coasting

[krousdb]

Originally Posted by MetroMPG

since running this test, of course i've been shutting off the engine more for coasting than i used to.

my segment mileage, according to the scangauge, has shot way up. example:

68.1 mpg (US) over 30.5 km of sub/exurban driving (23 mph avg speed / 42 mph max; rain, wet roads; 6 C / 46 F ambient; 1.25 hrs EBH.)

this trip was actually above the 70 MPG level on the way back to the house, and then i got hit by 3 red lights in a row and a train crossing at the bottom of my best hill, and these things dragged it down to 68.1

i suspect that through using engine-off coasting more i'm going to see the "hybrid FE flip flop": where my non-highway driving FE is going to exceed my highway-only numbers.

Looks like you will back on top of the gassavers gaslog standings in no time. I will have to work hard just to get past basjoos. And then you will be leapfrogging both of us.

I am going out today to get a new hacksaw blade. Which cylinder should I cut out, 2 or 3? Hmm. I will need a welder also I guess.

[MetroMPG]

Originally Posted by krousdb

Looks like you will back on top of the gassavers gaslog standings in no time. I will have to work hard just to get past basjoos. And then you will be leapfrogging both of us.

we'll see. my driving habits are about 70/30 highway/non-hwy, so won't get to use this technique as much.

i've still got to figure out ways to improve my highway (50 mph+) mpg.

btw: i would go for #2 and #4.

[JanGeo]

Actually take the one on the end and then you have to twist the crank for the 120 degree offset per rod journal. Funny was in a junk yard last year looking down the headless block of a Geo and saw just how short the bore really was and small . . . it's TINY!!

[MetroMPG]

Just need to workout the connection to the wheel thing.

what about an electric drive wheel that engages against one of your rear tires for low speed driving? you've got room in the back to make mechanism that would raise or lower the wheel a few inches. of course, you'd have to cut an access hole through the wheel arch...

[JanGeo]

Was actually thinking of using a 5th wheel that could be raised and lowered that would simplify the gearing. Problem with rubbing against the car tire is tread wear and contact patch plus the travel on a bumpy road is brutal. The Fifth wheel could be suspended properly and could be lifted over bumps and have limited down travel to prevent pot hole damage. Plus it would not interfere with normal vehicle operation and safety issues. Going to take a lever with a throttle grip to operate the 5th wheel . . . hummmm . . . separate digital speedo to record usage and to allow sycronization of ground and wheel speed . . . hummm . . . gear up . . . gear down . . . hummm.

[MetroMPG]

why not just a pusher trailer?

[JanGeo]

No hitch for trailing and safety issue when backing up as well as bridge tolls increase for another axle. Not to mention lack of control wires in the same vehicle and registration extra . . . need I say more? Guys do that on a bicycle to get around the powered vehicle laws.

All I need to make it work is a motor on a mount with a swing arm to the wheel and a belt drive and a lever to lower and raise the wheel. All wiring is on the chassis without anything moving other than the swingarm on cable or spring tension to the ground. Actually the drive angle can provide down force for traction and make it slip if braking action gets to great.

[rh77]

Originally Posted by MetroMPG

No engine-off stops at all? i don't mind using the starter once in a while, even in the manual shift car. 13 times in 9.7 km would be excessive, but i don't think 3 is. (it would have been 2 key starts, but i botched one of the clutch starts when i used my kill switch improperly.)

If I go to the ATM, then I shut down and coast to the machine, and when I go to the local coffee shop, I park instead of using the drive-thru. Subtle changes. But at lights, (city driving) which is 20% of my driving, the shut-down/re-start raises the RPM to a higher level of approx. 1500 RPMs intitially. If I shift immediately, the excessive revs create a hard engagement. If I wait the second to get the engine back to around 800-1000 RPM, then I get honked at. The neutral shift is faster and is easier on the aging tranny.

What I really need to do to get my mileage up is to improve the Cd. Nearly 80-90% of my driving is around 55-60 MPH. The techniques mentioned earlier are nearly to identical to those of a hybrid, which I've calculated to not be a benefit to my driving (other than the tax credit). Since joining gassavers.org, I've reduced my speed on the highway from 75-80 mph down to 57 mph. My gaslog shows a steady, but slight increase in my average FE. I continue to use the HAI, because the fuel trim is consistently lower, and more throttle is required to perform the same tasks (which has been proven to up the FE because of the increase in air pumped with no increase in RPM).

I don't know what to do next. If I invest in a ScanGuage, I can see in real-time what seems to be working. Maybe aero changes or lowering could help. I'd hate to have hit the proverbial "wall" with this car, as I've resolved to drive it until it becomes more costly to maintain than drive, then maybe it'll re-incarnate into a Rally car (don't tell my fam ;-) ). I feel as if I've summed up my entire feelings about my situation in one post, but progress has been minimal over the last few months since I've joined this site. I refuse to give up just because I have a short-geared final drive automatic connected to a moderately-high horsepower "LS" engine. Maybe when the automatics forum opens, some more brainstorming can occur, but probably 90% or more of members here have manuals, so how much input can we generate? I'm just frustrated -- I came back from the Auto Show this weekend just sickened of the average fuel economy of the vehicles out on the floor. Of course, I could get a different car but that isn't an option right now. The challenge lies in bettering what I have. OK, I'm done now. Thanks, sorry, good night and good luck.

RH77

[JanGeo]

the bigger the engine the better the improvement - try some friction reducing oil additives - believe me they WORK!

[MetroMPG]

did a little errand run today and man, the engine-off coasting continues to be awesome:

57.4 mpg (US) on a 15 km round-trip, from a cold start (5 C ambient), in city driving, where literally 9 out of the 10 traffic lights on my route was red.

i'm probably overdoing the engine-off business at this point, and still botching the occasional clutch start, mainly from waiting too long - e.g. road speed too slow to start in 5th. i need to figure out the range of speeds at which 5th, 4th or 3rd would be most appropriate for a clutch start.