don't kill (shut off) your motor - a debate!

[8307c4]

There is a penalty for starting the engine yes, for non-hybrids if I don't foresee 20+ seconds I don't bother, this helps make up for the times I miscalculate.

But help it does, considerably, always.

[trebuchet03]

On "the other forum" I believe the number tested with a sound card O-scope was something like 6 seconds. And that was attributed to the engine acceleration over idle.

This figure goes down if you use that energy stored in your "spun up" engine. So if you're engaging the clutch before the engine falls back down to idle - that 6 second figure goes down.

I'll stand by skewbe's testing methods - unless someone brings empirical data to the table. Anything less is speculation.

In any case - a good hypermiler has the engine cut before reaching the stop light for that little extra something

[roflwaffle]

Originally Posted by trebuchet03

I'll stand by skewbe's testing methods - unless someone brings empirical data to the table. Anything less is speculation.

I think we can establish bounds and go from there w/o any testing via injector size and cranking time until startup. Those little things can only put out so much fuel for so much time. Compare that to idle consumption and we have the worst case idle time savings stuff and things.