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Old 11-02-2020, 09:59 AM   #49 (permalink)
Joggernot
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Quote:
Originally Posted by Michaelflat1 View Post
It's worth noting that automatics can have lower RPM DFCO entry points than a manual transmission.

On a manual, it might be 1500rpm entry, and 1250rpm exit.. This is because as you put the clutch down (when slowing) there has to be time for the injectors to come back on, stabilise airfuel ratio and produce a smooth idle.. Pushing the clutch down even at like 1400rpm whilst in DFCO you see the revs shoot down to 1150rpm or so, they raise by like 50rpm after (injectors come back) and then it smoothly drops to the idle speed.

CVT, the ECU doesn't have to be in a constant state of worry for a driver pushing the clutch pedal down.. Same with old school automatics... I remember seeing somewhere someone with a DFCO exit of 900rpm on their V8 4 speed auto truck.

+ a well tuned CVT could keep engine RPM right near the floor of DFCO to minimise frictional and pumping losses.
Not sure about this...I have a Honda CRV with CVT and a Scangage. When I lift from the throttle, I get a momentary DFCO (about 1 second), and then the CVT apparently "equalizes" and the DFCO goes off. No more DFCO. Just my experience.
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