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Old 11-11-2012, 05:58 PM   #20
ill86
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Quote:
Originally Posted by topazsparrow View Post
how does a lack of low - mid range torque increase driveability???

It's always been my understanding that the torque dip was a byproduct of the dual fuel injector setup. It's optimized for low rpm torque and fuel economy via the Port injection, then switches over to direct injection to get the power in the high RPM's where it can more accurately introduce fuel.

The torque dip isn't intentional, but it's accepted as a byproduct of the engines "dual power band" characteristic. As shown in above graphs, you can tune it out to an extent, but at what cost? Fuel savings?
You are incorrect in thinking it is not intentional. The response I have given is from the "horse's mouth". Fuel economy and driveability is why it is there.

When driving on a race track if shifting at or near redline you will not fall in this "dip" on the next upshift.

Around town it is desirable to shift before the torque "dip" to maintain decent low end torque and fuel economy.

I have not encountered any situation where the "dip" has caused me grief. On the street or on track. YMMV.

Peace.
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