25/04/2026
๐ง๐ต๐ฒ ๐ฟ๐ฒ๐ฎ๐๐ผ๐ป ๐๐ผ๐บ๐ฒ ๐ฝ๐ฒ๐ผ๐ฝ๐น๐ฒ ๐ฎ๐ฐ๐ฐ๐ฒ๐ฝ๐ ๐ฏ๐น๐ฎ๐ฐ๐ธ ๐๐บ๐ผ๐ธ๐ฒ ๐ถ๐ ๐๐ถ๐บ๐ฝ๐น๐ฒ.
It is cheaper.
To burn more fuel cleanly, a diesel needs enough air to go with it. Once the turbo, intercooler, injectors, exhaust, or general hardware setup has reached its useful limit, you cannot just keep adding fuel and expect a clean result. The proper answer is often more air, which usually means a better turbo setup, supporting hardware, and proper calibration to match it.
That costs considerably more than a cheap map, so some people choose to accept smoke as the compromise. That is their choice, and this is not about saying the customer is wrong if they understand the compromise and choose to run the car that way.
The problem is pretending there is no compromise or as is with some "tuners" being in denial about there even being a compromise or risk at all!
Black smoke is not magic power, and it is not โjust what diesels doโ. In tuning terms, it is usually soot from fuel that has only partially combusted, because the engine has been given more fuel than the available air can burn cleanly. That can come from too much fuel, poor control of when that fuel is delivered, or simply pushing the setup beyond the airflow it has available.
There is also a big difference between a little smoke and clouds of smoke. A light haze you might accept and say is normal, especially during spool or a quick transient moment, may be something some people choose to accept. But when it is throwing out thick clouds of black smoke, as is often seen with aggressive PD tuning, that is a much bigger compromise.
At that point, it is impossible to pretend there is no extra heat, no extra stress, and no damage being done over time.
Yes, the car might feel strong. Yes, it might make power. Yes, it might run like that for a while. But โit has not broken yetโ is not the same as โit is safeโ.
Excessive black smoke often means higher combustion temperatures and higher exhaust gas temperatures. That is the sort of thing you pick up properly with an EGT sensor, not by guessing from the smoke level alone.
High EGT does not always kill an engine instantly. Heat damage can be gradual, with repeated heat cycles and sustained high temperatures taking their toll long before the engine finally shows an obvious fault.
Excessive EGT can crack exhaust manifolds and cylinder heads. Exhaust valves can suffer from the heat and eventually fail. Aluminium parts are often among the first to be affected because aluminium softens and melts at a lower temperature than steel or cast iron.
Pistons, cylinder head areas, valves, turbochargers, manifolds and gaskets can all suffer when heat is pushed too far.
The turbocharger is also under extra stress. More fuel often means more heat and more exhaust energy, which can push the turbo outside its safe working range. That can mean overspeed, bearing wear, cracked housings, sticking VNT mechanisms, boost control issues, or eventual turbo failure.
The exhaust system suffers too. Manifolds, turbine housings, downpipes, flexis, catalytic converters and DPFs, where fitted, are all exposed to more soot and heat. A DPF especially does not enjoy excessive soot loading, and repeated high-temperature events can shorten its life dramatically.
Then there is the oil. Excess soot and heat can contaminate the oil faster, increase wear, and make servicing even more important. On engines already getting older, that extra stress can be the difference between something lasting and something letting go.
This is why copying what someone else has done is not the same as understanding the risk. Just because another car made a certain power figure and survived for a period of time does not mean the same approach is safe, or that no damage is happening in the background.
Every engine has limits. Airflow limits. Turbo limits. Fuel system limits. Cooling limits. Exhaust temperature limits. Once you push beyond those limits, something has to take the punishment.
Accepting black smoke as a compromise is one thing. Pretending black smoke is harmless is another.
If the hardware cannot supply enough air, the clean answer is more air, not just more fuel. If someone chooses the cheaper route and accepts the smoke, that is their decision.
But nobody should be pretending excessive black smoke is fine, harmless, or normal.
This is not just our opinion either. Banks Power has covered this for years: black diesel smoke is soot from fuel that has not fully combusted, adding fuel without enough air raises EGT, and hotter EGTs can damage the engine. In simple terms, more smoke is not free power, it is wasted fuel, heat, soot and risk.
If you want to see the opinion of Gail Banks on the issues, there are are easy to digest links worth reading:-
Banks Power - Turbo-Diesel Fact & Fiction
https://official.bankspower.com/tech_article/turbo-diesel-fact-fiction/
Banks Power - Hopping Up the Turbodiesel
https://official.bankspower.com/magazine/hopping-up-the-turbodiesel/
Banks Power - Why Big Air Density Makes a Big Difference
https://official.bankspower.com/tech_article/why-big-air-density-makes-a-big-difference/
Banks Power - Why EGT is Important
https://official.bankspower.com/tech_article/why-egt-is-important/
Banks Power - Ford 7.3L Power Strokes Need This
https://official.bankspower.com/insider_news/ford-7-3l-power-strokes-need-this/
๐ ๐๐ป๐ฑ๐ฒ๐ฟ๐๐๐ฎ๐ป๐ฑ ๐๐ต๐ฒ๐ฟ๐ฒ ๐ฎ๐ฟ๐ฒ ๐ฎ ๐ป๐๐บ๐ฏ๐ฒ๐ฟ ๐ผ๐ณ โ๐๐๐ป๐ฒ๐ฟ๐โ ๐๐ต๐ผ ๐๐ต๐ถ๐ป๐ธ ๐๐ต๐ฎ๐ ๐๐ข๐๐-๐น๐ฒ๐๐ฒ๐น ๐๐บ๐ผ๐ธ๐ฒ ๐ถ๐ ๐ต๐ผ๐ ๐ถ๐โ๐ ๐ฑ๐ผ๐ป๐ฒ. ๐๐ฒ๐โ๐ ๐๐ฒ๐ฒ ๐๐ต๐ฒ ๐๐๐ง ๐น๐ผ๐ด๐ ๐๐ผ ๐ฏ๐ฎ๐ฐ๐ธ ๐๐ฝ ๐๐ผ๐๐ฟ ๐ฐ๐น๐ฎ๐ถ๐บ๐. ๐ ๐ฎ๐๐๐๐บ๐ฒ ๐๐ต๐ฒ๐ป ๐๐ผ๐ ๐ฑ๐ผ ๐๐ต๐ฒ๐๐ฒ ๐ฃ๐๐ญ๐ฏ๐ฌ๐ ๐๐ผ๐ ๐ต๐ฎ๐๐ฒ ๐๐ผ๐บ๐ฒ ๐๐ฎ๐ ๐๐ผ ๐ฑ๐ฒ๐๐ฒ๐ฟ๐บ๐ถ๐ป๐ฒ ๐๐๐ง ๐๐ฒ๐บ๐ฝ๐, ๐ผ๐ฟ ๐ฎ๐ฟ๐ฒ ๐๐ผ๐ ๐ท๐๐๐ ๐๐ถ๐ป๐ด๐ถ๐ป๐ด ๐ถ๐?
Show us some pics of how you measure the EGT whilst you're at it!
PS I did ask ChatGPT to generate the image, seems to have nit a raw nerve with some, maybe a little too close to the truth lol.
If you want a smoke map, we will do it, just ask for it by the correct name. The death map!
