RPM's and milage?

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RPM's and milage?

Postby 93 W350 LE » Wed Oct 02, 2013 10:28 am

What rpm seems to get you the best milage with your automatics?
Do they seem to get better mpg's when you cruise above the stall speed, or lower in the range?

Thanks for any replies.

Eric
93 W350 LE Club cab dually automatic, Banks Power Pack w/ exhaust, Banks tach and pyrometer, Isspro boost gauge, GearVendors O.D., BD exhaust brake, Kelderman Compuride and front bags. My Dad was the 2nd owner.
So far; rotated fuel pin, bottomed star,1/2 turn on smoke screw.
Daily driver and occasional 14k lb 5th wheel hauler.
Thank a veteran for your freedoms!
93 W350 LE
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Re: RPM's and milage?

Postby RCCUMMINS89 » Wed Oct 02, 2013 11:38 am

Depends a lot on pump tuning and mods...........

HOWEVER, in a stock or close to stock truck with "small" injectors.......lower the better.

From everything I've been around with the above.........1650 seems to be pretty sweet.

Now, if you have a truck like mine (loads of timing, huge injectors) rpm doesn't really affect it that much. More or less strictly speed. (above 75 wind resistance and just straight hp takes to move my heavy butt takes over)
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Re: RPM's and milage?

Postby simplysmn » Sat Oct 05, 2013 8:47 pm

Well with my Crewcab 410's and 37's 366 spring fuel pin and a HX35 with a 16 housing,star wheel down some smoke screw in some , It loves to run about 1800 to 2000 rpm's and roughly 17 mpg maybe 18 .With the Pedal Burried on the floor it will run 2200 all day long at just a Hair over 100 mph :mrgreen:
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Re: RPM's and milage?

Postby 93 W350 LE » Mon Oct 07, 2013 7:03 am

I am hoping to be able to haul my 14k# 5th wheel, and be able to stay above 10mpg. Hoping...


Eric
93 W350 LE Club cab dually automatic, Banks Power Pack w/ exhaust, Banks tach and pyrometer, Isspro boost gauge, GearVendors O.D., BD exhaust brake, Kelderman Compuride and front bags. My Dad was the 2nd owner.
So far; rotated fuel pin, bottomed star,1/2 turn on smoke screw.
Daily driver and occasional 14k lb 5th wheel hauler.
Thank a veteran for your freedoms!
93 W350 LE
fuel screw!!!!
 
Posts: 106
Joined: Sun May 12, 2013 6:30 pm
Location: SWFlorida
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Re: RPM's and milage?

Postby simplysmn » Mon Oct 07, 2013 7:19 am

You shouldn't have any troubles doing that .
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Re: RPM's and milage?

Postby 1STGENFARMBOY » Mon Oct 07, 2013 8:46 pm

If you have 3.54 gears you can pull in 3rd at 55-60 and get 12-13, it won't change much in OD but your trans will build a lot of heat.

I would put in a trans temp gauge with the sensor in the pan, if'n I was you.

keep the temp under 200* and it will last lots longer.
93 W250 STD CAB, AUTO 3.55, GAUGES, 80HP DDP STICKS, DENNY T ,16CM HOUSING, 60MM GILLETT, VE MAXED,BHAF, BHFF, 366 SPRING,P/S INTERCOOLER, TIMS COOLER TUBS, TIMMING 1/8 BUMP,4in TURBO BACK TO DUEL 5IN STACKS,33 12.50 BFG, HOLLEY BLACK, CONVERTER COOMING.
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Re: RPM's and milage?

Postby 93 W350 LE » Tue Oct 08, 2013 3:32 pm

Sometimes wish I had 3.54's. 4.10's with 235/80 16's spins some rms. Trans temp gauge and aux cooler I think will give me more peace of mind. Looks like this will be a long 60mph trip.

Eric
93 W350 LE Club cab dually automatic, Banks Power Pack w/ exhaust, Banks tach and pyrometer, Isspro boost gauge, GearVendors O.D., BD exhaust brake, Kelderman Compuride and front bags. My Dad was the 2nd owner.
So far; rotated fuel pin, bottomed star,1/2 turn on smoke screw.
Daily driver and occasional 14k lb 5th wheel hauler.
Thank a veteran for your freedoms!
93 W350 LE
fuel screw!!!!
 
Posts: 106
Joined: Sun May 12, 2013 6:30 pm
Location: SWFlorida
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Re: RPM's and milage?

Postby BILTIT » Tue Oct 08, 2013 3:35 pm

Get taller tires if you can fit them.
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Re: RPM's and milage?

Postby 93 W350 LE » Tue Oct 08, 2013 3:44 pm

BILTIT wrote:Get taller tires if you can fit them.

That has crossed my mind, but just put four new ones on this year.

Eric
93 W350 LE Club cab dually automatic, Banks Power Pack w/ exhaust, Banks tach and pyrometer, Isspro boost gauge, GearVendors O.D., BD exhaust brake, Kelderman Compuride and front bags. My Dad was the 2nd owner.
So far; rotated fuel pin, bottomed star,1/2 turn on smoke screw.
Daily driver and occasional 14k lb 5th wheel hauler.
Thank a veteran for your freedoms!
93 W350 LE
fuel screw!!!!
 
Posts: 106
Joined: Sun May 12, 2013 6:30 pm
Location: SWFlorida
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