FJ-KILLER

I have a 2008 Unlimited with 3.73 gears they say 202hp and 240lbs. of torque at the crank so I figure 160hp and 180-90lbs. at the wheels?, plus is have a Gibson exhaust/ superchip/ Airaid CAI.

I am aware that in 4low you have twice as much torque compared to 2wd or 4wd but can anyone tell me exactly how much in 4low is it simply doubling the number in which case it would be around the high 300s or is there more math involved? Just curious.

Thanks!

ronjenx

On paper, it is that simple to get an approximate torque number. You have to remember the original numbers you quoted are at full throttle, and max rpm.
You would never do that in 4lo. You would have to look at a dyno graph and see what it's putting out at the rpm you would be at in 4lo, then do the math.

JKbender

The torque value gets multiplied by the change in gear ratio. In this case 2.73 for non-Rubi and 4.0 for a Rubi.

Power = Torque X 2(3.14) X Rotational Speed

Power is constant. Torque is multiplied by the gear ratio and rotational speed is divided by that same ratio to keep the system in balance.

FJ-KILLER

Cool, thanks guys!

Tooadvanced

Don't forget tranmission ratio as well as axle ratio. All multipliers

Freewill

Plus one more torque multiplier if you have a torque converter. The torque converter makes low gear lower than the lowest gear on a manual.