Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - 1.9 TDI 105cv from 44.7 mpg to 53 mpg higway

ausias · 08-20-2013, 08:22 AM

with torsion value you are advanding or retarding the injection in degrees of crank rotation so the injection timing in seconds (or miliseconds) changes depending on what speed (and angular acceleration, boost, temps, and dozens of other values).
Advancing 3º it is not a small adavance, because it means that injectioion pump being pushed to start 6º before and it will represent a large time of advance when low rpms and no noticeable (or worst) changes in performance (in terms of power and/or effiicinecy).
Euro 4 engines and higher have in some regions of the map thing retarded 2º so you only need to fine FINE tune your engine in a range of 1º of crank to compensate, but you are fooling the maths a little on high loads and ranges. IN terms of efficiency sometimes the injection is retarded but the engine has more pressure in the cilinder because of gas recirculation EGR so efficiency is almost the same but with less pollutants being generated.
So big differences in real performance and efficeincy (there are not the same) are between the crank angle too retarded or advanced. And lot of explanation is needed.
To sum up, engine will run and start with Torsion in the range 3º advanced and out of range retarded (I gess a bit higher than 6º retarded).
Volkswagen wants tdi to be between +3 and -3, and some cars have the sensor in the range of -6 to +6. But if you want your injection pump or pump injectors being synchronized with the ECU values and getting all the fuel efficiency and max power you will need to fine tune to +-1º. (For me prefered 0 to 1º adavanced in the 2006 1.9 TDI PD BXE i had)
Elasticity is the way to go because it means that the ECU get from sensors the correct values in all the range so it injects the specified amount of fuel according to air. REmember that your injection is controlled with several limitats and power-torque curves by the ECU. so you are feeling the power that should your engine have. But it was lost because of not fine tuned.

If you want to go further you need to do a custom ECU with pressure sensors, back pressures, etc. maybe Vekke should answer more accurately. http://ecomodder.com/forum/showthrea...-2l-18235.html

08-20-2013, 08:22 AM	#10 (permalink)
ausias Burning oil to move air. Join Date: Aug 2011 Location: Valencia (Europe) Posts: 126 ausiasmobil - '06 Seat Leon 1.9 TDI Reference 90 day: 40.22 mpg (US) EcoTxec - '99 Skoda Octavia 1.9 TDI 110 cv Laurin & Klement 90 day: 52.85 mpg (US) Thanks: 92 Thanked 37 Times in 25 Posts	with torsion value you are advanding or retarding the injection in degrees of crank rotation so the injection timing in seconds (or miliseconds) changes depending on what speed (and angular acceleration, boost, temps, and dozens of other values). Advancing 3º it is not a small adavance, because it means that injectioion pump being pushed to start 6º before and it will represent a large time of advance when low rpms and no noticeable (or worst) changes in performance (in terms of power and/or effiicinecy). Euro 4 engines and higher have in some regions of the map thing retarded 2º so you only need to fine FINE tune your engine in a range of 1º of crank to compensate, but you are fooling the maths a little on high loads and ranges. IN terms of efficiency sometimes the injection is retarded but the engine has more pressure in the cilinder because of gas recirculation EGR so efficiency is almost the same but with less pollutants being generated. So big differences in real performance and efficeincy (there are not the same) are between the crank angle too retarded or advanced. And lot of explanation is needed. To sum up, engine will run and start with Torsion in the range 3º advanced and out of range retarded (I gess a bit higher than 6º retarded). Volkswagen wants tdi to be between +3 and -3, and some cars have the sensor in the range of -6 to +6. But if you want your injection pump or pump injectors being synchronized with the ECU values and getting all the fuel efficiency and max power you will need to fine tune to +-1º. (For me prefered 0 to 1º adavanced in the 2006 1.9 TDI PD BXE i had) Elasticity is the way to go because it means that the ECU get from sensors the correct values in all the range so it injects the specified amount of fuel according to air. REmember that your injection is controlled with several limitats and power-torque curves by the ECU. so you are feeling the power that should your engine have. But it was lost because of not fine tuned. If you want to go further you need to do a custom ECU with pressure sensors, back pressures, etc. maybe Vekke should answer more accurately. http://ecomodder.com/forum/showthrea...-2l-18235.html __________________ Sold: