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Old 12-20-2012, 03:37 AM   #28 (permalink)
bwilson4web
Engineering first
 
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Join Date: Mar 2009
Location: Huntsville, AL
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17 i3-REx - '14 BMW i3-REx
Last 3: 45.67 mpg (US)

Blue Bob's - '19 Tesla Std Rng Plus
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Quote:
Originally Posted by RobertSmalls View Post
. . .
The car is programed to try to get its catalytic converter hot within a certain number of minutes of being turned on. . . .
The catalytic converter "light off" is about 45-55 seconds and common to our 2003 and 2010 Prius. One of the best metrics is MG1 torque but you can also see this by watching the mass-flow (or gallons per hour Scangauge II.) The catalytic warm-up phase is an "EV with engine idle" so my strategy is:
  • Mentally start a 45-50 second 'clock' to accelerate to a coasting speed.
  • Accelerate modestly, use your instruments to keep engine in 'idle' mode. I typically reach 35-40 mph when I am able to shift into "N".
  • Park near exit, this allows you to maximize acceleration in this brief phase.
I know 'common wisdom' is drawing on traction battery charge is expensive to replace. In my case, I'm finding the charge is replaced within 2-3 miles and at 45-55 mph, I can't find a significant hit. This is not in any way an endorsement of trying to maximize regeneration which is fuel inefficient. Rather this brief interval is available and can be exploited.

Bob Wilson
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2019 Tesla Model 3 Std. Range Plus - 215 mi EV
2017 BMW i3-REx - 106 mi EV, 88 mi mid-grade
Retired engineer, Huntsville, AL
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