best throttle setting for fuel economy
best throttle setting for fuel economy
(OP)
I have the option to alter my throttle setting on my Subaru. there are 3 different settings:
- economy
- sport
- SportSharp
I personally do not see any difference between economy and sport...i think in eco it just keeps the torque converter locked longer before unlocking but i'm not sure. otherwise the throttle maps are both 'numb' meaning the first 5-10% of pedal depression does very little but then it suddenly ramps up to 100% with just 1/3 accelerator pedal depression. For sportsharp, which is my favourite, the throttle is very responsive. The first ~15% pedal input opens the throttle generously. In sportsharp it's very difficult to keep vacuum high and my MPG readout never really goes below 8L/100km during steady throttle functions. But this setting forces me to do mini pulse and glides resulting in high MAP or TPS to keep a steady speed. Shift points are the same if I keep the tranny in D or Drive... it shifts at 2000-2800 RPM based on how fast I roll on the thorttle in normal driving. The SportSharp setting, unlike eco/sport, keeps throttle linear after the first ~15% 'surge' all the way to ~2/3 accelerator input ( So SportSharp is sensitive first ~15% but it starts to tame after,,, good for the track?).
so the question is assuming all other parameters such as shift points, timing and fuel ratio stay the same, which type of throttle setting is best for fuel economy with mix of city and highway?
- economy
- sport
- SportSharp
I personally do not see any difference between economy and sport...i think in eco it just keeps the torque converter locked longer before unlocking but i'm not sure. otherwise the throttle maps are both 'numb' meaning the first 5-10% of pedal depression does very little but then it suddenly ramps up to 100% with just 1/3 accelerator pedal depression. For sportsharp, which is my favourite, the throttle is very responsive. The first ~15% pedal input opens the throttle generously. In sportsharp it's very difficult to keep vacuum high and my MPG readout never really goes below 8L/100km during steady throttle functions. But this setting forces me to do mini pulse and glides resulting in high MAP or TPS to keep a steady speed. Shift points are the same if I keep the tranny in D or Drive... it shifts at 2000-2800 RPM based on how fast I roll on the thorttle in normal driving. The SportSharp setting, unlike eco/sport, keeps throttle linear after the first ~15% 'surge' all the way to ~2/3 accelerator input ( So SportSharp is sensitive first ~15% but it starts to tame after,,, good for the track?).
so the question is assuming all other parameters such as shift points, timing and fuel ratio stay the same, which type of throttle setting is best for fuel economy with mix of city and highway?





RE: best throttle setting for fuel economy
Anything that causes the transmission to stay in a lower gear (higher revs) than absolutely necessary (e.g. your "sport-sharp" mode) is not going to help economy.
If "eco" actually does keep the torque converter locked more, it should help a little.
These gizmos cannot actually do anything that really improves the efficiency (no "lean cruise", no playing with ignition timing, etc) because they still have to comply with emission standards.
RE: best throttle setting for fuel economy
RE: best throttle setting for fuel economy
It's physically impossible for a push button on the dashboard to change the mechanical gear ratios in the transmission.
Running at anything other than stoichiometric air/fuel is verboten for 3-way-catalyst emission reasons during light-load cruise and gentle driving that predominates normal driving behaviour.
They CAN change transmission calibration (for automatics) but usually only for the worse ("sport" mode) or only for very slim gains at the expense of driveability (by locking up the torque converter and shifting early on the verge of bogging the engine or getting rough shifts in some conditions). Stock, default programming is usually already pretty close to the best that the calibration folks can come up with.
They can and do change the calibration of the accelerator pedal, which is always drive-by-wire nowadays, and by making the driver have to do more in order to "floor it" or get close to full engine load, it encourages more economical driving. But the driver could do exactly the same in the absence of that "eco" button simply by driving more gently.
RE: best throttle setting for fuel economy
with all you monitoring capabilities I'd think you could tell "us" the answer.
One unmeasureable part might be what feels acceptable to you.
IE, if the data says "short shift" at 2300 rpm and open the throttle 37%, and the average speed and trip ET will be the same as brisk conventional driving, but that feels doggy to you, would you drive that way, or even accept the data as real?
RE: best throttle setting for fuel economy
je suis charlie
RE: best throttle setting for fuel economy
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Of course I can. I can do anything. I can do absolutely anything. I'm an expert!
RE: best throttle setting for fuel economy
RE: best throttle setting for fuel economy
http://ecomodder.com/wiki/index.php/Torque_Convert...
Some groups note "simply" adding a lock up transmission from a later model is worth a couple of MPG on a 25 mpg Volvo in general mixed driving.
Did you get your fuel and ignition maps to you liking?
RE: best throttle setting for fuel economy
40mphor higher speeds. The only time I get a downshift is on highway merging. Otherwise pulse and glides are mostly in locked TC mode in overdrive since I don't need any more torque. My mileage for cruising on highway is horrible at the moment with cold temperatures (-4*f). I barely score 26mpg highway @ speed limit. Summer time I get a much healthier ~33mpg.RE: best throttle setting for fuel economy
RE: best throttle setting for fuel economy
"Schiefgehen will, was schiefgehen kann" - das Murphygesetz
RE: best throttle setting for fuel economy
Once the engine has warmed up there should be no difference in economy.
je suis charlie
RE: best throttle setting for fuel economy
RE: best throttle setting for fuel economy
RE: best throttle setting for fuel economy
Regardless there is no way the highway economy should be 27% worse. The fuel mapping is incorrect.
je suis charlie
RE: best throttle setting for fuel economy