New wheels - PaleMelanesian's 2009 Fit

Discussion in 'My Ride' started by PaleMelanesian, Jan 14, 2013.

  1. RedylC94

    RedylC94 Well-Known Member

    One could take a short-cut to that data point by simply dividing miles per hour by gallons per hour (assuming instrumentation that shows gph).

    Additional arithmetic reveals the fuel burned per engine revolution at the lowest speed in 2nd was barely more than at idle. That's reasonable, since the engine was very lightly loaded.
     
    Last edited: Jul 4, 2013
  2. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    For an instant reading, yes you could. However, that fluctuates so much it's nearly useless unless you average it over some distance.
     
  3. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    I fixed my headrests.

    Like most new cars, they were too far forward. Thanks to new crash tests, they have to be to get a good score. It hurts my neck by forcing me to hunch forward all the time.

    I put them in a bench vise upside down, slipped a pipe over the post, and bent it back about 15 degrees. Now it's almost perfect. The posts bend forward right below the cushion, and I just straightened the bend a bit.

    Not my car, but it shows the pushed-forward position before I changed mine.
    [​IMG]
     
    Last edited: Aug 22, 2013
  4. EdwinTheMagnificent

    EdwinTheMagnificent Legend In His Mind

    Andrew , does that pic show the "before" or the "after" ?
     
  5. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    Sorry. That's a google-searched "before" shot.

    Here's a comparison between that and my car after. Picture taken with a potato-cam, apparently.
    [​IMG][​IMG]
     
  6. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    [​IMG]
    Perspective makes the car look bigger. In reality the difference is even more dramatic!

    One of these has hauled, this week:
    • Hay bales
    • Feed sacks
    • a 300-ft roll of field fencing (160 lb)
    • fence posts

    ... and it's not the dark one. :p
     
  7. RedylC94

    RedylC94 Well-Known Member

    It looks like the driver of "the dark one" hasn't learned how to park properly.
     
  8. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    There was no way it could fit in the spot. He missed by about a foot on the front, but that would still leave the back wheels on the line.

    I think it was dark navy blue, but don't exactly remember.
     
  9. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    I'm not sure the LOD reading is the most useful in this car, with its electronic throttle wizardry. I've been using ~80 LOD for my pulses, which is fairly slow. I pulled up the TPS and LOOP gauges for some extra testing.

    TPS idle: 17 cold / 14 hot
    TPS max: 77
    TPS at 80 LOD: 25 or so.

    I'm trying some heavier pulses. I've found that it holds Closed Loop at least up to 70 TPS, which is much higher than the 25 i've been using. Basically anything short of "on the floor" is closed loop. The jury's still out on what's more efficient, but it certainly is faster. The trick is to use heavier throttle, but not combine it with higher speed. That would be a losing proposition for sure.
     
  10. RedylC94

    RedylC94 Well-Known Member

    Do you know the manifold pressure (MAP) or vacuum in those conditions? Wouldn't TPS have to increase with increasing speed in order to maintain constant MAP (or torque)?

    Thanx!
     
  11. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    Not enough gauges to monitor everything! :D In the past I've noticed that MAP and LOD are directly related, though. ~13 psi MAP is roughly 80 LOD.

    The things is that Honda's recent models have electronic throttle and valve timing and they use some magic in there instead of a direct pedal-to-throttle mapping. At low load cruising it actually opens the throttle more, and uses a delayed intake valve closing to push some intake charge back out before compressing. Open throttle for lower pumping loss, but still lower power because there's less fuel-air to burn in the cylinder.
     
  12. Die2self

    Die2self Saving more by using less!

    do you need me to do any testing for you Andrew to compare with what you get?
     
  13. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    I'm not sure any of your results would be comparable to mine, but I'd welcome any more data. I found you can give it a LOT more throttle than I thought an still be Closed Loop. Makes the drive more fun. :D It's hard to compare results with the weather fluctuating, though.
     
  14. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    It looks promising. On my one 1/2 mile steady climb near the end of the trip I only lost 4 mpg instead of the usual 6-8. Definitely need more data but I can at least say it's not a big loss.
     
  15. RedylC94

    RedylC94 Well-Known Member

    That makes sense. The engine should be more efficient with the heavier load, as long as it's not so heavy the mixture veers rich. We know you don't waste much during your "glide" phases.
     
  16. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    Thing is, I thought I was giving it heavy load. I'm only now, a year later, realizing how light I was on the pedal.
     
  17. Die2self

    Die2self Saving more by using less!

    should I be shooting for a 90 LOD number then. Usually my pulses are from 90-80. Have have some pause on 75 but it just seems really slow to me. The typical pulse if around 85. I am interested to see if I need to switch to a different gauge than LOD to be more accurate toward the 75-80% actual load on the engine.
     
  18. PaleMelanesian

    PaleMelanesian Beat the System Staff Member

    I'm finding that LOD jumps all around the place. At light throttle it's predictable but once you get to 90 or so it's not directly connected to the pedal. My old standard 80 LOD comes to about 25 TPS, out of the 14-77 range. I'm trying 50 LOD now, and liking it. Still too soon to know for sure.
     
  19. Die2self

    Die2self Saving more by using less!

    I noticed that as well. It depends on your speed how the LOD numbers fall.

    When in town I try and pulse at 70 LOD numbers (which is pretty quick in 2-3-4 gear). For pulsing on the highway that LOD number at 45-50 MPH takes foreeeeeeevvvvvvveeeeeerrrrrrr to get to 55 MPH. So I usually shoot for 80-85 LOD reading, which is brisk but not overly so. anything above 90 LOD at 55 MPH doesn't give you any more quickness to your upper delta only wastes more gas.
     
  20. RedylC94

    RedylC94 Well-Known Member

    MAP is an actual measurement. I assume "LOD" is an estimate, based primarily on MAP. Does that estimate take into account things like each model's version of variable valve timing? If not, I don't see how it could be very accurate, especially at light loads.
     

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