54 minutes ago, lichfielddriver said:

dirty air cant make clean air by burning............its impossible

Nothing to do with it being dirty.

 

Basically, the recirculated gas from the exhaust has much less oxygen in it, so it increases the portion of the gas in the cylinder that is inert (i.e. won't support combustion). But it's still gas that will expand once combustion occurs to provide power. Less oxygen in the cylinder means less fuel is injected and combusted resulting in lower cylinder temperatures and less NOx.

 

 

18 hours ago, chimaera said:

Nothing to do with it being dirty.

 

Basically, the recirculated gas from the exhaust has much less oxygen in it, so it increases the portion of the gas in the cylinder that is inert (i.e. won't support combustion). But it's still gas that will expand once combustion occurs to provide power. Less oxygen in the cylinder means less fuel is injected and combusted resulting in lower cylinder temperatures and less NOx.

 

If this is right why do EGR and DPF units fail?... over to you

 

I didnt know soot was a fuel

 

Edited 19 April, 20179 yr by lichfielddriver

https://www.facebook.com/photo.php?fbid=1506360906043485&set=a.196527730360149.54473.100000087708319&type=3

Edited 19 April, 20179 yr by lichfielddriver

basically............choke the engine then....

 

so all the free flow, big valves, open chambers and old school tuning was wrong?

4 minutes ago, lichfielddriver said:

If this is right why do EGR and DPF units fail?... over to you

 

There are many reasons for components to fail... Not sure how that's related to the post from @chimaera.

 

8 minutes ago, lichfielddriver said:

 

The link between NOx/PM and combustion conditions are well understood and documented science. It might help this thread progress help if you took some time to understand it.

 

Just now, lichfielddriver said:

basically............choke the engine then....

 

so all the free flow, big valves, open chambers and old school tuning was wrong?

Emissions control systems can reduce the power/efficiency of the engine in an effort to keep emissions within the limits.

 

As with all modern engine design it's a compromise between reliably, power, efficiency and emissions. Surely this isn't news to you?

Emissions control systems can reduce the power/efficiency of the engine in an effort to keep emissions within the limits.

 

 

VAG tried that...........and have 8000 EGR valves on back order tp prove it

BTW............ its deleting not delating.......nor dilating

Reckon the Audi Le Mans diesels have EGR and DPF fitted?

 

18 minutes ago, lichfielddriver said:

Reckon the Audi Le Mans diesels have EGR and DPF fitted?

 

Do they need to meet any emissions requirements?

 

Rather than adding multiple seemingly random posts, please can you clearly and concisely state the point you are actually trying to make?

Deleting the EGR, DPF, cat and just about any anti emission equipment will make the engine more efficient performance wise at the cost of emissions. My 1.9 Octavia was a much more "diesel like" car for driving, it would happily chug along at 30 mph in top gear and always returned good economy. It would be interesting to know how much NOX these older engines produced, it could certainly produce a lot of smoke when accelerated hard but that seems typical of all older diesels but big lumps are less harmful than the smaller ones aren't they? Attempting to make diesel engines drive more like petrol ones with equivalent power has possibly made the NOX problem worse, higher turbo boost pressures means higher combustion chamber temperatures so chuck some inert gas in there to dial it back, increase the turbo boost to regain the lost power and we are on a vicious circle. Of course you could always lie about it!

If deleting the EGR/DPF is so bad is not having the VAG "cheat fix" making me arrestable too?

9 minutes ago, lichfielddriver said:

If deleting the EGR/DPF is so bad is not having the VAG "cheat fix" making me arrestable too?

 

EGR/DPF removal will increase emissions, it's that simple. It may be better for engine performance or fuel economy it done properly.

 

The emissions fix is completely optional in the UK and I haven't seen any posts suggesting that you or anyone else will or should be arrested for refusing it.

Oh yeah then diesel gate happened and all the emission promises became bull****...