Thanks Stevejust.
WOW what a long post this turned out to be! Sorry about that.
4 Minutes I would guess about 2 miles.
I think you are doing pretty good for 45MPG over that distance, given many stop lights along the way. If you are not doing this already try to time the lights if possible so you don't have to stop: if you have to stop on a decline leave a space or two in front of you and begin rolling before the car in front does, accelerate gradually etc.
My drive to work:
Leave house at 4:20PM
Over all trip is 50 hilly Miles from rural N. Georgia into Atlanta.
22 miles on country highway 45-55MPH limit, first 11 miles several Kfeet incline, the rest of the way is a gradual decline. At 22 miles I jump onto a moderately busy I85 freeway into Atlanta. All the way is some larger hills with a few "monster" hills.
2 miles from work I exit onto one of the worst traffic intersections of the city at 5:15PM. 5 stoplights (On somesevere inclines) usually drop my average MPG by 1 or 1.5.
Arrival MPG is typically 59-61 working the A/C load
if I must going downhill only.
MPG is typically 60-62 without the A/C.
Highway speeds are typically 38-55MPH and freeway is 52-65MPH.
Today was running very late and had to take freeway all the way.
Working the A/C load only occasionaly and always downhill got me 56.3MPG.
This is driving 60-72MPH all the way.
Trip home:
Leave work at 2:00AM and jump right onto an almost deserted freeway.
First 30 miles to the exit is a gradual incline of several thousand feet. A real MPG battle.
I typically exit the freeway and have around 55MPG onto generally flat 12 miles broken up with constant hills. (Does that make any sense?)
Only here I get a chance to get some lean burn. My last 11 miles are pretty much constantly gradual decline and keep it in high leanburn (+100MPG or more) most of the way home. 3 miles from home begins a mile long valley which begins 4 MONSTER hills...these things likely total 1 to 1.5Kfeet over 2 miles. They usually lower by 1MPG.
Since by this time it is 3:05AM the roads are abandoned. I pass the only stop light in town, gradually make my speed to the limit (35MPH), turn my engine off, reboot the car and roll 1.5 miles right up into my subdivision. After a BRIEF restart for a very short burst of power I roll up the road, through the gate and down the hill right into the parking cover.
Typically get 60-62MPG on arrival.
Stevejust,
My driving situation is vastly different than yours and I think you are doing good.
In my own situation I am still finding more bad habbits and techniques, shortcuts to improve performance and MPG together: Only recently took the HCH out for some MPG
performance tests.
Not sure if those will help but the tests were all ran on a slight incline on only a 1/2 mile strip of highway.
If you are really serious about improving your MPG numbers the next time you drive try to notice EVRERY thing you do while you are doing it and ask yourself if there is any way to conserve. Watch your instant FCD it will tell you how you are doing.
Read carefully the article
driving for efficiency which was written myself but the bulk of the more valuable lessons I recieved from Wayne. (Thanks). The only thing I would change there is accelerating technique given my testing data.
For Waynes question:
On a flat road, zero wind and at least 80's temp my HCH will sustain
50MPH at 84MPG (80 +1bar).
60MPH at about 64MPG
70MPH at about 54MPG.
80MPH at about 44 MPG
42-48MPH seems to be it's MPG "Sweet spot".
THanks