Throttle Position During Acceleration and its effect on FE

[LxMike]

Originally Posted by rh77

Yup. I get it up to speed, and practice the usual driving techniques where the real FE lives at cruise. As you know, the automatic makes it tough with the kickdown at optimum throttle input.

(Redline is 6750 or thereabouts). So in first gear sometimes I shift from 1st to 2nd which holds the gear. I can give it 50-60% throttle from there on and shift into 3rd. Then the tricky part: getting it to stay in 3rd and give a dose of throttle; then at 3000 I lift and left the car shift until 4th gear.

If you ask a 100 hypermilers you'll get different answers: accelerate as slow as possible, or get to the point and start to build the FE. I'm not saying to floor-it as that would cause open loop, but try to get up to 3-grand to see if it works out.

Strangely enough, if you take the same car and conditions:

Accelerate slowly: the Scangauge will show an avg of 17 mpg for say 1 minute. Then at minute 2, you're into 40 mpg territory.

Accelerate briskly: the scanguage will show 9 mpg for 0.5 minutes. Then at 30 seconds, you're at 40 mpg at each interval up to 2 minutes. Average FE over 2 minutes in each scenario:

Math:

Slow Accel: ((17+40)/2 = 28.5 mpg avg. at minute 2
Fast Accel: (9+60)/2 = 34.5 mpg avg. at minute 2 (60 is 1.5*40 for the 90 seconds of 40 mpg).

As you can see, it's worth getting up to speed instead of spending a lot of time at ineffecient acceleration. It works for me in the TSX and in the 'Teg. I'd say that I'm doing the best I can now with both cars (TSX still breaking in and we keep getting better mileage at each tank -- the 'Teg is up to Hypermiler due to a recent stent on the long Interstates of Oklahoma and Kansas. The mirrors were folding in for less Cd. and I ended up in the 40's at cruise with constant throttle on hills.

RH77

Thats something i've been wondering with having an automatic and having it doing the shifting. i'm real easy on the pedal and s.g shows max rpm's never go more than 2300. i'm wondering about getting up to speed a bit quicker?? my cars auto tranny the t.c will lock up at 42 mph. when it does rpm's drop 300-400 and mileage jumps from low 30's to consistent mid 40's and nearly 50 at times. I think this is my next mileage exp to work on.