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Old 04-12-2008, 07:53 AM   #13 (permalink)
Harpo
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Join Date: Mar 2008
Location: Gainesville, FL
Posts: 79

Harpo's Honda - '05 Honda Civic VP
90 day: 42.64 mpg (US)
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Load and RPM dependent

Quote:
Originally Posted by boxchain View Post
Thanks for the info Harpo. What's your rpm at DFCO trigger?

Coming down from a bridge (since we don't have hills )
As Elixer mentions, there are some hard factors like RPM. Anything above 35mph in OD seems to get DFCO to trigger. Below 35mph on OD DFCO does not trigger, implying the rpms are below the threshold. In the same scenario, with trans in 3rd, you can get lower DFCO mph, due to higher rpm, but glide is affected.

The manual says flat towing at ~35mph. Therefore, I won't go into neutral above 35mph. I've built several RWD tranmissions in my day, and some do not oil well without engine ouput and should not be flat towed at all. I try to get 'er in to N right at 35mph before DFCO releases resulting in a .05-.08gph reduction of fuel flow and longer glide if required. Timing with traffic is essential. Jumping back-forth to N in some traffic just isn't worth it to me.

I accept DFCO in OD on the long grade downhills where I can maintain 50mph+. Sure, I'd like to coast a bit farther, but no fuel flow and four 9's is where it's at! If it's rolling and I know I need energy to maintain speed without undue excessive load condition, I'll roll in 0.5gpm toward the bottom and accept a 10mph gain so I can sacrifice it at the top.

H.P. Long has a good grade! I grew up around your parts. I last lived on West End BLVD. Flood Town USA.
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