Author Topic: Fuel Milage  (Read 1905 times)

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Offline chart1

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Fuel Milage
« on: January 24, 2011, 03:08:07 AM »
1976 MCI 8
8v71/740auto
8" roof raise

Offline Highway Yacht

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Re: Fuel Milage
« Reply #1 on: January 24, 2011, 07:54:46 AM »
Very interesting article... Thanks..
1979 MC-9
8V71T HT740
Locust, North Carolina

Offline Steve5B

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Re: Fuel Milage
« Reply #2 on: January 25, 2011, 01:03:36 PM »


   That's a good article, thanks!

   Steve 5B....

Offline Bevans

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Re: Fuel Milage
« Reply #3 on: January 25, 2011, 02:25:09 PM »
Here is an interesting chart

Brian
1980 MCI MC-5C
8V-71T military engine and Spicer 4 speed
Tatamagouche Nova Scotia

Offline Bevans

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Re: Fuel Milage
« Reply #4 on: January 25, 2011, 02:27:22 PM »
and...  Interesting for some, the torque of the N55 and N60  injector motors peaks at 1200 rpm, while the torque of the N65 engine, with advanced cam timing, peaks at 1600 rpm.  Yet if you peruse the torque curve from the earlier chart, you see that the actual torque of the N65 engine at 1200 rpm is still 780 ft-lbs or so - higher than either of the other two engines...  So you lose no low end torque with the bigger injectors and advanced timing, only gain across the curve.

Brian
« Last Edit: January 25, 2011, 02:39:44 PM by Bevans »
1980 MCI MC-5C
8V-71T military engine and Spicer 4 speed
Tatamagouche Nova Scotia

Offline Bevans

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Re: Fuel Milage
« Reply #5 on: January 25, 2011, 02:28:06 PM »
and
1980 MCI MC-5C
8V-71T military engine and Spicer 4 speed
Tatamagouche Nova Scotia

Offline Bevans

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Re: Fuel Milage
« Reply #6 on: January 25, 2011, 02:28:43 PM »
and - finally
1980 MCI MC-5C
8V-71T military engine and Spicer 4 speed
Tatamagouche Nova Scotia

Offline markmc7

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Re: Fuel Milage
« Reply #7 on: January 25, 2011, 02:51:39 PM »
This is all Great stuff. Thanks for posting it

Mark
my bus is named "one peace at a time"

Offline Highway Yacht

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Re: Fuel Milage
« Reply #8 on: January 25, 2011, 11:54:52 PM »
I wonder if that Military Spec sheet is for my motor also??? It was a surplus 1987 Military Tank engine.. I was told I have N90 injectors in mine but that hasn't been confirmed yet.
1979 MC-9
8V71T HT740
Locust, North Carolina

Offline Bevans

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Re: Fuel Milage
« Reply #9 on: January 27, 2011, 03:07:23 PM »
I wouldn't be surprised if it is.  The engine in the sheet has 90 injectors, and governed at 2500 rpm no-load speed!  My 8V71T industrial has N80 injectors, no idea what it's governor is set at.

Brian
1980 MCI MC-5C
8V-71T military engine and Spicer 4 speed
Tatamagouche Nova Scotia