View Single Post
Old 12-09-2019, 02:19 AM   #4 (permalink)
mpg_numbers_guy
Master EcoModder
 
mpg_numbers_guy's Avatar
 
Join Date: Feb 2018
Location: VA
Posts: 1,363

Toby - '13 Toyota Prius C
90 day: 64.01 mpg (US)

Daz - '15 Mazda 3 iTouring w/ Tech Package
90 day: 38.2 mpg (US)
Thanks: 321
Thanked 480 Times in 365 Posts
Quote:
Originally Posted by TaylorL View Post
Thanks for the welcome! I've been looking at the torque app as a cheaper alternative to a scangauge for testing and monitoring purposes. Do you have any input on that? I do a lot of engine off coasting, one of my concerns is that the app may disconnect briefly when the engine is killed? I'm also curious if the torque app has a way of manually adjusting the MPG readout for accuracy?
Not really. Torque is good mostly only for instantaneous fuel economy - which isn't even accurate. All it's good for is seeing higher numbers is better and lower numbers is worse. Accuracy is garbage.

EDIT: One of the required settings for FE instrumentation with Torque is to input your car's engine size. Not sure what effect that has on changing the FE value; I never messed with it when I was using Torque.

For example, if your MPG is > 99.9, it will display up to 256 MPG, but it won't count any time above 99.9 MPG as part of your fuel economy trip log. Therefore any downhill driving on the highway wasn't always counted, hence why the highway FE was grossly understimated.

Torque also seems to underestimate how much fuel is used to accelerate. I could get the reading above 65 MPG by doing Pulse-&-Glide (which turned out to be 50-55 mpg max). The readings were artificially high because it didn't seem to account for how much gas was being used.

Maybe they've updated it since, but the only times I was able to get an accurate reading was when my split of highway/city driving was even enough where the +20% error and -20% error mostly canceled out. Or if when I drove on the highway I kept on the gas even on the downhill to keep the MPG just below that 99 mpg threshold, but that just resulted in a little lower MPG overall.

A Scangauge works best because you can calibrate it over a full tank. Is Torque better than nothing? Sure, any slightly accurate fuel ecnonomy instrumentation better than no instrumentation, but if you're looking for accuracy, don't look for a bluetooth dongle + smartphone app.

Quote:
Originally Posted by TaylorL View Post
I'm currently running 53 PSI, they were around 47 when i did that 47.5 MPG tank. I read a write up MetroMPG did about rolling resistance with higher tire pressures. I haven't yet done any testing of my own but it seemed like pressures beyond the max sidewall of 44 offered very minimal returns. As of right now I likely wont exceed 53, I feel that's a good safe number with reduced rolling resistance.
Yes, beyond 44 PSI and the gains are smaller; beyond 60 PSI and the gains are smaller yet. They're still there, but they're a lot harder to measured.
__________________
2013 Toyota Prius C 2 (my car)


2015 Mazda 3 iTouring Hatchback w/ Tech Package (wife's car)

Last edited by mpg_numbers_guy; 12-09-2019 at 02:26 AM..
  Reply With Quote
The Following 2 Users Say Thank You to mpg_numbers_guy For This Useful Post:
MetroMPG (12-12-2019), Xist (12-10-2019)