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Old 03-15-2011, 01:35 PM   #36 (permalink)
t vago
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Quote:
Originally Posted by Joenavy85 View Post
light acceleration should be a given on this website (engine load should be kept as low as practical). RPM has little to do with when the TC locks, it's typically based on speed and engine load
Not entirely true.

Moderate or brisk acceleration actually saves more gas, compared to light acceleration. It is true that you might see higher instantaneous fuel consumption, but the engine isn't forced to both propel the vehicle forward and generate a decently high vacuum. In other words, brisk acceleration puts the engine closer to the ideal area on its BFSC map, than would light acceleration.



Quote:
In engines that use throttles, high pumping losses occur in part-throttle conditions. That is, the engine needs to do work in order to draw air past the partly closed throttle. One result of this is that as load decreases and the throttle is closed to a greater extent, Specific Fuel Consumption (ie the fuel consumed per power produced) becomes increasingly worse.

This graph shows the phenomenon. At 100 percent load (ie wide open throttle) this engine has a minimum Specific Fuel Consumption (SPC) of 0.43 – see the bottom curve. With the throttle open only 25 per cent, the minimum SPC has risen by 63 per cent, while at 2000 rpm, it has risen by a massive 117 per cent!
(link)

Just don't floor it to the point where the engine computer goes into open loop.
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