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What rpm do you like on the freeway

ShadowsPapa

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Difference in specified diameter of stock Overland vs. stock Rubicon Falken A/Ts is .6", barely over half an inch so revolutions difference per mile is minimal. (not quite 12)

Inches in a mile - 63360
101.15 circumference for Overland - rotations per mile = 626.4
103.04 circumference for Rubicon - rotations per mile = 614.9

Is my math right?
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Really not that much different than mine. In 8th at just over 2000 rpm running just at 80

mines a rubicon with 410 and BFG 37 ko2
 

KurtP

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I have tuned mine so ot stays in 6th until positive torque surpassed 15 percent of the shift into 7th speed. I run about 2600 RPM at 65 then ot drops to 2200, and stays in seventh unless I go over 40 percent throttle and 30 percent negative torque. It will flip into 8th on flat ground or down hill grades I tried to set it so ot would not shift back until 20 percent negative torque and 30 percent pedal, bit there is an override that kicks it back sooner that I dont have access to. My guess is a clutch torque limit issue. It runs about 1900 rpm in 8th at 65. With my 7th delay you do not even feel it shift. It just clicks over to the next gear and away you go
Is the transmission tuning/lock up schedule why the Gladiator makes less low end tq on the dyno compared to the wrangler?
 

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Is the transmission tuning/lock up schedule why the Gladiator makes less low end tq on the dyno compared to the wrangler?
Could be. They havethe converter working way morenin the Gladiator than the wrangler. Not sure why. I tried using the RAM shift schedule, and it worked ok but any agressive driving caused it to back shift quite a bit and abruptly. Wonder what the weight difference is between the wrangler and Gladiator
 

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Could be. They havethe converter working way morenin the Gladiator than the wrangler. Not sure why. I tried using the RAM shift schedule, and it worked ok but any agressive driving caused it to back shift quite a bit and abruptly. Wonder what the weight difference is between the wrangler and Gladiator
Not sure. My guess is theres more tq converter slip to smooth out lash from towing so The pussies at car and driver dont bitch. They should just let it go to lock up sooner. It costs us 20lbft at 2k compared to wrangler.
 

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@DAVECS1 given what the trans is doing, do you feel we can still access the mechanical advantage of the twin screw blower over a centrifugal? Those units arent even building the tq early enough to worry about this i dont think.
 

DAVECS1

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@DAVECS1 given what the trans is doing, do you feel we can still access the mechanical advantage of the twin screw blower over a centrifugal? Those units arent even building the tq early enough to worry about this i dont think.
You need to drive my tune. Not only does it feel good but listening to the low grade whistle as you accelerate from a stop. Makes it feel like a high dollar land rover or something.
 

Volt0

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Difference in specified diameter of stock Overland vs. stock Rubicon Falken A/Ts is .6", barely over half an inch so revolutions difference per mile is minimal. (not quite 12)

Inches in a mile - 63360
101.15 circumference for Overland - rotations per mile = 626.4
103.04 circumference for Rubicon - rotations per mile = 614.9

Is my math right?
you’re close for sure. The tire specs on the falcon a/t say 634 revs per mile. They aren’t true 33” tires, at 37psi ( per the door plate ) mine never measured above 32.5” or so. Math equations might need to account for the physics of the squish from the weight of the vehicle.
 

Volt0

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Does anyone have a reference to a chart that shows hp/torque for the 3.6?
 

redriderjf87

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A little more rpm on the 3.6 won't hurt anything in my view. Just part of having a v6 in a heavier, less aerodynamic vehicle.

I've found that having less rpm and bogging the motor down uses more gas than having some more rpm and some power on tap when you hit a hill or need to accelerate a little. When you don't need the extra power/rpm, you're giving less throttle, which minimizes the difference in extra gas you'd be using.

I prefer staying in 5th in my stock Willy's, which is about 2,200 rpm (or maybe a hair more) at 70 mph. Ideally I'd like even a little more rpm, but that's about the minimum to be able to cruise and not constantly downshift at the slightest incline.

Forgot to mention I have a manual for what it's worth.
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