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post #11 of 16 (permalink) Old 05-24-2006, 03:37 AM
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Originally Posted by hdrygas
Originally Posted by ken1784
We consume 1 or 2 cc of gasoline to start the engine when the vehicle is exceeding 42mph or shifting to B, then the game was over.
Ken that is very interesting. You are suggesting that on star up there is a brief period when the ICE starts before it shuts down. Please help me understand this. I have not seen this on the CAN View but it may be brief and difficult to see.
Yes, it is difficult to see the brief fuel injection.
My SuperMID M-1 mileage meter counts the fuel usage with 1 cc unit.
Also, my SuperMID T-1 tacho meter has an injector LED and it shows one or two seconds injection time to kick the engine.

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post #12 of 16 (permalink) Old 05-24-2006, 09:23 AM
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Getting back to Andrew's question...

I would vote for light pressure on the brake to keep your speed under 41 MPH. But I would vote no if the speed limit on your hill is 55 MPH. In that situation, I'd waste a few cc's of gas to keep my fellow drivers happy.

On my commute home, there is a series of small hills that if I put the car in neutral or press the gas enough to kill regen, the car would reach speeds over 50 MPH. However, the speed limit is 35 MPH, and since my daughter has been presented with a couple of speeding tickets lately, I feel I must set an example

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post #13 of 16 (permalink) Old 05-24-2006, 09:51 AM Thread Starter
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Thats kinda what I am doing. Only difference is I do not try to use eletric in excess. But down a long hill it would make sense to keep it under 41 and stay in eletric. In fact I do not use any eletric any way, I charge the battery. My battery goes up to green by the time i am half way down the mountian.

The speed limit is 30. Most people drive around 40-45. Keep in mind it is a rural road and goes over the mountian and through the woods... literally. Its kinda twisty windey but not so much that you have to have to drive real slow. There hardly is any traffic. Every now and then you see a car or 2 but its pretty much empty. The only people driving 55+ on the road are crazy teens with thier beefed up yellow trucks. The "Cool" kids! Most stay under 45. I do have to use a little more than light pressure to keep it under 41 mph because of the gade of the hill. Almost every one I follow down the hill uses the breaks more than lightly, but still some times go 45mph or so. I dont think keeping my speed under 40 or even down in the safe zone of 35 will really slow anyone up... if I even see any one on the way down.
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post #14 of 16 (permalink) Old 05-24-2006, 10:10 AM
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I've slept on it. It seems that keeping the engine from spinning most of the way, but letting it coast up to your maximum comfortable speed at the end of the hill so you can coast at the end, should give you the best efficiency. Using B gear rather than the brakes might also be a good idea.

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post #15 of 16 (permalink) Old 05-24-2006, 10:31 AM
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Long downhill runs always fill my battery, even with the cruise set for 65. Semantics over 'little gas' or 'no gas' don't matter a lot when the average MPGs keep going up. The last 8 miles south from Virginia into North Carolina on I-77 is always fun, although setting the cruise to 65 is important to keep moving fast enough to avoid being squashed by the big trucks...

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post #16 of 16 (permalink) Old 05-24-2006, 01:45 PM
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As Hep mentions, going down a steep 2 mile hill is an ideal situation for B mode. I use it all the time when going down a 3 mile steep hill. The engine spins higher in this mode than in drive, but IMO it's much better to use minimal fuel than to rely totally on brakes. Otherwise, you'll shorten brake life significantly if this is a regular route for you. Caveat: Once the battery is fully charged (8 green bars), the ICE will start spinning much higher in B in an effort to prevent overcharging. At this point, I personally take it out of B into D for the rest of the way down. This occurs at 1 mile in cold temp and 2-3 miles in warm temp.
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