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Old 07-08-2008, 10:37 PM   #17 (permalink)
Gregte
EcoModding Apprentice
 
Join Date: May 2008
Location: South Dakota
Posts: 117

GMC Sonoma - '94 GMC Sonoma
90 day: 36.97 mpg (US)
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Quote:
Originally Posted by jonr View Post
Gregte - what leads you to believe that very slow acceleration leads to better overall MPG?
Oh, I don't. All I was asking was in reference to two seemingly contrary ways to achieve better FE. One way is P&G the other way is slow accel and decel.

If slow acceleration is good for FE then it would seem that a slow accel followed by glide might be better than fast accel followed by glide (P&G).

I am definitely not arguing, just asking for clarification or explanation.

Also, I apologize for hijacking the thread. It was not my intent. I was not paying attention.

To get back on the subject of simple fuel economy devices, one that can be made quite easily, and in my opinion is very useful, is to feed the fuel injector signal to a voltmeter through a simple resistor/capacitor circuit. This allows you to monitor the voltmeter to see the relative amount of time the injectors are firing. You can learn when they are completely off (high speed deceleration) and when you are better to use a higher gear or lower gear, or when it is better to have engine off or left on regarding intended decel with engine braking.

If you have access to an o'scope to make yourself a chart/table you can then tell more precisely how much actual fuel you are burning per second per the reading on the voltmeter. This allows you to determine if voltage n1 at 55 MPH is a better or worse than voltage n2 at 65 MPH etc.

My only point I am trying to make is that it is not absolutely necessary to buy a scangage (although they are quite nice) to be able to actually know the amount of fuel you are using under varying conditions.

However, the accelerometer, as this thread is about, is likely going to be a much better general type of tool for many people to actually make good use of.
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