Gear Vendors with 3:54 rear end
11-18-2010, 05:01 AM
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Gear Vendors with 3:54 rear end
i get 25MPG consistently and i was wondering if i would see a big improvement in milage with a gear vendors or is over 25 hard to ask for. thanks.
11-18-2010, 06:14 AM
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25mpg is unreal I don't see how you're going to get better mileage than that.
The gear vendors on top of the 23% overdrive with 3.54 ring gear will mean you'll have to be going fasssst to be in the MPG range of a cummins.
How fast do you run to get this 25 mpg?
The gear vendors on top of the 23% overdrive with 3.54 ring gear will mean you'll have to be going fasssst to be in the MPG range of a cummins.
How fast do you run to get this 25 mpg?
11-18-2010, 11:13 AM
#5
It would be tough to get better than that, but still possible. You're starting to fight the aerodynamic and weight limitations of the vehicle. I get 24mpg at 65mph with a GV, 727 transmission, and 3.07 rear gears. I'm hoping for over 30 once I switch to a lockup converter 46RH and add 10 deg. of timing.
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11-18-2010, 06:40 PM
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Nope If I didnt see it first hand I would be a skeptic. but my father in law had a 92 12v and would get 25 all the time on the hwy there are some that get great mpg .the best i can get with my 90 IS 19 my 01 gets 24+ with the wife driving it, I can only seem to get 20-21 and all were hand calced
11-18-2010, 08:04 PM
#11
I got 25MPG hand calculated with my '89 that had a getrag 5 speed and 3.07 gears. Not sure about the GV...
11-18-2010, 11:25 PM
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Let's do some figuring.
If your best mileage is at 62 mph (100 kph), you are turning about 1875 rpm with a 235/85/16 or 265/75/16 tire. Overall gear ratio in overdrive with a Getrag and 3.54s equals a 2.72 final drive.
With a gear vendors your final drive ratio would now be 2.13 making 1875 rpm equate to 80 mph (129 kph) and 100 kph would equal 1455 rpm.
Some guys have combined the 3.07 axles with Getrags and that brings the final drive down to 2.36 which is still lower geared than the combo your considering.
The question is how many rpm can you turn yet still maintain speed without lugging?
If you plan to keep the HX35 you will be ok. If you go to a larger turbo you may not.
If your best mileage is at 62 mph (100 kph), you are turning about 1875 rpm with a 235/85/16 or 265/75/16 tire. Overall gear ratio in overdrive with a Getrag and 3.54s equals a 2.72 final drive.
With a gear vendors your final drive ratio would now be 2.13 making 1875 rpm equate to 80 mph (129 kph) and 100 kph would equal 1455 rpm.
Some guys have combined the 3.07 axles with Getrags and that brings the final drive down to 2.36 which is still lower geared than the combo your considering.
The question is how many rpm can you turn yet still maintain speed without lugging?
If you plan to keep the HX35 you will be ok. If you go to a larger turbo you may not.
11-19-2010, 06:18 AM
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rbrettctd said a while ago with his getrag/3.07 combo he has to be running like 80 to get good mileage, any thing lower than that he's lugging and mileage is suffering
11-19-2010, 10:20 AM
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Assuming your odometer is accurately accruing mileage, right? Whenever I read of a person claiming notable deviations from the norm, I have to question the data.
11-19-2010, 10:33 AM
#15
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I'm close to 25mi/gal(Imp) empty and averaged 17mpg pulling my current 5th wheel camper trailer across Canada. On that trip I ran in the 55-60 mph range, so comparisons would have to take that into account. I rarely drive my age (65), ... 