Quote:
Originally Posted by ausias
I closed again my upper grill wich added to my actual fine tuning in the camshaft timing now I got this really amazing figures in L/100km@km/h:
3.80@82
4.02@94
5.50@122
Time to write a Success Story! +15 to +21 % us mpg, and -13 to -18% on fuel consumption in L/100km, Congratulations to me. 
http://ecomodder.com/forum/showthrea...3-a-19233.html |
Maybe It's time to Myth Busted Camshaf timing feuel saving.
The real thing is throttle response changed a lot if cam timing is advanced retarded or out of range but in a starting engine region (go out of range and soon car will not start and will get cold start problems). Top Speed changes are very noticiable between -5% to +3% from my standar timing. The best result of +3% was obtained when my Torsion or CAm Timing is set to 0.0 and my aero addons included low spoiler, fixed wheel spoilers (I had broke right one) and 90% upper grill block with cold air intake and top of radiators(a/c condenser, intercooler and coolant radiator) wind exposed. REaltive measured fuel consumption is about -6%, if efficiency supposed constant drag Force will be -6% and -8% drag coefficient could be responsible of that change (drag is a parabollic function of speed, at large speed and with rolling ressitance negligible aproximations could be done: 2 times the speed need 4 times de force needed, or 103% speed means 106.09% force, or 96% force means sqrt(1/0.96)=102% speed). Because at Top Speed I measured -4% L/100km but max power torque curve being limited by ECU it seems and less throtle means less Load and lower efficiency (in a non linear maner
Brake Specific Fuel Consumption (BSFC) Maps - EcoModder) like my cd go down again and is near 0.3. If my own car height, width, 3d fronal shape is equal to Seat Leon Ecomotive (almost equal front original grill not fitting in 2005-2008 versions, and only in restilyng) if I add central lower spoiler and did my own block grill, I think my expected cd of what VW says is coherent result of my numerical model curve-fitting.
I lost in my own explanation
I think I overanswered your questions.
I'm sure my aerodynamical improvements are working, but I suspect BOSCH EDC16 ECU is missing some high precision sensors. Maybe when ECU says 7.0 L/100km at 122 (+2.9 cam) it's not 107% fuel consumption but 93%. I will test with full tanks or large trips of hundred of kms.
I think 10% improvement in specific fuel consumption its the limit, becuase better of 190g/Kwh BSFC I think is difficult of an engine expected to do 200 or 210 g/KWh as best.
I know the same engine with ECU maps could range from 190 to 260 g/Kwh, 166 bhp to 230 bhp versions, best of 200 but 250/260 at full power 4000rpm etc. I'm motivated to learn how to obtain DIY ECU optimization on fuel economy if I can without spending a lot of money (300 to 400€) on a chiptunner. I would need first doing a backup of my ECU, after chip tuning other backup and comparing two binaries (Is there any software to do this? ). These firsts attempts challenged me.
It will be helpful if any of you could do the same tunning of the camshaft and test on full tank average L/100km or mpg mileages, and share our data. Or if you try some data logging OBDII.