum fueling just adjusts the stop for the fuel collor to travel.

That was a breif description of what happens in the Bosch VE pumps
as for making power, well the Bosch VE can be modified in various ways, you can shim the governor spring which then stops the governor from pulling fuel at the top end of the rev range, you can you a larger plunger which allows you to move more fuel per stroke, larger delivery valves there are other things also like injector nozzles can easily be enlarged as cars using the VE type pump will use similar injector designs and the nozzles can be interchanged.
Also to note the Bosch VP pumps work in much the same way just with some electronic control...
This doesn't even scratch the surface on the subject really and it's very hard to explain on here,

If theres something I haven't mentioned that you wanted to know about just ask away and I'll do my best to answer
You are an absolute scholar my friend. When it comes to Diesal engines you know your stuff. There is more than enough information for me to digest. I shall go over your comments until it sinks in thank you. Toggerefc.
 
Last edited:

Charliep

Torque Junkie
Points
22
Location
Thurrock, UK
Car
Alfa GTV & 33
Bloody hell have we got an hour or 2? :lol:

I'll do my best...
FOr a start, no you can't tune a common rail diesel manually because there is nothing physically to change on the engine maybe

The air intake can be improved, which often makes a vast difference and additionally allows for a much wider mapping window before smoke becomes an issue.

The following 3 files are from Alfa Romeos with induction kits designed specifically for the the engines. The before and after runs are done within 1 hour, where the car has not being taken off the rr to make sure that all parameters possibly remain the same.

Intake revision is not the only external changes that affect the performance. Exhaust modification do too as does the removal of the DPF.

Internal changes affect performance evenly.

On the third graph the torque improved at 2000rpm by 52lb ft. The engine was an early 2.4l 5 cylinder 20v Alfa turbo Diesel. The other engines were a Fiat derived 1.9l 8v and the GM/Fiat group 16v 1.9
 

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jarrus

Pro Tuner
Points
337
Location
West Midlands, UK
Car
Suzuki Swift Sport
Looks good mate :)

Also just to clear something up, When I said there was nothing physically to change I was reffering to fuel settings liek you can on a Bosch VE or Bosch M pump, obviously on certain engines be it diesel or petrol you can make revisions to the induction system to yield useful gains.

DO you have pictures of the system before and after?
 

Toggerefc

Wrench Pro
Points
11
Location
Burnley Lancashire UK
Car
accord2.2ictdi gt
Looks good mate :)

Also just to clear something up, When I said there was nothing physically to change I was reffering to fuel settings liek you can on a Bosch VE or Bosch M pump, obviously on certain engines be it diesel or petrol you can make revisions to the induction system to yield useful gains.

DO you have pictures of the system before and after?

Does anyone know where I can get a performance panel filter for my accord 2.2 Ictdi. Tried K&n pipercross green. Apparently they don't make one for my car. Getting remapped in next few weeks. Been told to avoid the likes of the typhoon air filter set up from k&n because of the effect it has on sensors and the effect it also has on torque at the bottom end.
 

Toggerefc

Wrench Pro
Points
11
Location
Burnley Lancashire UK
Car
accord2.2ictdi gt
Try searching for other honda 2.2 ictdi,like the civic. Chances are the airbox might be the same.

Yugguy thanks for reply. But surely if the air box is the same my friend. Then the filter is the same. So why do not say you can have one for the civic it's exactly the same. Or better still just say it's for the accord civic bla bla bla. Manufacturers don't make it easy. I can see already what this journey is going to be like. But hopefully it will be worth it. Got about a grand to spend on my accord. Not an enormous amount I know but a remap filter and service should come to about £ 500 quid. With the rest thinking about new set of 18" wheels and tyres to replace my original 16" ers. That should cover it for now.
 

Charliep

Torque Junkie
Points
22
Location
Thurrock, UK
Car
Alfa GTV & 33
Looks good mate :)

Also just to clear something up, When I said there was nothing physically to change I was reffering to fuel settings liek you can on a Bosch VE or Bosch M pump, obviously on certain engines be it diesel or petrol you can make revisions to the induction system to yield useful gains.

DO you have pictures of the system before and after?

Thanks for clearing this.

I have pictures installed.

Does anyone know where I can get a performance panel filter for my accord 2.2 Ictdi. Tried K&n pipercross green. Apparently they don't make one for my car. Getting remapped in next few weeks. Been told to avoid the likes of the typhoon air filter set up from k&n because of the effect it has on sensors and the effect it also has on torque at the bottom end.

Although I am not a fan of K&N as well as the fact that the typhoons were developed in response to our air intake systems I have to be truthful.

The people who have told you that the typhoons affect sensors as well as losing bottom end torque have no clue what they are talking about. The typhoons are some of the better intakes (at least most of them) although they are not the best you can get for reasonable money.
 

jarrus

Pro Tuner
Points
337
Location
West Midlands, UK
Car
Suzuki Swift Sport
Panel filter are really not worth your money they offer absolutely no gains whats so ever, the filter itself is the least restrictive part of the system,

Autospeed did a nice article on the subject which many of you will be familier with which back up my claims, ill post it up when i find and finished working on the motor.
 

Toggerefc

Wrench Pro
Points
11
Location
Burnley Lancashire UK
Car
accord2.2ictdi gt
Panel filter are really not worth your money they offer absolutely no gains whats so ever, the filter itself is the least restrictive part of the system,

Autospeed did a nice article on the subject which many of you will be familier with which back up my claims, ill post it up when i find and finished working on the motor.
Nice one for the advice. What would you recommend got about £200 quid to spend on that part of the car if need be. Just don't know what to get for the best. Here so many differant story's out there.
 

Jakeymd

The Torque Meister
Points
102
Location
Ashbourne
Car
Ford Focus 2.0 TDCi
get the dpf removed if it has one. That'll free up some ponies. I blocked up my egr today and the results were astounding If your want to do these you might have to get software removed from the ecu. Best time to do this is during the remap. Have you heard of the torquecars dyno day on the 17thmarch?
 

pgarner

TC ModFather
Points
417
Location
Lockerbie, SW Scotland
Car
Octy smoke machine
mmm DPF removal is alot harder now, well its more like cat removal in petrols. alot harder to pass the smoke test as limits have been tightened up.
and unlike the cat its not just a case of refittting it for the MOT as it needs to be programmed in and out of the ECU
 

Toggerefc

Wrench Pro
Points
11
Location
Burnley Lancashire UK
Car
accord2.2ictdi gt
get the dpf removed if it has one. That'll free up some ponies. I blocked up my egr today and the results were astounding If your want to do these you might have to get software removed from the ecu. Best time to do this is during the remap. Have you heard of the torquecars dyno day on the ?
Torque Dyno day sounds mint. Where will this event take place. I want to go. Have you any more info.
 

Harvey

Tuner
Points
157
Location
Darlington
Car
Vectra CDTi 280/437
What exactly are the parameters for a Diesel engine remap?

There is presumably no timing/spark to advance so I'm guessing it is mainly fuel quantity and boost duration/amount.

The requirements for mapping a diesel will vary from say a VAG diesel unit to a common rail unit such as the 1.9 Fiat CDTi as used on SAAB, Vauxhall, GM/Opel, Fiat and Alpha Romeo.

On the common rail engine the following perameters can be adjusted for best power and earliest spool but with the objective of avoiding the onset of black smoke.
Fuel rail pressure can be lifted.
Injector timing can be advanced or retarded.
Injector pulse width can be adjusted.
Boost targets can be altered.
The objective is maximum power with minimum smoke with torque as early in the rev range as possible.
A modern ECUs with a VNT turbo is very complex and there will be numerous torque limits that need to be raised and chances are that there will also be speed limits that can come into play in 5th and sixth gear so best get rid of these.

With any diesel the objective is to get better breathing ie more air into the engine. This is not restricted to the inlet side as the exhaust side can also hold back the through flow of air but until you add more fuel you will not get the benefit of the improvements you have made.
 

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