As it gets hot a humid here, I'm very sure I'm seeing worse mpg when the temp is 95F PM ride from when it's 80F AM SG data

Anyone else see that?

Do we know what the best ambient temp is for Eco?

 

i would say 25F-32F and dry using non-winterized gas.

 

I am with you Paul, it was 92 here in the dirty south. A/C is a must unless you want to ride in the fat farm death trap. Hell, I might be able to loose weight and save on gas at the same time if I don't use the A/C!

 

My guesses
Not good for mpg:
Hot weather
High Altitude
High Humidity

Since running the AC might be harder on fuel use- testing with lower temperature like 40 degrees means no AC- this is good.

Note that low temps are not good for battery driven hybrids since power is lower with low temps.

see
The Center for Auto Safety

 

Intake air temps of 75-90 with low humidity seem to give good results. Cold air (<50°F) is no good because it requires more fuel to be dumped to keep the correct air/fuel mix, and the engine takes longer to heat up.
Some hypermilers build hot-air intakes which pull hot air off of the catalytic converter to maintain warmer intake air temps, as well as engine grille blocks so less fuel is burned to keep the engine at operating temp.

 

My SG intake temp in the afternoon is 100 to 110F