| LOST JEEPS http://www.lostjeeps.com/forum/phpBB3/ |
|
| Axle ratio question http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=1&t=25274 |
Page 1 of 1 |
| Author: | rlanda [ Wed Oct 10, 2007 5:31 pm ] |
| Post subject: | Axle ratio question |
I barely know what does "axle ratio" means, but I can't figure out why is it important. Could you tell the convenience of this number being smaller or larger and why? |
|
| Author: | Jeger [ Wed Oct 10, 2007 5:40 pm ] |
| Post subject: | |
Lets say your axle ratio is 3.73. That means that the driveshaft would have to turn 3.73 revolutions to get your wheels to turn 1 revolution. 4.10 gears means 4.10 turns from driveshaft to turn wheels once. So if nothing else changes a higher number axle ratio will make your engine turn faster at a given speed than lower number would. Going to a numerically higher gear ratio can help to correct for larger size tires, and it can enable to go slower for obstacles that require some finesse. |
|
| Author: | tjkj2002 [ Wed Oct 10, 2007 5:50 pm ] |
| Post subject: | Re: Axle ratio question |
rlanda wrote: I barely know what does "axle ratio" means, but I can't figure out why is it important. The gear ratio for the front and rear diffs(normally on a KJ) are 3.73:1,that means it take 3.73 turns of the drive shaft to make the wheels turn one full rotation,also it multiplies the turque coming from the driveshaft 3.73 times.Now gears are called low or high,low gears are numarically higher,4.10's are lower then 3.73's,and high gears are numarically lower,3.55's are higher gear ratio then 3.73's.The lower the gear ratio the more torque multiplication there is,but at the cost of high end power,say you have 3.73's and can do 130mph(it may take awhile to get there),well if you put in 4.56's you'll accelerate faster but may only get to 120mph.Higher ratio's = better MPG's(to a point) and lower ratio's are more for pulling and rock crawling.When adding bigger tires you need to put lower gears in to get back into the factory powerband,say you had 29" tires with 3.73 gears and went to 32" tires you would need 4.30 gears to be back in the factory powerband.
Could you tell the convenience of this number being smaller or larger and why? This chart may help with the rpms vs tire diameter-----http://www.4lo.com/calc/geartable.htm |
|
| Author: | tommudd [ Wed Oct 10, 2007 5:56 pm ] |
| Post subject: | Re: Axle ratio question |
tjkj2002 wrote: rlanda wrote: I barely know what does "axle ratio" means, but I can't figure out why is it important. The gear ratio for the front and rear diffs(normally on a KJ) are 3.73:1,that means it take 3.73 turns of the drive shaft to make the wheels turn one full rotation,also it multiplies the turque coming from the driveshaft 3.73 times.Now gears are called low or high,low gears are numarically higher,4.10's are lower then 3.73's,and high gears are numarically lower,3.55's are higher gear ratio then 3.73's.The lower the gear ratio the more torque multiplication there is,but at the cost of high end power,say you have 3.73's and can do 130mph(it may take awhile to get there),well if you put in 4.56's you'll accelerate faster but may only get to 120mph.Higher ratio's = better MPG's(to a point) and lower ratio's are more for pulling and rock crawling.When adding bigger tires you need to put lower gears in to get back into the factory powerband,say you had 29" tires with 3.73 gears and went to 32" tires you would need 4.30 gears to be back in the factory powerband.Could you tell the convenience of this number being smaller or larger and why? This chart may help with the rpms vs tire diameter-----http://www.4lo.com/calc/geartable.htm beat me to it so I just deleted mine! Great explanation! |
|
| Page 1 of 1 | All times are UTC - 5 hours [ DST ] |
| Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group http://www.phpbb.com/ |
|