santa gave me the pink slip to the jeep!

[Baja_XJ]

For 33s Id say 4:10s, just my .02, Im sure someone has an opposing opinion, I ran 33s with 4:88s for almost a year but it was way to low geared. Going 60 I was turning 3000 RPM, noway you would want to do that very long through the dez with a stock I6. With 4:10s you should have plenty of power to keep the tires turnin over whoops and what not and still be able to carry a good speed at a decent RPM. May want 4:56s though if you play in soft silty type stuff or sand

 

[DirtBound]

then 4.10's it will probably be. haha.
not to much sitly stuff where i run but definately some whoops. :] i like whoops. :]

 

[Loose_Nuts_Enterprises]

I would opt for the lower gears. Most of the guys that race are using 5.38 to 6.20. Lower gears are easier on the motor than taller ones since it's not lugging all the time. In our Jeepspeed car, we're running 5.86 and can still get 100 mph.

 

[Baja_XJ]

Jesus! Whats it rev at? Mines got the 35s and 4:88s and at 95 its 4k. I always gear for the torque band. I couldnt imagine running 5.86s, probably wouldnt want those in a DD... I know the I6 is a stout motor but I never thought it would deal with that many RPM that long

 

[Loose_Nuts_Enterprises]

It's around 5000 RPM in 5th gear. Average race speeds are 35-40 mph, so you want to be low geared enough to have good power there. We're using an AX-15 and 4th gear is the strongest gear, with the least drag. Those 5.86's give us enough power band to pull 3rd and 4th down low. We had 6.20's for a while, and it was awesome....but we topped out around 84mph, and the RPMs of the front driveshaft led to catastrophic failure a couple times... It did not like turning 25,000 RPMs (5000x0.79x6.20) Not enough top end for the long stretches, so the 5.86's seem to be a good compromise.

You're probably getting a little converter slippage pushing that fast with an auto, adding some to your RPMs.

 

[silverslk]

Let's see if Cal responds to this thread. He believes 32's and 4.88's are a great combination.

 

[cal]

I believe 32's and 4.56 are a great combination; but in this arena Dan (loose_nuts) has the best advice that can be given. He has been racing jeepspeed very successfully for a good while now, and knew what he was talking about before he started doing that.

But yeah, gear lower, not higher. The 4.0 doesn't really want to do any work under 2700 RPM's or so, and seems pretty content to sit at 4,000 for a long time. Goatman ran King of the Hammers 2009 pushing ~4,400 RPM's in second gear for upwards of 90 miles on his stroker with no problems.. with 5.13 gears and 40" tires, the stroker doesn't have enough power to pull 3rd on the whoops.

 

[DirtBound]

I believe 32's and 4.56 are a great combination; but in this arena Dan (loose_nuts) has the best advice that can be given. He has been racing jeepspeed very successfully for a good while now, and knew what he was talking about before he started doing that.

But yeah, gear lower, not higher. The 4.0 doesn't really want to do any work under 2700 RPM's or so, and seems pretty content to sit at 4,000 for a long time. Goatman ran King of the Hammers 2009 pushing ~4,400 RPM's in second gear for upwards of 90 miles on his stroker with no problems.. with 5.13 gears and 40" tires, the stroker doesn't have enough power to pull 3rd on the whoops.

thanks for all the feed back dudes. i guess i should have specified that it would be my DD and weekend prerunner though. not looking for racing gears. but still, thanks for all your .02 .

 

[silverslk]

Cal's advice still stands for a DD. I wouldn't go 4.10's. Go at least 4.56's and you should see better mileage not lugging the motor.

 

[Baja_XJ]

I could see 4:88s and 32s. But 31s if you do alot of highway driving Id say 4:56. I forgot to add mines 5speed so if the gear Im in is to high I just go down one, kinda hard to stay in one gear in a auto, Most my prerunning with the 35s and 4:88s I use 3rd gear and keep it around 65-80 turning about 4250-4750.

 

[xcm]

im a very happy camper w/ a "DD and weekend prerunner" running 4.56 on 33's.
it's high in the rev's, but i can go up uphill passes during the day without being passed once. i do 90 regularly, love it.

you cant split it perfectly 50/50, you gotta deal w/ some compromises for the offroad gains. if you want a kickass prerunner, 4.10's are the puss approach.

as far as MT/AT, ive got 3 jeeps in the family w/ 4.56/33x12.5/33x10.5/even 31x10.5, both varietys, and everyones happy.

 

[silverslk]

you cant split it perfectly 50/50, you gotta deal w/ some compromises for the offroad gains. if you want a kickass prerunner, 4.10's are the puss approach.

x2

It's like people who want a cage but don't want it in the way. If it's a pain in the ass and always in the way.....it's a safe cage.