Tweet
Okay, some more diesel tuning theory and experience here:
As Lee pointed out, a tuned diesel engine will smoke like mad because there's no more air to burn the fuel. Diesel has to be burnt in lean mixtures and the air in the combustion plays 2 roles: lower smoke and keep combustion temps down.
Thus, proper diesel tuning involves raising the injected quantity, increasing boost about proportionally AND also increasing injection advance in order to make sure the end of the injection cycle won't happen on top of a piston at Top Dead Center, which might ruin your engine in the long term.
This is why Powerboxes, tuningboxes and other bull****e gimmicks will never be a proper way of increasing an engine's output. All they can affect is the injected quantity, and they do it well, but as they don't touch boost and injection advance, the engine smokes a lot more, produces more power as well (from the heat generated by the diesel burnt in a rich mixture condition) and will eventually burn holes in the pistons in case the settings go a bit too far.
The problem is that even a remap can produce the same results, some companies such as Dooperchips and powerproms (I've changed the names on purpose) only do the same thing as a tuning box in their mapping, because increasing boost means hours of disassembling data in order to find one single value that limits boost, and because they don't have the time nor the knowledge to do so. Plus, what does it matter? When one increases boost, power goes down a bit, so it's better to have more power than anyone else (this is how some people claim 150 "safe and reliable" HP out of a 1.9 TDI 110 BHP engine), even if it smokes more and the engine will last less.
So beware who you buy your TDI chip from, I used to think some generalist companies used to know at least TDIs if not S2s, but the fact is that they don't know **** and they do produce dangerous products.
Hmmm, Doug, BTW, could you notice any excessive smoke from my remaps on either the Polo or the A4? I can't remember....
Cheers,
Mihnea, ranting at bad tuners
As Lee pointed out, a tuned diesel engine will smoke like mad because there's no more air to burn the fuel. Diesel has to be burnt in lean mixtures and the air in the combustion plays 2 roles: lower smoke and keep combustion temps down.
Thus, proper diesel tuning involves raising the injected quantity, increasing boost about proportionally AND also increasing injection advance in order to make sure the end of the injection cycle won't happen on top of a piston at Top Dead Center, which might ruin your engine in the long term.
This is why Powerboxes, tuningboxes and other bull****e gimmicks will never be a proper way of increasing an engine's output. All they can affect is the injected quantity, and they do it well, but as they don't touch boost and injection advance, the engine smokes a lot more, produces more power as well (from the heat generated by the diesel burnt in a rich mixture condition) and will eventually burn holes in the pistons in case the settings go a bit too far.
The problem is that even a remap can produce the same results, some companies such as Dooperchips and powerproms (I've changed the names on purpose) only do the same thing as a tuning box in their mapping, because increasing boost means hours of disassembling data in order to find one single value that limits boost, and because they don't have the time nor the knowledge to do so. Plus, what does it matter? When one increases boost, power goes down a bit, so it's better to have more power than anyone else (this is how some people claim 150 "safe and reliable" HP out of a 1.9 TDI 110 BHP engine), even if it smokes more and the engine will last less.
So beware who you buy your TDI chip from, I used to think some generalist companies used to know at least TDIs if not S2s, but the fact is that they don't know **** and they do produce dangerous products.
Hmmm, Doug, BTW, could you notice any excessive smoke from my remaps on either the Polo or the A4? I can't remember....
Cheers,
Mihnea, ranting at bad tuners
not sure how comfortable it would be driving in that futuristic leather bondage gear though. 
He doesn't like the idea though, apparently it's my own fault for driving a thirsty car 
Comment