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Old 08-23-2010, 02:49 PM   #12 (permalink)
some_other_dave
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Quote:
Originally Posted by sevenspeed View Post
As for the all things being equal does that include horespower? Like can a v-tec motor get more or equal mileage in the same car then a non-vtec if driven the same? And the new motors are 1.7L with v-tec but forgot the horespower rating.
HP: Yes and no. In general, engines that are capable of making lots and lots of power are less optimal at the lower RPMs that we prefer. But the VTEC system can negate that to some extent, because there are two cam profiles to select from. One can be optimized for higher RPM operation and higher power, while one can be optimized for lower RPM.

VTEC can be set up so that the engine can go into an Atkinson-like cycle (lots of reading out there on that!) which can help cruise fuel economy.

In general, I would guess that the D17 would give you the best fuel economy of the three engines you have listed. Particularly if you use a gearbox with nice tall gears. Note that this is all guessing. We don't have systematic testing of those drivetrains in a single chassis, so we're just speculating.

-soD
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