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Don Y[_3_] Don Y[_3_] is offline
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Default OT. GM fuel mileage overstated

On 5/17/2016 6:05 AM, Frank wrote:
New cars play games shutting down cylinders when the power isn't
required.


Doubt this is happening on the Subaru.
I don't know how they can instantaneously measure mileage and would think it
extremely hard to do it on fuel usage.
Car also has a CVT which gives maybe an extra mpg.


Mileage is a takeoff on the tranny -- count wheel rotations per unit time
(or, at very low speeds, time per wheel rotation); ditto driveshaft, etc.

Fuel usage is by monitoring how *they* fire the injectors. You know how
much fuel is introduced with each activation (if it wasn't predictable,
the engine wouldn't run smoothly).

https://en.wikipedia.org/wiki/Variable_Cylinder_Management
https://en.wikipedia.org/wiki/Active_Fuel_Management
https://en.wikipedia.org/wiki/Multi-Displacement_System

It will be interesting to see how their CVT holds up over time!

We liked the two Subarus we test drove. But, the "tranny hump"
(where the bell housing would be on a rear-wheel drive vehicle)
was too wide and encroached on the leg position for the passenger
(your left foot can't be placed directly in front of your left *hip*,
let alone to the *left* of it!)